BIOACTIVE POLYPEPTIDES FOR IMPROVEMENTS IN PLANT PROTECTION, GROWTH AND PRODUCTIVITY
Bioactive priming polypeptides are provided that are useful when applied to plants in agricultural formulations. Methods of using the formulations containing the bioactive priming polypeptides are also provided which are applied exogenously to the surface of a plant or a plant cell membrane or endogenously to the interior of a plant or to a plant cell. The bioactive priming polypeptides when applied to a plant, a plant part, or a plant growth medium or a rhizosphere in an area surrounding the plant or the plant part increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture.
This application is a divisional of U.S. application Ser. No. 17/350,746, filed on Jun. 17, 2021, which is a divisional of U.S. application Ser. No. 16/929,422, filed on Jul. 15, 2020, which is a divisional of U.S. application Ser. No. 16/041,059, filed on Jul. 20, 2018, issued as U.S. Pat. No. 10,717,767 on Jul. 21, 2020, which claims the benefit of U.S. Provisional Application No. 62/534,710, filed on Jul. 20, 2017. Each of the above-cited applications is incorporated herein by reference in its entirety.
FIELD OF THE INVENTIONBioactive priming polypeptides are provided which can be delivered in agricultural formulations. The polypeptides can be applied to crops to achieve agronomically desirable outcomes such as enhanced phenotypes in plants (e.g., those that exhibit protection against pest, disease agents and abiotic stress), increased plant growth, productivity and yield.
BACKGROUND OF THE INVENTIONConventional methods to achieve desired agronomic phenotypes such as increased yield, disease prevention, disease resistance, and improved abiotic stress tolerance have utilized mostly selective breeding, grafting, transgenic and agrochemical approaches.
Bioactive Priming Polypeptides Involved in Plant Defense Responses
Plants possess an immune system that detects and protects against microbes that can cause disease. Antimicrobial peptides (AMPs) in plants are often the first line of defense against invading pathogens and are involved in the initiation of defense responses that can impart innate immunity to a plant. Many AMPs are generically active against various kinds of infectious agents. They are generally classified as antibacterial, anti-fungal, anti-viral and/or anti-parasitic.
The resistance of given plant species against certain pathogenic organisms that can contact a plant surface and colonize it, is based on highly specialized recognition systems for molecules produced only by certain microbes (for example, specific bacterial or fungal strains). Plants sense potential microbial invaders by using pattern-recognition receptors (PRRs) to recognize the pathogen-associated molecular patterns (PAMPs) associated with them.
Flagellin/Flagellin-Associated Polypeptides
Flagellins and flagellin-associated polypeptides derived from those flagellins have been reported primarily to have functional roles in innate immune responses in plants. These polypeptides are derived from highly conserved domains of eubacterial flagellin. Flagellin is the main building block of the bacterial flagellum. The flagellin protein subunit building up the filament of bacterial flagellum can act as a potent elicitor in cells to mount defense-related responses in various plant species.
“Flagellin” is a globular protein that arranges itself in a hollow cylinder to form the filament in a bacterial flagellum. Flagellin is the principal substituent of bacterial flagellum, and is present in flagellated bacteria. Plants can perceive, combat infection and mount defense signaling against bacterial microbes through the recognition of conserved epitopes, such as the stretch of 22 amino acids (Flg22) located in the N-terminus of a full length flagellin coding sequence. The elicitor activity of Flg22 polypeptide is attributed to this conserved domain within the N-terminus of the flagellin protein (Felix et al., 1999). Plants can perceive bacterial flagellin through a pattern recognition receptor (PRR) at the plant's cell surface known as flagellin sensitive receptor, which is a leucine-rich repeat receptor kinase located in the plasma membrane and available at the plant cell surface. In plants, the best-characterized PRR is FLAGELLIN SENSING 2 (FLS2), which is highly conserved in both monocot and dicot plants.
In Arabidopsis, the innate immune response to Flg22 involves a host recognition protein complex that contains the FLS2 leucine rich repeat (LRR) receptor kinase (Gómez-Gómez L. and Boller T., “FLS2: An LRR receptor-like kinase involved in the perception of the bacterial elicitor flagellin in Arabidopsis,” Molecular Cell 5: 1003-1011, 2000). In Arabidopsis thaliana, FLS2 is a PRR that determines flagellin perception and is specific for the binding of the flagellin-associated polypeptide(s). For example, the binding of Flg22 to the outer plant FLS2 membrane-bound receptor triggers a signaling cascade that is involved in the innate immune response that induces the plant to mount a highly specific signaling-associated cascade that is involved in the activation of pattern-triggered immunity (Chinchilla et al., “The Arabidopsis receptor kinase FLS2 binds Flg22 and determines the specificity of flagellin perception,” Plant Cell 18: 465-476, 2006). Thus, the binding of Flg22 to the Arabidopsis FLS2 membrane-bound receptor promotes the first step of activation in which the binding elicits an activation cascade for defense responses in the plant. The Flg22-FLS2 interaction can also lead to the production of reactive oxygen species (ROS) that contribute to the induction of an oxidative burst, cellular medium alkalinization, downstream induction of pathogen-responsive genes and defense-related responses which then can impart disease resistance to a plant (Felix G. et al., “Plants have a sensitive perception system for the most conserved domain of bacterial flagellin,” The Plant Journal 18: 265-276, 1999, Gómez-Gómez L. and Boller T., “FLS2: An LRR receptor-like kinase involved in the perception of the bacterial elicitor flagellin in Arabidopsis,” Molecular Cell 5: 1003-1011, 2000, Meindi et al., “The bacterial elicitor flagellin activates its receptor in tomato cells according to the address-message concept,” The Plant Cell 12: 1783-1794, 2000). In tomato, high affinity binding of Flg22 to a FLS receptor was observed using both intact cells as well as to microsomal membrane preparations. In this study, the binding of Flg22 to the FLS2 receptor(s) at the plasma membrane surface was nonreversible under physiological conditions, which reflects an uptake process of the Flg22 elicitor with import into the tomato cells (Meindi et al., “The bacterial elicitor flagellin activates its receptor in tomato cells according to the address-message concept,” The Plant Cell 12: 1783-1794, 2000). Recognition of Flg22 by FLS2 triggers both local and systemic plant immune responses. The Flg22-bound, activated FLS2 receptor complex is internalized into plant cells by endocytosis and moves systemically throughout the plant (Jelenska et al., “Flagellin peptide flg22 gains access to long-distance trafficking in Arabidopsis via its receptor, FLS2,” Journal of Experimental Botany 68: 1769-1783, 2017), which may contribute towards systemic Flg22 immune responses.
Flagellin receptor perception mediation involving Flg22 is highly conserved across divergent plant taxa (Taki et al., “Analysis of flagellin perception mediated by flg22 receptor OsFLS2 in rice,” Molecular Plant Microbe Interactions 21: 1635-1642, 2008). Submicromolar concentrations of synthetic polypeptides comprising between 15-22 or 28 amino acids from conserved domains of a flagellin protein, act as elicitors to initiate defense responses in a variety of plant species.
Generation of transgenic plants has been used to confirm the flagellin-specific PAMPs that bind to the flagellin-specific PRRs. Ectopic expression of FLS2 in Arabidopsis plants showed a direct correlation between the flagellin responses and FLS2 expression levels, which indicate that FLS2 is involved in the recognition of flagellin (a signal of bacterial presence) and leads to the activation of defense responses in plants (Gómez-Gómez L. and Boller T., “FLS2: An LRR receptor-like kinase involved in the perception of the bacterial elicitor flagellin in Arabidopsis,” Molecular Cell 5: 1003-1011, 2000). Transgenic plants expressing the flagellin binding receptor have shown efficacy against certain pathogens. Flagellin binding to FLS2 was involved in the initiation of expression of specific MAP kinase transcription factors that function downstream of the flagellin receptor FLS2. Mutant plants (fls2) lacking in the FLS2 receptor are insensitive to Flg22 (Gómez-Gómez L. and Boller T., “FLS2: An LRR receptor-like kinase involved in the perception of the bacterial elicitor flagellin in Arabidopsis,” Molecular Cell 5: 1003-1011, 2000), and impaired in Flg22 binding to the FLS2 receptor. Mutant plants (fls2) also exhibited enhanced susceptibility to infection and disease when treated with pathogenic bacteria (Zipfel et al., “Bacterial disease resistance in Arabidopsis through flagellin perception,” Nature 428: 764-767, 2004).
Traditionally, methods to improve disease resistance have capitalized on these and other such findings and have taken a transgenic approach. Transgenic plants and seeds transformed with a Flagellin-Sensing (FLS) receptor protein (WO2016007606A2 incorporated herein by reference in its entirety) or with transcription factors involved in downstream signaling of FLS (WO2002072782A2 incorporated herein by reference in its entirety) have produced plants that confer disease resistance to certain pathogenic microorganisms. In another example, transgenic plants expressing Flagellin-Sensing (FLS3) receptor also have exhibited enhanced resistance to disease compared to non-transgenic plants not expressing the FLS3 receptor (WO2016007606A2 incorporated herein by reference in its entirety).
Plant Defensins/Thionins
Plant defensins are also characterized as anti-microbial peptides (AMPs). Plant defensins contain several conserved cysteinyl residues that form disulphide bridges and contribute to their structural stability. Defensins are among the best characterized cysteine-rich AMPs in plants. Members of the defensin family have four disulfide bridges that fold into a globular structure. This highly conserved structure bestows highly specialized roles in protecting plants against microbial pathogenic organisms (Nawrot et al., “Plant antimicrobial peptides,” Folia Microbiology 59: 181-196, 2014).
Thionins are cystine-rich plant AMPs classified in the defensin family and typically comprise 45-48 amino acid residues, in which 6-8 of these amino acids are cysteine that form 3-4 disulfide bonds in higher plants. Thionins have been found to be present in both monocot and dicot plants and their expression can be induced by infection with various microbes (Tam et. al., “Antimicrobial peptides from plants,” Pharmaceuticals 8: 711-757, 2015). Particular amino acids of thionins such as Lys1 and Tyr13, which are highly conserved, have been found to be vital to the functional toxicity of these AMPs.
Harpin and Harpin-Like (HpaG-Like)
Similar to the flagellins or the flagellin-associated polypeptides, harpins comprise a group of bacterial-derived elicitors that are derived from larger precursor proteins. Harpins are critical for the elicitation of a hypersensitive response (HR) when infiltrated into the intercellular space or apoplast of plant cells (Kim et al., “Mutational analysis of Xanthomonas harpin HpaG identifies a key functional region that elicits the hypersensitive response in nonhost plants,” Journal of Bacteriology 186: 6239-6247, 2004). Application of the distant harpin-like (HpaG-like) bioactive priming polypeptide(s) to a plant provides an alternative conduit to protect a plant from disease and insect pressure. Harpins utilize a type III secretion system that enable the transport of proteins across the lipid bilayers that makeup the plant plasma cell membrane. The binding of harpins to the surface of the plasma cell membrane can trigger an innate immune response that resembles those triggered by pathogen-associated molecular patterns (PAMPs) and are known to activate PAMP-triggered immunity (Engelhardt et al., “Separable roles of the Pseudomonas syringae pv. phaseolicola accessory protein HrpZ1 in ion-conducting pore formation and activation of plant immunity,” The Plant Journal 57: 706-717, 2009). Mutational analysis of a harpin-like HpaG derived polypeptide showed that the 12 amino acid residues between Leu-39 and Leu50 of the original 133 amino acid harpin elicitor precursor protein was critical to the elicitation of a hypersensitive (HR) and subsequent innate immune responses in tobacco (Kim et al., “Mutational analysis of Xanthomonas harpin HpaG identifies a key functional region that elicits the hypersensitive response in nonhost plants,” Journal of Bacteriology 186: 6239-6247, 2004). This indicates that a specific amino acid region of harpins (similar to the other AMPs) is responsible for the elicitation responses. Harpins, such as HpaG-like can be used to enhance resistance to not only plant pathogens but also to insects (Choi et al., “Harpins, multifunctional proteins secreted by gram-negative plant pathogenic bacteria,” Molecular Plant Microbe Interactions 26: 1115-1122, 2013). Harpin has been used to induce disease resistance in plants and protect plants from colonization and feeding by insect phloem-feeding insects, such as aphids (Zhang et al., “Harpin-induced expression and transgenic overexpression of phloem protein gene At.PP2A1 in Arabidopsis repress phloem feeding of the green peach aphid Myzus persicae,” BMC Plant Biology 11: 1-11, 2011).
Elongation Factor Tu (EF-Tu)
Elongation factor Tu is an abundant protein found in bacteria and acts as a pathogen-associated molecular pattern (PAMP) to initiate signaling cascades that are involved in plant disease resistance and plant innate immunity to microbial pathogenic organisms. Interestingly, some EF-Tu polypeptides are also found to exist in plants. The first 18 amino acid residues of the N-terminus of EF-Tu from Escherichia coli, termed elf18, is known to be a potent inducer of PAMP-triggered immune responses in plants (Zipfel et al., “Perception of the bacterial PAMP EF-Tu by the Receptor EFR restricts Agrobacterium-mediated transformation,” Cell 125: 749-760, 2006). Polypeptides derived from E. coli EF-Tu are perceived by the plant cell-surface localized receptor EF-Tu receptor (EFR) (Zipfel et al., 2006). EF-Tu binding and activation of EFR follow a similar mode of action compared to that of the Flg peptide-FLS2 receptor complex (Mbengue et al., “Clathrin-dependent endocytosis is required for immunity mediated by pattern recognition receptor kinases,” Proc Natl Acad Sci U.S.A. 113: 11034-9, 2016).
Growth Altering Bioactive Priming Polypeptides
Phytosulfokines (PSKα)
Phytosulfokines (PSK) belong to a group of sulfated plant polypeptides that are encoded by precursor genes that are ubiquitously present and highly conserved in higher plants (Sauter M., “Phytosulfokine peptide signaling,” Journal of Experimental Biology 66: 1-9, 2015). PSK genes are encoded by small gene families that are present in both monocots and dicots and encode a PSK polypeptide(s) that can be active as either a pentapeptide or a C-terminally truncated tetrapeptide (Lorbiecke R, Sauter M, “Comparative analysis of PSK peptide growth factor precursor homologs,” Plant Science 163: 348-357, 2002).
The phytosulfokine protein is targeted to the secretory pathway in plants by a conserved signal polypeptide (Lorbiecke R, Sauter M, “Comparative analysis of PSK peptide growth factor precursor homologs,” Plant Science 163: 348-357, 2002). Processing of the phytosulfokine precursor protein involves sulfonylation by a tyrosylprotein sulfotransferase within the plant secretory pathway, specifically the trans-Golgi followed by secretion and proteolytic cleavage in the apoplast in order to produce PSK (Sauter M., “Phytosulfokine peptide signaling,” Journal of Experimental Biology 66: 1-9, 2015). After PSK is processed from the larger precursor polypeptide, the polypeptide undergoes tyrosine sulphation (Ryan et al., “Polypeptide hormones,” The Plant Cell Supplement, S251-S264, 2002). The secreted polypeptide is then perceived at the cell surface by a membrane-bound receptor kinase of the leucine-rich repeat family (Sauter M., “Phytosulfokine peptide signaling,” Journal of Experimental Biology 66: 1-9, 2015 where PSK can then bind to the specialized PSK receptor (for example, PSK1 from Arabidopsis) which has a leucine-rich repeat region located on the plant plasma membrane surface. Specific binding of PSK was detected in plasma membrane fractions from cell suspension cultures derived from rice and maize and the binding to the receptor was shown to initiate and stimulate cell proliferation (Matsubayashi et al., “Phytosulfokine-α, a sulfated pentapeptide, stimulates the proliferation of rice cells by means of specific high- and low-affinity binding sites,” Proceedings National Academy of Science USA 94:13357-13362, 1997).
Phytosulfokines (PSK) serve as sulfated growth factors with biostimulant activities and are involved in the control of the development of root and shoot apical meristems, growth regulation and reproductive processes. PSKs have also been reported to initiate cell proliferation, differentiation of quiescent tissues and are involved in the formation and stimulation and differentiation of tracheary elements (Matsubayashi et al., “The endogenous sulfated pentapeptide phytosulfokine-α stimulates tracheary element differentiation of isolated mesophyll cells of zinnia, Plant Physiology 120: 1043-1048, 1999). PSK signaling has also been reported to be involved in the regulation of root and hypocotyl elongation that occurs in Arabidopsis seedlings (Kutschmar et al., “PSK-α promotes root growth in Arabidopsis,” New Phytologist 181: 820-831, 2009).
Root Hair Promoting Polypeptide (RHPP)
Root hair promoting polypeptide (RHPP) is a 12 amino acid fragment derived from soybean Kunitz trypsin inhibitor (KTI) protein, which was detected from soybean meal that was subjected to degradation using an alkaline protease from Bacillus circulans HA12 (Matsumiya Y. and Kubo M. “Soybean and Nutrition, Chapter 11: Soybean Peptide: Novel plant growth promoting peptide from soybean,” Agricultural and Biological Sciences, Sheny H. E. (editor), pgs. 215-230, 2011). When applied to soybean roots, RHPP was shown to accumulate in the roots and promote root growth through the stimulation of cell division and root hair differentiation in Brassica.
SUMMARY OF THE INVENTIONA polypeptide is provided for bioactive priming of a plant or a plant part to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture. The polypeptide comprises either:
(a) a flagellin or flagellin-associated polypeptide and an amino acid sequence of the flagellin or flagellin-associated polypeptide comprises any one of SEQ ID NOs: 226, 1-225, 227-375, 526, 528, 530, 532, 534, 536, 538, 540, 541, 751 and 752; or
(b) a mutant flagellin or flagellin-associated polypeptide and an amino acid sequence of the mutant flagellin or flagellin-associated polypeptide comprises any one of SEQ ID NOs: 571-579 and 753; or
(c) a mutant flagellin or flagellin-associated polypeptide and an amino acid sequence of the mutant flagellin or flagellin-associated polypeptide comprises any one of SEQ ID NOs: 580-585; or
(d) a retro inverso Flg22 polypeptide and an amino acid sequence of the retro inverso Flg22 polypeptide comprises any one of SEQ ID NOs: 376-450, 527, 531, 533, 535, 537 and 539; or
(e) a retro inverso FlgII-28 polypeptide and an amino acid sequence of the retro inverso FlgII-28 polypeptide comprises any one of SEQ ID NOs: 451-525; or
(f) a retro inverso Flg15 polypeptide and an amino acid sequence of the retro inverso Flg15 polypeptide comprises SEQ ID NO: 529; or
(g) a harpin or harpin-like polypeptide and an amino acid sequence of the harpin or harpin-like polypeptide comprises any one of SEQ ID NOs: 587, 589, 591, 593, 594 and 595; or
(h) a retro inverso harpin or harpin-like polypeptide and an amino acid sequence of the retro inverso harpin or harpin-like polypeptide comprises any one of SEQ ID NOs: 588, 590, 592, 596 and 597; or
(i) a root hair promoting polypeptide (RHPP) and an amino acid sequence of the RHPP comprises any one of SEQ ID Nos: 600, 603 and 604; or
(j) a Kunitz Trypsin Inhibitor (KTI) polypeptide and an amino acid sequence of the KTI polypeptide comprises SEQ ID No: 602; or
(k) a retro inverso root hair promoting polypeptide (RI RHPP) and an amino acid sequence of the RI RHPP comprises any one of SEQ ID NO: 601, 605 and 606; or
(l) an elongation factor Tu (EF-Tu) polypeptide and an amino acid sequence of the EF-Tu polypeptide comprises any one of SEQ ID NOs: 607-623; or
(m) a retro inverso elongation factor Tu (RI EF-Tu) polypeptide and an amino acid sequence of the RI EF-Tu polypeptide comprises any one of SEQ ID NOs: 624-640; or
(n) a fusion polypeptide comprising SEQ ID NO: 750; or
(o) a phytosulfokine (PSK) polypeptide and an amino acid sequence of the PSK polypeptide comprises SEQ ID NO: 598; or
(p) a retro inverso phytosulfokine (RI PSK) polypeptide and an amino acid sequence of the RI PSK polypeptide comprises SEQ ID NO: 599; or
(q) a thionin or thionin-like polypeptide and an amino acid sequence of the thionin or thionin-like polypeptide comprises any one of SEQ ID NOs: 650-749, and
optionally, wherein the flagellin or flagellin-associated polypeptide of (a), the mutant flagellin or flagellin-associated polypeptide of (c), the harpin or harpin-like polypeptide of (g), the PSK polypeptide of (o), and the thionin or thionin-like polypeptide of (q) either: contains a chemical modification; is a variant having an amino acid insertion, deletion, inversion, repeat, duplication, extension, or substitution within the amino acid sequence; is part of a fusion protein; or contains a protease recognition sequence.
A composition is provided for bioactive priming of a plant or a plant part to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture. The composition comprises either: the polypeptide as described above or any combination thereof, and an agrochemical or a carrier; or any combination of the polypeptides.
A seed coated with the polypeptide or the composition as described herein is also provided.
A recombinant microorganism that expresses or overexpresses a polypeptide is also provided. The polypeptide comprises the polypeptides as described above for the composition.
Methods are provided for increasing growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decreasing abiotic stress in the plant or the plant part and/or protecting the plant or the plant part from disease, insects and/or nematodes, and/or increasing the innate immune response of the plant or the plant part and/or changing plant architecture. The method can comprise applying the polypeptide or the composition as described herein to a plant, a plant part, or a plant growth medium or a rhizosphere in an area surrounding the plant or the plant part to increase growth, yield, health, longevity, productivity, and/or vigor of the plant or the plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change the plant architecture.
Alternatively, the method can comprise applying the polypeptide or the composition as described herein to a plant growth medium to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part to be grown in the plant growth medium and/or decrease abiotic stress in the plant or the plant part to be grown in the plant growth medium and/or protect the plant or the plant part to be grown in the plant growth medium from disease, insects and/or nematodes, and/or increase the innate immune response and/or change plant architecture of the plant or the plant part to be grown in the plant growth medium.
Another method comprises applying the recombinant microorganism as described herein to a plant, a plant part, or a plant growth medium or a rhizosphere in an area surrounding the plant or the plant part to increase growth, yield, health, longevity, productivity, and/or vigor of the plant or the plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change the plant architecture. The recombinant microorganism expresses the polypeptide and expression of the polypeptide is increased as compared to the expression level the polypeptide in a wild-type microorganism of the same kind under the same conditions.
A method of producing a polypeptide comprising producing a fusion protein comprising any polypeptide as described herein and an enterokinase (EK) cleavage site via fermentation, the enterokinase cleavage site enhancing activity and stability of the polypeptide.
When the articles “a,” “an,” “one,” “the,” and “said” are used herein, they mean “at least one” or “one or more” unless otherwise indicated.
The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
“Abiotic stress” as used herein is defined as an environmental condition that can have a negative impact on a plant. Abiotic stress can include: temperature (high or low) stress, radiation stress (visible or UV), drought stress, cold stress, salt stress, osmotic stress, nutrient-deficient or high metal stress, or water stress that results in water deficit, flooding or anoxia. Other abiotic stress factors include dehydration, wounding, ozone, and high or low humidity.
“Bioactive priming” refers to an effect of the polypeptides as described herein to improve a plant or a plant part. Bioactive priming can increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture.
A “bioactive priming polypeptide” as used herein may be used interchangeably with the term “priming agent(s)” and as described for the classes of polypeptides of the: flagellin and flagellin-associated polypeptides, harpin and harpin-like polypeptide (HpaG-like), thionins, elongation factor Tu (EF-Tu) and its polypeptides, phytosulfokine α (PSKα), kunitz trypsin inhibitor (KTI), and root hair promoting polypeptide (RHPP), as well as any retro inverso polypeptides thereof.
A “colorant” as used herein acts as a visual product identifier for product branding and application. Colorants can include, but are not limited to, dyes and pigments, inorganic pigments, organic pigments, polymeric colorants, and formulated pigment coating dispersions available in a variety of highly concentrated shades.
“Endogenously” applied as used herein refers to an application to the inside of a plant surface. Small bioactive priming polypeptides are particularly suited for signalling and communication within a plant. Inside a plant surface refers to a surface internal to any plant membrane or plant cell. Internal could be used to mean either extracellular or intracellular to a plant cell and is inclusive of xylem, phloem, tracheids, etc. Endogenous can refer to movement systemically or through a plant such as referring to cell to cell movement in a plant. Endogenous application can include delivery of bioactive priming polypeptides using recombinant endophytic bacteria or fungi, wherein the endophytic microorganism is delivered externally to the plant and through natural mechanisms moves internally to the plant.
“Exogenously” applied as used herein refers to an application to the outside of a plant surface. A plant surface can be any external plant surface, for example a plasma membrane, a cuticle, a trichome, a leaf, a root hair, seed coat, etc.
“-associated” or “-like” polypeptides as used herein refers to polypeptides derived from or structurally similar to the recited polypeptide but having an amino acid sequence and/or source distinct from the recited polypeptide. For example, the thionin-like protein from Brassica rapa (SEQ ID NO: 694) has a different sequence than thionin from Brassica napus (SEQ ID NOs 693) but is structurally and functionally similar.
A “foliar treatment” as used herein refers to a composition that is applied to the above ground parts or foliage of a plant or plant part and may have leaves, stems, flowers, branches, or any aerial plant part, for example, scion.
“Injection” as described herein can be used interchangeably with vaccination or immunization and provides a process whereby the bioactive priming polypeptides are delivered endogenously to a plant or plant part.
“Inoculation” means to deliver-bacteria or living microorganisms that produce the priming polypeptide to a plant or plant part. Inoculation can also refer to the delivery of the priming polypeptide for passive entry through the stomata or any opening in or on a plant or plant part. A “plant” refers to but is not limited to a monocot plant, a dicot plant, or a gymnosperm plant. The term “plant” as used herein includes whole plants, plant organs, progeny of whole plants or plant organs, embryos, somatic embryos, embryo-like structures, protocorms, protocorm-like bodies, and suspensions of plant cells. Plant organs comprise, shoot vegetative organs/structures (e.g., leaves, stems and tubers), roots, flowers and floral organs/structures (e.g., bracts, sepals, petals, stamens, carpels, anthers and ovules), seed including embryo, endosperm, and seed coat and fruit (the mature ovary), plant tissue (e.g., phloem tissue, vascular tissue, ground tissue, and the like) and cells (e.g., guard cells, egg cells, trichomes and the like). The class of plants that can be used in the methods described herein is generally as broad as the class of higher plants, specifically angio-sperms monocotyledonous (monocots) and dicotyledonous (dicots) plants and gymnosperms. It includes plants of a variety of ploidy levels, including aneuploid, polyploid, diploid, haploid, homozygous and hemizygous. The plants described herein can be monocot crops, such as, sorghum, maize, wheat, rice, barley, oats, rye, millet, and triticale. The plants described herein can also be dicot crops, such as apple, pear, peach, plum, orange, lemon, lime, grapefruit, kiwi, pomegranate, olive, peanut, tobacco, tomato, etc. Also, the plants can be horticultural plants such as rose, marigold, primrose, dogwood, pansy, geranium, etc.
A plant “biostimulant” is any substance or microorganism applied to a plant or a plant part that is used to enhance nutrition efficiency, abiotic stress tolerance and/or any other plant quality trait(s).
A “plant cell” as used herein refers to any plant cell and can comprise a cell at the plant surface or internal to the plant plasma membrane, for example, an epidermal cell, a trichome cell, a xylem cell, a phloem cell, a sieve tube element, or a companion cell.
A “plant part” as described herein refers to a plant cell, a leaf, a stem, a flower, a floral organ, a fruit, pollen, a vegetable, a tuber, a corm, a bulb, a pseudobulb, a pod, a root, a rhizome, a root ball, a root stock, a scion, or a seed.
A “polypeptide” as described herein refers to any protein, peptide or polypeptide.
“Priming” or “peptide priming” as used herein refers to a technique used to improve plant performance. In particular priming is a process whereby the bioactive priming polypeptides are applied either exogenously or endogenously to a plant, plant part, plant cell or to the intercellular space of a plant that results in outcomes that provide benefits to a plant, such as enhanced growth, productivity, abiotic stress tolerance, pest and disease tolerance or prevention.
A “retro-inverso” polypeptide as used herein refers to a polypeptide chain of a natural derived polypeptide from a normal-all-L chain reconfigured and built using non-naturally occurring D-amino acids in reverse order of the naturally occurring L-amino acids. The all-D-amino acid form and the parent chain containing all L-form are topological mirrorings of the protein structure.
A “seed treatment” as used herein refers to a substance or composition that is used to treat or coat a seed. Sample seed treatments include an application of biological organisms, chemical ingredients, inoculants, herbicide safeners, micronutrients, plant growth regulators, seed coatings, etc. provided to a seed to suppress, control or repel plant pathogens, insects, or other pests that attack seeds, seedlings or plants or any useful agent to promote plant growth and health.
A “synergistic” effect refers to an effect arising between the interaction or cooperation of two or more bioactive priming polypeptides, substances, compounds, or other agents to produce a combined effect greater than the sum of their separate effects.
A “synergistic effective concentration” refers to the concentration(s) of two or more bioactive priming polypeptides, substances, compounds or other agents that produces an effect greater than the sum of the individual effects.
DESCRIPTION OF THE PREFERRED EMBODIMENTSThere is a growing need for bioactive polypeptides that act as “priming agents” to provide benefits to agriculture. The use of bioactive “priming” polypeptides in agricultural practices provides a paradigm shift for integrated crop management practices for example, to manage disease, abiotic stress and yield programs. Bioactive (naturally occurring, recombinant or synthetic) priming polypeptides are delivered in agricultural formulations. Compositions and methods of using the bioactive priming polypeptides are described to supply a multi-tiered treatment regime to apply to crops to achieve agronomically desirable outcomes. Such desirable outcomes include enhanced phenotypes in plants such as those that exhibit protection against pest, disease agents and abiotic stress, as well as increased plant growth, productivity and yield. More specifically, the bioactive priming polypeptides or formulations of the bioactive priming polypeptides can be applied using various treatment regimes, exogenously and/or endogenously to a plant or plant part, and have been discovered to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture.
Specific classes of synthetically derived or naturally occurring bioactive priming polypeptides including flagellins and flagellin-associated polypeptides (including those conserved among the Bacillus genera), thionins, harpin-like polypeptide (HpaG-like), elongation factor Tu (EF-Tu), phytosulfokine (PSKα) and root hair promoting polypeptide (RHPP) were selected for their distinct modes of action and can be used individually or in combination with other polypeptides to accommodate the specific agricultural needs described above. They can be used in the place of or in addition to commercially available agrochemicals, biostimulants, supplemental bioactives and/or pesticidal compounds.
Combinations of the bioactive priming polypeptides are also provided that are applied in synergistically effective amounts to provide control of pests, pathogens and additionally provide benefits to enhance plant growth and promote plant health.
I. PolypeptidesThe bioactive priming polypeptides are provided as naturally occurring, recombinant or chemically synthesized forms derived from bacteria or plants. The bioactive priming polypeptides are provided in both the normal L and non-natural retro-inverso D amino-acid forms. In addition, bioactive priming polypeptides are provided that contain non-natural modifications, including N-terminal and C-terminal modifications, cyclization, β-amino and D-amino acid containing, and other chemical modifications that enhance stability or performance of the polypeptides. For example, flagellin and the Flg-associated polypeptides comprising 22 amino acids in length and derived from the full coding region of flagellin were initially isolated and identified from a proprietary genome assembled for bacterial strain, Bacillus thuringiensis 4Q7. These Flg22 derived polypeptides were provided in the standard (L) and retro-inverso (D) forms. They are described as Bt.4Q7Flg22 and retro-inverso (RI) Bt.4Q7Flg22. Other bacterial derived bioactive priming polypeptides are Ec.Flg22 (Escherichia coli), HpaG-like (Xanthomonas spp.), while the plant derived polypeptides include thionins (Citrus spp. and other plant species), PSKα (Arabidopsis thaliana and other plants), EF-Tu (both bacterial or plant derived) and RHPP (Glycine max).
The bioactive priming polypeptides can include full-length proteins and are provided as naturally occurring, synthetic or recombinant forms derived from bacteria or plants. For example, flagellin, EF-Tu, KTI, and HpaG can all be delivered to plants.
The bioactive priming polypeptides can also be delivered as fusion partners to other protein sequences, including protease cleavage sites, binding proteins, and targeting proteins for specific delivery to plants or plant parts.
Also provided are signature, signal anchor sorting and secretion sequences that can be naturally or chemically synthesized and targeting sequences, such as phloem-targeting sequences that are produced along with the bioactive priming polypeptide(s) using recombinant microorganisms and either used as fusion or assistance polypeptides with the bioactive priming polypeptides as described herein.
Non-naturally occurring polypeptides are also described herein. More specifically, a polypeptide is provided for bioactive priming of a plant or a plant part to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture. The polypeptide comprises either:
(a) a flagellin or flagellin-associated polypeptide and an amino acid sequence of the flagellin or flagellin-associated polypeptide comprises any one of SEQ ID NOs: 226, 1-225, 227-375, 526, 528, 530, 532, 534, 536, 538, 540, and 541; or
(b) a mutant flagellin or flagellin-associated polypeptide and an amino acid sequence of the mutant flagellin or flagellin-associated polypeptide comprises any one of SEQ ID NOs: 571-579; or
(c) a mutant flagellin or flagellin-associated polypeptide and an amino acid sequence of the mutant flagellin or flagellin-associated polypeptide comprises any one of SEQ ID NOs: 580-585; or
(d) a retro inverso Flg22 polypeptide and an amino acid sequence of the retro inverso Flg22 polypeptide comprises any one of SEQ ID NOs: 376-450, 527, 531, 533, 535, 537 and 539; or
(e) a retro inverso FlgII-28 polypeptide and an amino acid sequence of the retro inverso FlgII-28 polypeptide comprises any one of SEQ ID NOs: 451-525; or
(f) a retro inverso Flg15 polypeptide and an amino acid sequence of the retro inverso Flg15 polypeptide comprises SEQ ID NO: 529; or
(g) a harpin or harpin-like polypeptide and an amino acid sequence of the harpin or harpin-like polypeptide comprises any one of SEQ ID NOs: 587, 589, 591, 593, 594 and 595; or
(h) a retro inverso harpin or harpin-like polypeptide and an amino acid sequence of the retro inverso harpin or harpin-like polypeptide comprises any one of SEQ ID NOs: 588, 590, 592, 596 and 597; or
(i) a root hair promoting polypeptide (RHPP) and an amino acid sequence of the RHPP comprises any one of SEQ ID Nos: 600, 603 and 604; or
(j) a Kunitz Trypsin Inhibitor (KTI) polypeptide and an amino acid sequence of the KTI polypeptide comprises SEQ ID No: 602; or
(k) a retro inverso root hair promoting polypeptide (RI RHPP) and an amino acid sequence of the RI RHPP comprises any one of SEQ ID NO: 601, 605 and 606; or
(l) an elongation factor Tu (EF-Tu) polypeptide and an amino acid sequence of the EF-Tu polypeptide comprises any one of SEQ ID NOs: 607-623; or
(m) a retro inverso elongation factor Tu (RI EF-Tu) polypeptide and an amino acid sequence of the RI EF-Tu polypeptide comprises any one of SEQ ID NOs: 624-640; or
(n) a fusion polypeptide comprising SEQ ID NO: 750; or
(o) a phytosulfokine (PSK) polypeptide and an amino acid sequence of the PSK polypeptide comprises SEQ ID NO: 598; or
(p) a retro inverso phytosulfokine (RI PSK) polypeptide and an amino acid sequence of the RI PSK polypeptide comprises SEQ ID NO: 599; or
(q) a thionin or thionin-like polypeptide and an amino acid sequence of the thionin or thionin-like polypeptide comprises any one of SEQ ID NOs: 650-749, and
optionally, wherein the flagellin or flagellin-associated polypeptide of (a), the mutant flagellin or flagellin-associated polypeptide of (c), the harpin or harpin-like polypeptide of (g), the PSK polypeptide of (o), and the thionin or thionin-like polypeptide of (q) either: contains a chemical modification; is a variant having an amino acid insertion, deletion, inversion, repeat, duplication, extension, or substitution within the amino acid sequence; is part of a fusion protein; or contains a protease recognition sequence.
Flagellins and Flagellin-Associated Polypeptides
The polypeptide can include a flagellin or flagellin-associated polypeptide.
The flagellin or flagellin-associated polypeptide can be derived from a Bacillus, a Lysinibacillus, a Paenibacillus, an Aneurinibacillus genus bacterium, or any combination thereof.
One of the main classes of bioactive priming polypeptides as described herein are the flagellin(s) and the flagellin-associated priming polypeptide(s). Conserved full and partial length amino acid flagellin coding sequences were identified from various species of Bacillus and non-Bacillus bacteria using methods as described herein.
Flagellin is a structural protein that forms the main portion of flagellar filaments from flagellated bacterial species that can show conservation in the N-terminal and C-terminal regions of the protein but can be variable in the central or mid part (Felix G. et al., “Plants have a sensitive perception system for the most conserved domain of bacterial flagellin,” The Plant Journal 18: 265-276, 1999). The N- and C-terminal conserved regions from flagellins that form the inner core of the flagellin protein may have roles in the polymerization of the protein into a filament, in the motility and transport of the protein and in the surface attachment of a peptide fragment to the plant cell membrane/cell surface receptors of a plant.
Full or partial flagellins (Table 1-2) and the flagellin-associated polypeptides derived from those Bacillus and non-Bacillus flagellins (Tables 3 and 5) are provided.
The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 1-768, or any combination thereof.
Flagellin-associated bioactive priming polypeptides are produced from flagellin coding polypeptides (such as the precursor proteins of Flg22). More specifically, a polypeptide or a cleaved fragment derived from the polypeptide is provided to achieve a bioactive priming Flg polypeptide that can be used to prime or treat a plant. The cleavage of the Flg22 fragment from larger precursors can be accomplished through introduction of proteolytic cleavage sites near the Flg22 to facilitate processing of the active biopeptide from the larger polypeptide.
The flagellin-associated bioactive priming polypeptides can be derived from full length flagellin proteins (or precursor proteins from Flg-associated polypeptides from a Bacillus, a Lysinibacillus, a Paenibacillus, or an Aneurinibacillus or other non-related genera bacterium). For example, PCR purified DNA from the flagellin-associated polypeptides such as Flg22 and FlgII-28 (Bacillus genera) and Flg15 and Flg22 (E. coli) are cloned into a recombinant vector, amplified to achieve adequate amounts of purified DNA that is then sequenced using conventional methods known and used by one of ordinary skill in the art. The same methods can be used with the flagellin coding or the flagellin partial sequences (Table 1), N- or C-terminal flagellin polypeptides (Table 2) and any of the Flg-associated polypeptides (Tables 3-5).
The flagellin or flagellin-associated polypeptide can be derived from any member of Eubacteria that contains the conserved 22 amino acid region that is recognized by the plants. Preferred flagellin or flagellin-associated polypeptides can be derived from a Bacillus, a Lysinibacillus, a Paenibacillus, an Aneurinibacillus genus bacterium, or any combination thereof. Additional preferred flagellin and Flg22 sequences can be obtained from the gammaproteobacteria, which contain conserved 22 amino acid sequences of >68% identity.
Conserved Flagellin Sequences from Bacillus
The flagellin-associated bioactive priming polypeptides correspond to the N-terminal conserved domains of Bacillus spp. and other Eubacterial flagellin and are provided as synthetic, recombinant or naturally occurring forms. The flagellin bioactive priming polypeptides of Flg22, Flg15 and FlgII-28 (Table 3) were identified and act as potent elicitors on a wide range of crops and vegetables to prevent and treat the spread of select disease(s) while synergistically stimulating and promoting growth responses in plants.
The flagellin and flagellin-associated bioactive priming polypeptides as described herein are provided for use individually or in combination with other bioactive priming polypeptides as described herein, and include conserved full and partial flagellins from Bacillus (Table 1), conserved N- and C-terminal regions from flagellin polypeptides (Table 2), Bacillus derived Flg22 and FlgII-28-derived bioactive priming polypeptides (Table 3) and retro-inverso sequences that are mirror images derived from the Bacillus Flg22 and FlgII-28 (Table 4). The underlined portion of the sequences in Tables 1 and 3 represent identified signal anchor sorting or secretion sequences, and signal anchoring sequences, respectively. Other non-Bacillus derived polypeptide and proteins are also described that are functional equivalents and can be utilized in similar fashion (Table 5).
N- and C-Terminal Conserved Regions of Flagellin
The flagellin or flagellin-associated polypeptide can comprise a truncated N-terminal polypeptide and an amino acid sequence of the truncated N-terminal polypeptide can comprise SEQ ID NO: 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 109, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 160, 162, 164, 166, 168, 170, 172, 174, 176, 178, 180, 182, 184, 186, 188, 190, 192, 194, 196, 198, 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, 220, 222, 224, 752, or any combination thereof.
The flagellin or flagellin-associated polypeptide can comprise a truncated C-terminal polypeptide and an amino acid sequence of the truncated C-terminal polypeptide can comprise SEQ ID NO: 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, 181, 183, 185, 187, 189, 191, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, or any combination thereof.
N-terminal and C-terminal conserved regions were identified from full length flagellin sequences from diverse strains of Bacillus spp. and other Eubacteria (Table 2). Conserved N- and C-terminal domains were identified using BLAST multiple alignment software and assigned functional annotations based on individual hits searching against Bacillus and other Eubacterial bacterial databases. The start site for the N-terminal region of the coding sequences is bolded methionine (M). The conserved domains are provided as amino acid sequences N-terminus (left column) and C-terminus (right column).
The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 226-300, or any combination thereof.
The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise SEQ ID NO: 226.
The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 301-375, or any combination thereof.
The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise SEQ ID NO: 301.
The flagellin-derived polypeptide sequence for Bt4Q7Flg22 (SEQ ID NO: 226) was identified from a proprietary “In house” library from Bacillus thuringiensis (Bt.) strain 4Q7. Conserved primers to full length flagellin from E. coli were used to screen the Bt.4Q7 strain library and identify a functional flagellin-associated bioactive priming Flg22 polypeptide.
Retro-Inverso Flagellin-Associated Polypeptides
Bioactive Flg polypeptide(s) useful for priming can be created in a non-natural isomeric or retro-inverso (RI) form.
The retro-inverso Flg polypeptides can exhibit enhanced binding affinity for the FLS receptor protein(s). Plant flagellin receptors, like FLS2, can recognize a retro inverso Flg polypeptide fragment such as either Flg22 or FlgII-28 located within the N-terminal conserved domain of flagellin. The retro-inverso forms of these Flg polypeptides are provided as biologically active forms, which can recognize and interact with the Flg-associated or FLS receptor protein on the surface of the plant cell membrane.
Retro-inverso Flg polypeptides can possess an increased activity and stability to proteolytic degradation at the plant membrane surface. For example, retro inverso forms of Bacillus Flg22 or FlgII-28 polypeptides can increase activity and stability of the Flg polypeptide(s) and increase protection against proteolytic degradation at the plant surface or root surface. The retro inverso forms also exhibit enhanced stability when applied in a field, or on or in a soil.
Retro-inverso polypeptides are topological mirror images of the native structures of the parent polypeptide. Retro inverso synthetic forms of the polypeptide sequences are created by reversing the polypeptide sequences and using retro-all-D or retro-enantio-peptides. The all D-chain amino acid Flg polypeptide(s) adopts a “mirror image” of the three-dimensional structure of its related L-peptide or L-chain amino.
This is further accomplished by creating a retro-inverso alteration of any of the parent Flg polypeptide derived from Bacillus or other Eubacteria in Table 3. Retro-inverso polypeptides that were designed to the Flg22 (RI Flg22: SEQ ID NOs: 376-450), and FlgII-28 (RI-FlgII-28: SEQ ID NOs: 451-525) are provided in Table 4. Retro inverso forms of Ec.Flg22 (SEQ ID NO: 526) and EcFlg15 (SEQ ID NO: 529) as provided in Table 5 were also created from E. coli derived sequences.
The polypeptide can include a retro inverso Flg22 polypeptide.
The polypeptide can comprise a retro inverso FlgII-28 polypeptide.
Any of the flagellin-associated bioactive priming polypeptides comprising Bacillus or from other Eubacteria Flg22 or FlgII-28 polypeptides in Table 3 can be used in their retro-inversed forms (referenced in Table 4).
Retro inverso forms of the Flg bioactive priming polypeptides as referenced herein can be provided in any of three forms where the inversion of amino acid chirality contains the normal-all-D (inverso), all-L (retro) and/or retro-all-D (retro-inverso) or a combination of these forms to achieve the desired phenotypes in a plant.
The Bacillus-derived L-Flg22 and L-FlgII-28 polypeptides in Table 3 and the E.c. native L-Flg22 and L-Flg15 polypeptides in Table 5 were synthetically generated via retro-inverso engineering to form retro-inverso D-Flg22 polypeptide (SEQ ID NO: 376-450), D-FlgII-28 (SEQ ID NO: 451-525), and E.c. D-Flg22 polypeptide (SEQ ID NO: 527, 529).
The inversion of amino acid chirality (all-L to all-D) for Bt.4Q7 Flg22 (SEQ ID NO: 376), which is provided as a small linear polypeptide fragment and is referred to as a retro inverso modification was achieved by a reversal of the direction of the polypeptide backbone and described below.
The retro inverso all D-chain amino acid Flg22 polypeptide adopts a “mirror image” of the three-dimensional structure of its related native L-Bt.4Q7Flg 22 polypeptide and this all L-chain has an equivalent mirror image to the all D Bt.4Q7Flg22 polypeptide. All L-amino acid residues are replaced by their D-enantiomers leading to all D-peptides or retro all D-isomer-peptides containing amide linkages. The native L-amino acid chain form of Bt.4Q7 Flg22 polypeptide chain reversed to generate the retro-inverso synthetic all-D confirmation that is prepared by replacing all the L-amino acid residues with their corresponding D-enantiomers.
In the case of short polypeptides, such as Flg22, Flg15 and FlgII-28, the mirroring of the side chain positions in a conformational change from L-to-D conversion states results in a mirroring of symmetry transformations of the side chains as well.
Retro-all-D analogues have been found to possess biological activity (Guptasarma, “Reversal of peptide backbone direction may result in mirroring of protein structure, FEBS Letters 310: 205-210, 1992). The retro-inverso D-Flg polypeptide(s) can assume a side chain topology in its extended conformation that is similar to a corresponding native L-Flg polypeptide sequence, thus emulating biological activities of the native L-parent molecule while fully resistant to proteolytic degradation thus increasing stability when the polypeptide contacts the plant or the surrounding environment.
Retro-inverso Flg bioactive priming polypeptides are described in Table 4 or Table 5. Retro inverso Flg-associated bioactive priming polypeptides provided in Table 4 were selected for their enhanced activity and stability and their ability to survive under varying conditions and environments. Based on their D enantiomer nature, they are more resistant to proteolytic degradation and can survive and exist in harsher environmental conditions.
Flg Sequences from Various Organisms
Sequences that Assist in Directing Flagellins or Flagellin-Associated Polypeptides to the Plant
The signature, signal anchor sorting and secretion sequences can be used separately or together in combination with any of the flagellin or flagellin-associated polypeptides as described herein. These assistance sequences are useful for the efficient delivery of the flagellin polypeptides to the plant cell membrane surface. Other assistance sequences can also assist with the translocation of the Flg polypeptide fragment across the plasma membrane. Delivery of flagellins and flagellin-associated polypeptides to the plasma membrane surface of a plant (or plant part) can contribute to downstream signalling processes and result in beneficial outcomes to a plant or a plant part, such as enhanced plant health and productivity.
The polypeptide can further comprise an assistance polypeptide.
The assistance polypeptide can comprise a signature polypeptide, and an amino acid sequence of the signature polypeptide can comprise any one of SEQ ID NOs: 542-548, listed in Table 6, or any combination thereof. For example, the amino acid sequence of the signature polypeptide can comprise SEQ ID NO: 542.
The assistance polypeptide can comprise a signal anchor sorting polypeptide, and an amino acid sequence of the signal anchor sorting polypeptide can comprise any one of SEQ ID NOs: 549-562, listed in Table 7, or any combination thereof. For example, the amino acid sequence of the signal anchor sorting polypeptide can comprise SEQ ID NO: 549.
The flagellin or flagellin-associated polypeptide can be produced recombinantly by a microorganism. For example, the microorganism can comprise a Bacillus, a Pseudomonas, a Paenibacillus, Aneurinibacillus or a Lysinibacillus.
The assistance polypeptide can comprise a secretion polypeptide, and an amino acid sequence of the secretion polypeptide can comprise any one of SEQ ID NOs: 563-570, or any combination thereof. For example, the amino acid sequence of the secretion polypeptide can comprise SEQ ID NO: 563.
These three types of assistance sequences are further described in Table 6 (N-terminal signature sequences), Table 7 (signal anchor sorting sequences) and Table 8 (secretion sequences).
Also provided are “assistance” sequences having conserved signature (Table 6; SEQ ID NOs: 542-548), signal anchor sorting (Table 7; SEQ ID NOs: 549-562) and secretion (Table 8; SEQ ID NOs: 563-570) sequences in combination with any of the flagellin-associated polypeptides as described herein. Particularly useful are combinations of the signature, signal anchor sorting and secretion assistance sequences with the native L-Flg polypeptides (Table 3. SEQ ID NOs: 226-375) or any of the retro inverso Flg22 polypeptides (Table 4. SEQ ID NOs: 376-525) for providing efficient delivery of the Flg polypeptides to the extracellular plant membrane surface, such as the surface of a plant or plant part.
N-Terminal Signature Sequences
Amino acid “signature” sequences conserved within Bacillus, Lysinibacillus, Paenibacillus or Aneurinibacillus bacteria (genera) and other Eubacterial generas can function in targeting flagellin polypeptides to the appropriate Flg-associated receptor protein(s), such as FLS receptors that have an exposed binding site at the plant cell membrane surface and can be used to enhance Flg polypeptide-receptor binding leading to an increased activation potential of the Flg-associated receptor(s). Flagellin signature sequences as identified in Table 6 are useful for targeting and stably delivering the Flg polypeptides for binding to the FLS or FLS-like receptor(s) therefore increasing the contact and binding between the membrane receptor and the Flg polypeptide.
Conserved N-terminal signature sequences (SEQ ID NO: 542-548) can be used in combination with any of the flagellin-associated polypeptides as described herein. Of particular utility are the signature sequences used in combination with the native L-Flg polypeptides (L-Flg22 SEQ ID NOs: 226-300; L-FlgII-28 SEQ ID NOs: 301-375) or any of the retro inverso D-Flg polypeptides (D-Flg22 SEQ ID NOs: 376-450; FlgII-28 SEQ ID NO: 451-525) or any of the other Flg-associated sequences provided in Table 5 (SEQ ID NOs: 526-541) to provide efficient delivery of the Flg-associated polypeptides to the plant membrane surface.
Signature sequences assist with Flg22 and FlgII-28 bioactive priming polypeptide sequences in binding to the appropriate Flg-associated receptor(s) in order to activate the receptor(s) making it functionally active.
N-Terminal Signal Anchor Sorting Sequences
Amino acid “signal anchor sorting” sequences conserved within Bacillus, Lysinibacillus, Aneurinibacillus and Paenibacillus genera and other Eubacterial generas' bacteria can function in anchoring and localizing the flagellin-associate polypeptides to the plant cell membrane surface and assist in high affinity binding to the appropriate Flg-associated receptor(s) thereby increasing the activation potential of the bound receptor(s).
Conserved signal anchor sequences (SEQ ID NO: 549-562; Table 7) are located downstream of the pre-cleaved or full-length coding or partial coding flagellin sequences, for example, as described herein (SEQ ID NOs: 1-75; Table 1).
The signal anchor sorting domains as described herein are useful in membrane attachment. They can be used to aid in the localization and binding of Flg-associated polypeptides to a surface membrane receptor and have some functional similarity at the amino acid level to proteins that are endosomal (vesicular) trafficked or destined for targeting to the secretory pathway. Such signal anchor sorting sequences as described herein that are useful for anchoring the Flg bioactive priming polypeptides to the plant cell membrane are also used to enhance the membrane integration of the bioactive priming Flg polypeptides into the plant cell.
Such sequences as described in Table 7 may further be functionally annotated as import receptor signal anchor sequences, which can be used to improve targeting or delivery and efficient membrane anchoring of Flg-associated polypeptides to a plant and assist with membrane integration into the cytosol of the plant cell.
Combining the signal anchor sequences (SEQ ID NOs: 549-562; Table 7) with any of the flagellins or flagellin-associated bioactive priming polypeptides as described herein is useful to facilitate the attachment and import of these flagellin-associated polypeptide(s) into the plant.
Such signal anchor sorting sequences can be used in combination with the Flg-associated polypeptides, and are useful for targeting, efficient membrane anchoring, membrane integration and Golgi-to-lysosomal/vacuolar trafficking. The signal anchor sorting sequences are used to stably deliver the Flg polypeptides to the plant membrane surface and integrally incorporate them into the plant.
Such sequences as described herein contain di-leucine amino acids that are referenced to confer endocytosis functionalities in plant systems (Pond et al. 1995, “A role for acidic residues in di-leucine motif-based targeting to the endocytic pathway”, Journal of Biological Chemistry 270: 19989-19997, 1995).
Such signal anchor sorting sequences as described can also be used to efficiently deliver systemic signals to infection sites and stimulate a plant's innate immunity in plant cells.
C-Terminal Secretion Sequences
Conserved sequences located in the C-terminus of flagellin(s) are further described as secretion sequences (SEQ ID NO: 563-570; Table 8).
Conserved sequences were identified in the C-terminus of the Bacillus, Lysinibacillus, and Paenibacillus bacteria (genera) and other Eubacterial genera derived flagellin proteins and comprise 6 amino acids, for example LGATLN, LGSMIN, or LGAMIN. These sequences were functionally annotated using BLAST against the bacterial databases as motifs that have highest homology to secretion polypeptides. The 6 amino acid conserved polypeptides identified were found most similar to those found in type III secretion systems in E. coli. Type III export systems have been cited to be involved in the translocation of polypeptides across the plant cell membrane. The filament assembly of flagellin is dependent on the availability of flagellins to be secreted and may require chaperones that assist in the secretory process.
These secretion polypeptides as described herein may be used in combination with any of the flagellin-associated polypeptides as described herein to deliver these polypeptides/peptides into the cytosol of the host plant thus providing beneficial outcomes to a plant.
The signature (SEQ ID NO: 542-548; Table 6), signal anchor sorting (SEQ ID NO: 549-562; Table 7) and secretion (SEQ ID NO: 563-570; Table 8) sequences as provided herein can be used with any of the flagellin polypeptides or the flagellin-associated polypeptides to promote growth and provide health and protective benefits to a plant or a plant part.
Modification of Flg Polypeptide Sequences FunctionAny of the L or D Flg-associated sequences provided in Tables 3, 4 or 5 can be similarly modified as fused to any of the assistance sequences as described in Table 6-8. For one example, fusion of any of these assistance sequences will present a modification to the Bt.4Q7Flg22 bioactive priming polypeptide sequence identified as SEQ ID NO: 226.
Mutations to Flg-Associated Polypeptides to Increase Responsiveness to Reactive Oxygen Species or Polypeptide StabilityThe polypeptide can comprise a mutant flagellin or flagellin-associated polypeptide.
The mutant flagellin or flagellin-associated polypeptide can be derived from a Bacillus, a Lysinibacillus, a Paenibacillus, or an Aneurinibacillus genus bacterium. Other polypeptides from other Eubacterial classes, including Enterobacteraciae, can also be used in the same fashion. Other generas of interest include Pseudomonas, Escherichia, Xanthomonas, Burkholderia, Erwinia, and others.
The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 226, 289, 290, 291, 293, 294, 295, 300, 437, 532, 534, 536, 538, 540, 571-586 and 751-768. For example, the amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 226, 293, 295, 300, 540, 571, 574 and 752, or any combination thereof.
Any bioactive priming polypeptide, whether naturally occurring or non-natural, can be further modified via chemical modification to increase performance as well as stability of the polypeptides. Such bioactive priming polypeptides include flagellin polypeptides, retro inverso polypeptides, harpin derived polypeptides, harpin-like derived polypeptides, EF-Tu polypeptides, thionin polypeptides, RHPP polypeptides, and PSK polypeptides. Specific sequences that can be chemically modified include SEQ ID NOs: 226-592, 594-601, 603-749, and 751-766.
These bioactive priming polypeptides can also be conjugated to other moieties, including a plant binding domain and a polypeptide, a plant part binding domain and a polypeptide, and other carriers such as oils, plastics, beads, ceramic, soil, fertilizers, pellets, and most structural materials.
The flagellin or flagellin-associated polypeptide can be modified chemically on its N or C terminus. Common modification of the N and C-termini include: acetylation, lipid addition, urea addition, pyroglutamyl addition, carbamate addition, sulfonamide addition, alkylamide addition, biotinylation, phosphorylation, glycosylation, PEGylation, methylation, biotinylation, acid addition, amide addition, ester addition, aldehyde addition, hydrazide addition, hydroxyamic acid addition, chloromethyl ketone addition, or addition of purification tags. These tags can increase activity of the polypeptides, increase stability, add protease inhibitor abilities to the polypeptides, block proteases directly, allow for tracking, and help in binding to plant tissues.
The flagellin or flagellin-associated polypeptide can be modified via crosslinking or cyclization. Crosslinking can bind polypeptides either to each other or to a secondary surface or moiety to help in delivery or stability of the polypeptides. Cyclization can be performed, for example, to both increase activity of the polypeptide as well as prevent protease interaction with the polypeptide.
Sequence modifications or mutations can be made to any amino acid sequence(s) as described in Tables 4 and 5 and replaced with any of the 20 standard amino acid sequences known in nature or replaced with a nonstandard or non-canonical amino acid sequence, such as selenocysteine, pyrrolysine, N-formylmethione, etc. For example, modifications or mutations can be made to the internal sequences as shown in SEQ ID NO: 571, to the C-terminis as shown in SEQ ID NO: 572 or SEQ ID NO: 753, or to the N terminus as shown in SEQ ID NO: 573 to produce Flg polypeptides with enhanced ROS activates and increased functionality in a plant or plant part. Modified polypeptides also can be truncated at the N or C terminus as shown in SEQ ID NO: 752 (N-terminus truncation) to further increase functionality in a plant or plant part. Table 9A summarizes flagellin polypeptides identified that provide modified ROS activity.
The underlined portions of the sequences in Table 9A represent the core active domain of Flg22. This core domain comprises, for example, SEQ ID NO: 754 with up to one, two or three amino acid substitutions (represented by SEQ ID NOs 755-765) that can promote growth, disease reduction and/or prevention in crops and ornamental plants. For ease of reference, this core domain is represented as the consensus sequence having the SEQ ID NO: 766. The various native and mutant Flg22 polypeptides comprising SEQ ID NOs 754-765 are described along with the consensus sequence in Table 9B, below. Therefore, the polypeptides can further comprise a core sequence. The core sequence can comprise any one of SEQ ID NOs 754-766.
The polypeptide can also comprise any polypeptide comprising any one of SEQ ID NOs 1-753 or 767 to 768 wherein the polypeptide further comprises the core sequence comprising any one of SEQ ID NOs: 754-766. The inclusion of the core sequence in the polypeptide or full-length protein of dissimilar function can increase the bioactive priming activity of the polypeptide.
The polypeptide can include a harpin or harpin-like polypeptide.
The amino acid sequence of the harpin or harpin-like polypeptide can comprise SEQ ID NOs: 587-592 and 594-597 (Tables 10 and 11),
The harpin or harpin-like polypeptides can be derived from Xanthomonas species or diverse bacteria genera including Pantoea sesami, Erwinia genidensis, Pantoea sesami, or Erwinia genidensis
Additional Harpin-like bioactive priming polypeptides can be derived from the full length HpaG-like protein from Xanthamonas citri comprising SEQ ID NO: 593.
Application of HpaG-like polypeptides using the native L-harpin-like sequence (SEQ ID NO: 587) or retro inverso D-harpin-like sequence (SEQ ID NO: 588) bioactive priming polypeptides forms as represented in Tables 10 or 11 are useful to increase growth and immune responses in plants when applied either exogenously or endogenously to a plant or plant part. The retro-inverso HpaG-like (e.g. SEQ ID NO: 588) bioactive priming polypeptide is particularly useful to enhance the activity and stability of the HpaG-like polypeptide when applied to plants grown under or exposed to conditions of abiotic stress. The retro-inverso HpaG-like form can be used to enhance growth and protection responses in plants grown under such environments.
The polypeptide can comprise the PSK polypeptide.
The amino acid sequence of the PSK polypeptide can comprise SEQ ID NOs: 598-599.
Phytosulfokine alpha (PSKα) was originally derived from Arabidopsis thaliana and is a sulfonated bioactive priming polypeptide. The PSKα bioactive priming polypeptide(s) are in Table 11.
PSKα is provided either as a synthetic polypeptide or a natural polypeptide that is expressed in a recombinant microorganism, purified and used in agricultural formulations for applications to plants or plant parts.
Root Hair Promoting polypeptide (RHPP)
The polypeptide can comprise a RHPP
The amino acid sequence of the RHPP can comprise SEQ ID NO: 600-601 and 603-606. For example, the amino acid sequence of the RHPP can comprise SEQ ID NO: 600.
A combination of the polypeptide comprising an RHPP and a polypeptide comprising a flagellin or flagellin associated polypeptide is also provided. The flagellin or flagellin associated polypeptide can comprise any one of SEQ ID NO: 226, 752, and 571. In some instances, the polypeptide comprises an RHPP comprising SEQ ID NO: 600 and a flagellin comprising SEQ ID NO: 226.
The polypeptide can comprise the PSK polypeptide, the RHPP, the harpin or harpin-like polypeptide, or a combination thereof.
Additional RHPP bioactive priming polypeptides can be derived from the full length Kunitz Trypsin Inhibitor protein from Glycine max comprising SEQ ID NO: 602. The RHPP polypeptide can be modified via C-terminal amidation, N-terminal acetylation or other modification. The RHPP bioactive priming polypeptide can be obtained through addition of crude protease digest of kunitz trypsin inhibitor and/or soybean meal.
RHPP originally derived for soybean (Glycine max) can be provided, for example, as a foliar application to produce beneficial phenotypes in corn, soybean and other vegetables.
The polypeptide can include a retro inverso (RI) RHPP.
The retro inverso RHPP can comprise SEQ ID NO& 601, 605 or 606.
The retro inverso (RI) RHPP can be modified via C-terminal amidation or N-terminal acetylation.
The polypeptide can comprise an EF-Tu polypeptide.
Peptides derived from elongation factor Tu (EF-Tu) can be used separately or in combination with the other bioactive priming polypeptides as described herein such as in combination with Flg22 polypeptides to provide multiple modes of defense against pathogenic organisms, generally bacterial and fungal microorganisms but also including other infection agents, such as viruses.
Table 16 provides preferred N-terminal polypeptides derived from various EF-Tu bioactive priming polypeptides selected from both plants and bacteria. The EF-Tu derived polypeptides can be any length from 18 to 26 amino acids or less than 26 amino acids in length. Table 17 further provides retro-inverse (all-D) versions of EF-Tu polypeptides derived from bacteria and algae.
The amino acid sequence of the EF-Tu polypeptide can comprise and one of SEQ ID NOs: 607-640.
The amino acid sequence of the EF-Tu polypeptide can comprise SEQ ID NO: 616 or 617.
The EF-Tu polypeptide can be modified via N-terminal acetylation. For example, the EF-Tu polypeptide can be modified via N-terminal acetylation and comprise any of SEQ ID NOs: 607, 608, 610, 611, 613, 614, 616, 617, 619, or 622.
The polypeptide can comprise the thionin or thionin-like polypeptide.
The thionin or thionin-like polypeptide can be fused to a phloem targeting sequence to form a fused polypeptide, the amino acid sequence of the phloem targeting sequence comprising any one of SEQ ID NOs: 641-649, or any combination thereof, for delivering the fused polypeptide to vascular tissue or cells and/or phloem or phloem-associated tissue or cells in the plant or plant part.
The amino acid sequence of the phloem targeting sequence can comprise SEQ ID NO: 641.
More specifically, targeting sequences useful for targeting AMP polypeptides, such as thionins or Flg polypeptides to the vascular tissues (xylem and phloem) can be extremely useful for treating diseases that colonize restricted tissues involved in the transport of fluids and nutrients (e.g., water soluble nutrients, sugars, amino acids, hormones, etc.). Vascular tissues such as the xylem transport and store water and water-soluble nutrients and the phloem cells transport sugars, proteins, amino acids, hormones and other organic molecules in plants.
Preferred vascular/phloem targeting polypeptides useful for targeting the thionins and flagellin-associated polypeptides as described herein are provided in Table 18.
A synthetic version of a phloem targeting polypeptide (SEQ ID NO: 641) is particularly useful in targeting anti-microbial polypeptides to the phloem sieve tube and companion cells.
Anti-microbial thionin polypeptides are also provided (Table 19) and are utilized with the phloem targeting sequences provided in Table 18 for targeting the thionin sequences into the phloem tissues of citrus as well as other plants.
The amino acid sequence of the thionin or thionin-like polypeptide can comprise an one of SEQ ID NOs: 650-749 such as SEQ ID NO: 651.
The polypeptide can comprise a fusion protein.
Table 20 (SEQ ID NO: 750) describes the sequences used to make a translational fusion using the nucleotide sequence that encodes the synthetic phloem targeting polypeptide (SEQ ID NO: 641) with a synthetic thionin polypeptide (SEQ ID NO: 650). The upper case (not bald) font sequence identifies the phloem targeting sequence, the upper case bald font identifies the fusion of these two peptide sequences (Table 20) that codes for the phloem targeted bioactive priming polypeptide.
In addition, polypeptides can be chemically synthesized with D-amino acids, β2-amino acids, β3-amino acids, homo amino acids, gamma amino acids, peptoids, N-methyl amino acids, and other non-natural amino acid mimics and derivatives.
The polypeptides may be modified by either natural processes, such as posttranslational processing, or by chemical modification techniques that are well known in the art. Modifications can occur anywhere in a polypeptide, including the polypeptide backbone, the amino acid side-chains and the amino or carboxyl termini. The same type of modification may be present in the same or varying degrees at several sites in a polypeptide. Also, a polypeptide may contain many types of modifications.
Peptides may be branched, for example, as a result of ubiquitination, and they may be cyclic, with or without branching. Cyclic, branched, and branched cyclic polypeptides may result from posttranslation natural processes or may be made by synthetic methods.
Modifications include acetylation, acid addition, acylation, ADP-ribosylation, aldehyde addition, alkylamide addition, amidation, amination, biotinylation, carbamate addition, chloromethyl ketone addition, covalent attachment of a nucleotide or nucleotide derivative, cross-linking, cyclization, disulfide bond formation, demethylation, ester addition, formation of covalent cross-links, formation of cysteine-cysteine disulfide bonds, formation of pyroglutamate, formylation, gamma-carboxylation, glycosylation, GPI anchor formation, hydrazide addition, hydroxyamic acid addition, hydroxylation, iodination, lipid addition, methylation, myristoylation, oxidation, PEGylation, proteolytic processing, phosphorylation, prenylation, palmitoylation, addition of a purification tag, pyroglutamyl addition, racemization, selenoylation, sulfonamide addition, sulfation, transfer-RNA mediated addition of amino acids to proteins such as arginylation, ubiquitination, and urea addition. (see, e.g., Creighton et al. (1993) Proteins—Structure and Molecular Properties, 2nd Ed., T. E. Creighton, W. H. Freeman and Company, New York; Johnson, ed. (1983) Posttranslational Covalent Modification Of Proteins, Academic Press, New York; Seifter et al. (1990) Meth. Enzymol., 182: 626-646; Rattan et al. (1992) Ann. N.Y. Acad. Sci., 663: 48-62; and the like).
Using known methods of protein engineering and recombinant DNA technology, variants may be generated to improve or alter the characteristics of the polypeptides described herein. Such variants include deletions, insertions, inversions, repeats, duplications, extensions, and substitutions (e.g., conservative substitutions) selected according to general rules well known in the art so as have little effect on activity.
The polypeptide can comprise an amino acid sequence having at least 70% identity to any one of SEQ ID NOs. 1-768 wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 75% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 80% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 85% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 90% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 95% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 98% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
The polypeptide can comprise an amino acid sequence having at least 99% identity to any one of SEQ ID NOs. 1-768, wherein the polypeptide has bioactive priming activity.
II. Preparation of Bioactive Priming PolypeptidesMethods and approaches are provided for cloning, genetically modifying and expressing the bioactive priming polypeptides (for example, flagellins) and the bioactive priming polypeptides (for example, Bt.4Q7Flg22) using those methods well understood and commonly used by one of ordinary skill in the art. The methods described herein can be used with any of the bioactive priming polypeptides as described herein and therefore include any of the flagellins, flagellin-associated polypeptides, thionins, harpin-like (HpaG-like), EF-Tu, PSKα or RHPP and/or any combinations thereof.
Bioactive priming polypeptides can be provided as a free polypeptide, immobilized on the surface of a particle, or impregnated on or into a matrix. Several expression systems can be used for the production of free polypeptide.
The flagellin-derived full-coding, partial coding (flagellin polypeptides) and flagellin-associated polypeptides can be overexpressed in Bacillus strain, for example, Bacillus thuringiensis strain BT013A, in Bacillus cereus or in Bacillus subtilis. The flagellins and flagellin-derived polypeptides are cloned using an appropriate expression vector to allow for the abundant production of the polypeptide.
For example, in order to facilitate cloning of the target nucleotides that encode the bioactive priming polypeptide(s) as described herein, an E. coli compatible shuttle vector pSUPER was constructed by fusing the pBC plasmid backbone described above with the E. coli pUC57 cloning vector at compatible BamHI restriction endonuclease sites. The resulting, pSUPER vector carries dual selection markers (ampicillin selection in E. coli and tetracycline selection in Bacillus spp). Cloning was performed by PCR amplification of target nucleotides with specific primers synthesized with 15 bp overlapping the pSUPER insertion site. Specific gene encoding polypeptides were fused to the pSUPER vector with In-Fusion HD Cloning Kit (Clontech). Sequence verified pSUPER constructs were amplified using the pBC suitable backbone Reverse and Forward primers. The resulting PCR products were self-ligated to generate the pBC plasmid that was used to transform the B30 donor Bacillus spp. strain. The final construct was verified to be completely intragenic by Sanger sequencing.
The bioactive priming polypeptides/peptides as described herein are produced in large amounts for field and grower applications by using a free expression system that can utilize a Bacillus subtilis and/or Bacillus thuringiensis strain as the designated heterologous expression strain. The base expression plasmid designated pFEe4B consists of an E. coli section (=e) and a Bacillus section (=pFE). The e section was derived from pUC19 and enables selection and amplification of the vector in E. coli for cloning purposes. It comprises the beta-lactamase gene (bla) conferring resistance to beta-lactam antibiotics such as ampicillin and other penicillin derivatives, as well as an E. coli origin of replication allowing vector multiplication. The pFE section provides selection and plasmid amplification in Bacillus spp. and drives expression of the heterologous polypeptide/peptide of interest. As such it contains a gene conferring resistance to tetracycline (tetL), as well as the gene for a replication protein (repU) responsible for amplifying the plasmid in Bacillus spp., both of which were derived from the native Bacillus cereus plasmid pBC16. The expression cassette of pFEe4B contains a secretion signal (amyQ), a cloning site and a terminator (rspD), the former resulting in secretion of the expressed protein/peptide from the host strain cells into the surrounding medium, and the latter preventing transcription beyond the open reading frame of interest. Expression in pFEe4B is driven by a modified autoinducible promoter, which initiates expression once the culture reaches a sufficient optical density. In the pFEe4b expression system, expression is controlled by an IPTG-inducible promoter sequence from Bacillus subtilis. This promoter consists of a modified constitutive promoter combined with the E. coli lac repressor (lacl) and a ribosome binding site. Thus, expression from pFEe4B-encoded polypeptides/peptides depends on the presence of suitable induction agents such as isopropyl beta-D-1-thiogalactopyranoside (IPTG). However other pFe systems useful for expression of the polypeptides as described herein do not rely on such induction systems for their expression. The pFEe4 plasmid further harbors the E. coli lacl gene under control of the Bacillus licheniformis penicillase promoter to prevent expression of polypeptide/peptide as described herein in absence of any induction agent.
Other commercially available expression vectors, for example, any of those derived from Bacillus subtilis, can also be useful. Other expression vectors were selected for producing the recombinant bioactive priming polypeptides due to the following desired criteria: the recombinant microorganism is non-pathogenic and is considered as generally regarded as safe (GRAS) organisms, it has no significant bias in codon usage and it is capable of secreting extracellular proteins directly into the culture medium providing for a cell free version(s) of the bioactive priming polypeptides.
Other expression systems common in the art can be utilized to express bioactive priming polypeptides in a similar manner.
The bioactive priming polypeptides as described herein can be produced and purified either by the use of a protein tag(s) using affinity purification or by using column protease cleavage methods which release the un-tagged polypeptide(s). Methods of using this approach to make free versions of the bioactive priming polypeptides are commonly known and understood by one of ordinary skill in the art.
Protein tags usually comprise a relatively small sequence of amino acids incorporated into a translated polypeptide, basically providing a molecular tether for the bioactive priming polypeptide of interest. They are commonly used to aid in the expression and purification of recombinant polypeptides. The polyhistidine (His) tag was selected for the purposes of affinity purification of the bioactive priming polypeptides as described. A His tag can be fused to either the N- or C-terminus of a polypeptide. His tags are frequently combined with other tags for dual-labeling. Tags for the bioactive priming polypeptides can be useful to affinity purify them. The tags can also be cleaved off of the bioactive priming polypeptides using specific proteases and column-specific protease cleavage methods to release the purified un-tagged bioactive priming polypeptide or full-length precursor protein of interest. These methods are also common and well known to one of ordinary skill in the art. Other tags that can be utilized are known in the art, and include FLAG tags, antibody epitopes, streptavidin/biotin, among other purification tools. Another useful tag is a glutathione S-transferase (GST) tag.
Protein tags can be provided within the plasmid to produce the polypeptide. Ideally, the plasmid comprises, alongside the sequence encoding the polypeptide of interest, a secretion signal (e.g., the amyE or amyQ secretion signal) to promote secretion, and a protein tag (e.g., glutathione S transferase) to enhance the stability of the polypeptide, thereby enhancing production and stability. In preferred cases, the protein tag (e.g., GST) is linked to the polypeptide using a linker sequence comprising a consensus cleavage sequence. This can allow the addition of a targeted kinase that can cleave the tag and release the purified, isolated polypeptide. A suitable consensus cleavage sequence can comprise an enterokinase cleavage sequence (SEQ ID NO: 772), which can be cleaved by simple application of a bovine enterokinase, for example.
Therefore, a method is provided for producing a polypeptide comprising producing a fusion protein comprising any polypeptide described herein and an Enterokinase (EK) cleavage site via fermentation, the EK cleavage site serving to enhance activity and stability of the polypeptide. The fusion protein encoded by the plasmid can further comprise a protein tag (e.g., a poly-histidine (His) tag, a FLAG tag, an antibody epitope, streptavidin/biotin, glutathione S-transferase (GST), or any combination thereof), wherein the enterokinase cleavage site comprises a linking region connecting the polypeptide and the protein tag. The fusion protein can also comprise a secretion signal. The secretion signal can comprise an amyE or amyQ secretion signal (e.g., SEQ ID NO: 769), or it can comprise any one of SEQ ID NOs 563-570 as described above. The polypeptide comprising the enterokinase (EK) cleavage site can be more stable and produced in higher yields using fermentation than a polypeptide lacking the enterokinase (EK) cleavage site. When desired, an enterokinase (e.g., a bovine enterokinase) can be applied to the fusion protein to activate (e.g., isolate) the polypeptide of interest. The enterokinase can be applied on-site to enable maximum stability of the bioactive priming polypeptide prior to administration.
The bioactive priming polypeptides can be provided in a synthetic form using commercially available peptide synthesis technologies to produce high purity polypeptides. Synthetic production of the bioactive priming polypeptides utilizes general solid-phase peptide synthesis methodologies that are well known to one of ordinary skill in the art. Chemical synthesis methodologies include: a stepwise assembly of peptides from amino acid precursors, whereby peptide elongation proceeds via a coupling reaction between amino acids, followed by the removal of a reversible protecting group. Solid phase peptide synthesis is used to add a covalent attachment step that links the nascent peptide chain to an insoluble polymeric support whereby the anchored peptide can be extended by a series of cycles. These extension reactions are driven to completion and then the synthesized polypeptide is removed from the solid support by filtration and washing steps. MS and HPLC analyses are performed after the completion of synthesis and purification.
Any of the bioactive priming polypeptides as described herein for flagellin-associated polypeptides (Tables 1-5), harpin-like (HpaG-like) polypeptides (Table 10 and 11), phytosulfokine (PSKα) polypeptides (Table 12), RHPP (Table 13-15), elongation factor Tu (EF-Tu polypeptides) (Tables 16 and 17), thionin and thionin-like polypeptides (Table 19) can be provided in synthetic forms.
Additionally, such methods can be used for making and using conserved assistance sequences preferably named signature (SEQ ID NOs: 542-548), signal anchor sorting (SEQ ID NOs: 549-562) and secretion (SEQ ID NOs: 563-570) sequences.
Retro inverso can also be made synthetically or chemically manufactured. Synthetic polypeptides produced in the all-D confirmation are prepared by replacing all the L-amino acid residues with their D-enantiomers resulting in a reversed or retro-all-D-isomer Flg polypeptide. Solid phase synthesis is used to prepare the retro-inverso versions of the Flg polypeptide(s). After synthesis and purification of the retro-inverso polypeptide(s), the amino acid composition is confirmed using mass spectrometry of the Flg polypeptide(s). The purity of the retro-inverso polypeptide(s) is then confirmed at a level greater or equal to 95% using HPLC analysis. The retro-inverso versions of the Flg polypeptide(s) are further characterized using HPLC retention time, relative molecular mass and amino acid composition values (IC50 μM). Retro inverso production using recombinant DNA technology generally involves the use of non-ribosomal protein synthesis mechanisms.
Retro-inverso synthetic Flg bioactive priming polypeptides prepared by solid phase synthesis are tested for their capacity to bind to the FLS2 or alternative FLS receptors, for example, FLS3 also found in plants. Competitive ELISA experiments are used to confirm the binding affinities of retro inverso Flg-associated polypeptides to plant FLS receptors.
Recombinant Bacteria that Express Bioactive Priming Polypeptides
A recombinant microorganism that expresses or overexpresses a polypeptide is also provided. The polypeptide comprises the polypeptides as described above for the composition. For example, the polypeptide can comprise: the flagellin or flagellin-associated polypeptide of (a); or the mutant flagellin or flagellin-associated polypeptide of (b); or the mutant flagellin or flagellin-associated polypeptide of (c); or the harpin or harpin-like polypeptide of (g); or the RHPP of (i); or the KTI polypeptide of (j); or the EF-Tu polypeptide of (l); or the fusion polypeptide of (n); or the PSK polypeptide of (o); or the thionin or thionin-like polypeptide of (q).
The polypeptide can be overexpressed by the microorganism. The recombinant microorganism can comprise a microorganism that is capable of making recombinant bioactive priming polypeptides or their precursors in an effective manner. The preferred microorganism would be from the genus Bacillus, a bacterium of the genus Paenibacillus, a fungus of the genus Penicillium, a bacterium of the genus Glomus, a bacterium of the genus Pseudomonas, a bacterium of the genus Arthrobacter, a bacterium of the genus Paracoccus, a bacterium of the genus Rhizobium, a bacterium of the genus Bradyrhizobium, a bacterium of the genus Azospirillum, a bacterium of the genus Enterobacter, a bacterium of the genus Escherichia, or any combination thereof.
The recombinant microorganism can comprise a bacterium of the genus Bacillus, a bacterium of the genus Paenibacillus, or any combination thereof.
For example, the microorganism can comprise Bacillus mycoides, Bacillus pseudomycoides, Bacillus cereus, Bacillus thuringiensis, Bacillus megaterium, Bacillus subtilis, Bacillus firmus, Bacillus aryabhattai, Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus circulans, Bacillus flexus, Bacillus nealsonii, Bacillus pumulis, Paenibacillus genus bacterium or a combination thereof.
Methods and approaches are commonly used by one of ordinary skill in the art to determine and verify the genus and species of the bacteria. A common method provides chromosomal DNA isolated from the bacteria with PCR amplification of the 16s rRNA region using universal primers (ACTCCTACGGGAGGCAGCAGT) and (GGGTTGCGCTCGTTG/AC). The PCR amplicons are then purified and sequenced for correct identification of the appropriate bacterial strain, for example a specific strain in the genera of Bacillus.
Sample protocols are generally known to one in the art for the preparation of chromosomal DNA, transformation of the DNA of genes encoding the polypeptides using a plasmid, producing the polypeptides in a host bacterium, for example, a Bacillus strain.
The Bacillus strains provided can produce any bioactive priming polypeptide as described herein or a combination thereof. For example, the strain can comprise:
(a) Bacillus aryabhattai CAP53 (NRRL No. B-50819),
(b) Bacillus aryabhattai CAP56 (NRRL No. B-50817),
(c) Bacillus flexus BT054 (NRRL No. B-50816),
(d) Paracoccus kondratievae NC35 (NRRL No. B-50820),
(e) Bacillus mycoides BT155 (NRRL No. B-50921),
(f) Enterobacter cloacae CAP12 (NRRL No. B-50822),
(g) Bacillus nealsonii BOBA57 (NRRL No. NRRL B-50821),
(h) Bacillus mycoides EE118 (NRRL No. B-50918),
(i) Bacillus subtilis EE148 (NRRL No. B-50927),
(j) Alcaligenes faecalis EE107 (NRRL No. B-50920),
(k) Bacillus mycoides EE141 (NRRL NO. B-50916),
(l) Bacillus mycoides BT46-3 (NRRL No. B-50922),
(m) Bacillus cereus family member EE128 (NRRL No. B-50917),
(n) Paenibacillus massiliensis BT23 (NRRL No. B-50923),
(o) Bacillus cereus family member EE349 (NRRL No. B-50928),
(p) Bacillus subtilis EE218 (NRRL No. B-50926),
(q) Bacillus megaterium EE281 (NRRL No. B-50925),
(r) Bacillus cereus family member EE-B00377 (NRRL B-67119);
(s) Bacillus pseudomycoides EE-B00366 (NRRL B-67120),
(t) Bacillus mycoides EE-B00363 (NRRL B-67121),
(u) Bacillus pumilus EE-B00143 (NRRL B-67123),
(v) Bacillus thuringiensis EE-B00184 (NRRL B-67122),
(w) Bacillus mycoides EE116 (NRRL No. B-50919),
(x) Bacillus cereus family member EE417 (NRRL No. B-50974),
(y) Bacillus subtilis EE442 (NRRL No. B-50975),
(z) Bacillus subtilis EE443 (NRRL No. B-50976),
(aa) Bacillus cereus family member EE444 (NRRL No. B-50977),
(bb) Bacillus subtilis EE405 (NRRL No. B-50978),
(cc) Bacillus cereus family member EE439 (NRRL No. B-50979),
(dd) Bacillus megaterium EE385 (NRRL No. B-50980),
(ee) Bacillus cereus family member EE387 (NRRL No. B-50981),
(ff) Bacillus circulans EE388 (NRRL No. B-50982),
(gg) Bacillus thuringiensis EE319 (NRRL No. B-50983),
(hh) Bacillus cereus family member EE377 (NRRL No. B-67119),
(ii) Bacillus mycoides EE363 (NRRL No. B-67121),
(jj) Bacillus pseudomycoides EE366 (NRRL No. B-67120);
(kk) Bacillus thuringiensis BT013A (NRRL No. B-50924);
or any combination thereof. Each of these strains has been deposited with the United States Department of Agriculture (USDA) Agricultural Research Service (ARS), having the address 1815 North University Street, Peoria, Ill. 61604 U.S.A., and are identified by the NRRL deposit numbers provided in parentheses. Strains (a)-(d), (f), and (g) were deposited on Mar. 11, 2013. Strains (e), (hHq), (w), and (kk) were deposited on Mar. 10, 2014. Strains (xHff) were deposited on Sep. 10, 2014. Strain (gg) was deposited on Sep. 17, 2014. Strains (rHv), (hh), (ii), and (j) were deposited on Aug. 19, 2015. Bacillus thuringiensis BT013A is also known as Bacillus thuringiensis 4Q7.
The isolation and characterization of these strains are described in the Examples found within International Publication No: WO/2017/161091, incorporated herein by reference in its entirety. For ease of identification of the organism, International Publication No: WO/2017/161091 A1 also provides the partial 16S ribosomal RNA sequences for each of these strains in a sequence list and in Table 17.
Any of the recombinant microorganisms can be used to overexpress a bioactive priming polypeptide as described herein for a flagellin-associated polypeptide (Tables 1-5), a harpin or harpin-like (HpaG-like) polypeptide (Table 10 or 11), a phytosulfokine (PSKα) polypeptide (Table 12), RHPP (Table 13-15), an EF-Tu polypeptide (Table 16-17, and a thionin or thionin-like polypeptide (Table 19).
The recombinant microorganism can comprise a mixture of two or more of any of the recombinant microorganisms described herein.
The recombinant microorganism can be inactivated. Inactivation results in microorganisms that are unable to reproduce. Inactivation of microorganisms can be advantageous, for example because it allows for delivery of the microorganism to a plant or a plant growth medium while reducing or eliminating any detrimental effects that the live microorganism may have on a plant or on the environment. The recombinant microorganism can be inactivated by any physical or chemical means, e.g., by heat treatment, gamma irradiation, x-ray irradiation, UV-A irradiation, UV-B irradiation, or treatment with a solvent such as glutaraldehyde, formaldehyde, hydrogen peroxide, acetic acid, bleach, chloroform, or phenol, or any combination thereof.
III. CompositionsA composition is provided for bioactive priming of a plant or a plant part to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change plant architecture. The composition comprises either the polypeptide as described herein or any combination thereof, and an agrochemical or a carrier; or any combination of the polypeptides as described herein.
The composition can consist essentially of the bioactive priming polypeptides or polypeptides as described herein.
The composition can comprise a majority of the bioactive priming polypeptides with the remainder of the composition being agrochemicals or carriers. More specifically, the composition can comprise from about 0.00001% to about 95% of the polypeptides, from about 0.1 to about 80 wt. % of the agrochemicals, and from about 5 to about 50 wt. % carrier based on the total weight of the composition. Alternatively, the composition can comprise from about 0.01 to about 5 wt. % of the polypeptides, from about 0.2 to about 70 wt. % of the agrochemicals, and from about 10 to about 30 wt. % carrier based on the total weight of the composition, or the composition can comprise from about 0.05 wt. % to about 1 wt. % of the polypeptides, from about 30 to about 60 wt. % of the agrochemicals, and from about 40 to about 69 wt. % carrier based on the total weight of the composition. Alternatively, the composition can comprise any detectable amount of the polypeptides, and from about 0.1 to about 80 wt. % of the agrochemicals and from about 5 to about 50 wt. % of the carrier, based on the total weight of the composition.
The composition can include either an agrochemical or a carrier which is associated with the polypeptide in nature.
The agrochemical can be non-naturally occurring in combination with the polypeptide.
The agrochemical can include, but is not limited to, a preservative, a buffering agent, a wetting agent, a surfactant, a coating agent, a monosaccharide, a polysaccharide, an abrading agent, a pesticide, an insecticide, an herbicide, a nematicide, a bacteriocide, a fungicide, a miticide, a fertilizer, a biostimulant, a colorant, a humectant, an osmoprotectant, an antibiotic, an amino acid, a biological control agent, or a combination thereof.
When the composition includes an amino acid, the amino acid can be provided separately from the amino acids that comprise the polypeptide. For example, an isolated amino acid can be used. Suitable amino acids include any natural or unnatural amino acids. For example, the composition can comprise cysteine.
The agrochemical can comprise an acid such as an acid that is present from chemical synthesis of any polypeptide described herein. For example, hydrochloric acid, acetic acid, or trifluoroacetic acid can be present if the polypeptide is synthesized such as by fermentation.
When the agrochemical is an acid, it can comprise from about 0.001 to about 30 wt. %, from about 0.01 to about 20 wt. %, or from about 0.1 to about 5 wt. % of the total weight of the composition.
Unless otherwise specified, each agrochemical can comprise from about 0.1 to about 60 wt. %, from about 0.5 to about 50 wt. %, or from about 10 to about 30 wt. % of the total weight of the composition.
When the composition includes a preservative, the preservative can comprise those based on dichlorophene and benzylalcohol hemi formal (PROXEL from ICI or ACTICIDE RS from Thor Chemie and KATHON MK from Dow Chemical) and isothiazolinone derivatives such as alkylisothiazolinones and benzisothiazolinones (ACTICIDE MBS from Thor Chemie). As further examples, suitable preservatives include MIT (2-methyl-4-isothiazolin-3-one), BIT (1,2-benzisothiazolin-3-one, which can be obtained from Avecia, Inc. as PROXEL GXL as a solution in sodium hydroxide and dipropylene glycol), 5-chloro-2-(4-chlorobenzyl)-3(2H)-isothiazolone, 5-chloro-2-methyl-2H-isothiazol-3-one, 5-chloro-2-methyl-2H-isothiazol-3-one, 5-chloro-2-methyl-2H-isothiazol-3-one-hydrochloride, 4,5-dichloro-2-cyclohexyl-4-isothiazolin-3-one, 4,5-dichloro-2-octyl-2H-isothiazol-3-one, 2-methyl-2H-isothiazol-3-one, 2-methyl-2H-isothiazol-3-one-calcium chloride complex, 2-octyl-2H-isothiazol-3-one, benzyl alcohol hemiformal, or any combination thereof.
When the composition includes a buffering agent, the buffering agent can comprise potassium, phosphoric acid, a phosphate salt, citric acid, a citrate salt, a sulfate salt, MOPS, or HEPES. The buffering agent can stabilize the polypeptide in the composition.
When the composition includes a wetting agent, the wetting agent can comprise organosilicones, polyoxyethoxylates, polysorbates, polyethyleneglycol and derivatives thereof, ethoxylates, crop oils, and polysaccharides.
When the composition includes a surfactant, the surfactant can comprise a heavy petroleum oil, a heavy petroleum distillate, a polyol fatty acid ester, a polyethoxylated fatty acid ester, an aryl alkyl polyoxyethylene glycol, a polyoxyethylenepolyoxypropylene monobutyl ether, an alkyl amine acetate, an alkyl aryl sulfonate, a polyhydric alcohol, an alkyl phosphate, an alcohol ethoxylate, an alkylphenol ethoxylate, an alkyphenol ethoxylate, an alkoxylated polyol, an alky polyethoxy ether, an alkylpolyoxethylene glycerol, ethoxylated and soybean oil derivatives, an organosilicone-based surfactant or any combination thereof. Surfactants can be included in a range of compositions including those for foliar use.
When the composition includes a coating agent, the coating agent can comprise a tackifier, polymers, filling agents, or bulking agents.
The tackifier can include, but is not limited to, carboxymethylcellulose and natural and synthetic polymers in the form of powders, granules, or latexes, such as gum Arabic, chitin, polyvinyl alcohol and polyvinyl acetate, as well as natural phospholipids, such as cephalins and lecithins, and synthetic phospholipids. Tackifiers include those composed preferably of an adhesive polymer that can be natural or synthetic without phytotoxic effect on the seed to be coated. Additional tackifiers that can be included, either alone or in combination, include, for example, polyesters, polyether esters, polyanhydrides, polyester urethanes, polyester amides; polyvinyl acetates; polyvinyl acetate copolymers; polyvinyl alcohols and tylose; polyvinyl alcohol copolymers; polyvinylpyrolidones; polysaccharides, including starches, modified starches and starch derivatives, dextrins, maltodextrins, alginates, chitosanes and celluloses, cellulose esters, cellulose ethers and cellulose ether esters including ethylcelluloses, methylcelluloses, hydroxymethylcelluloses, hydroxypropylcelluloses and carboxymethylcellulose; fats; oils; proteins, including casein, gelatin and zeins; gum arabics; shellacs; vinylidene chloride and vinylidene chloride copolymers; lignosulfonates, in particular calcium lignosulfonates; polyacrylates, polymethacrylates and acrylic copolymers; polyvinylacrylates; polyethylene oxide; polybutenes, polyisobutenes, polystyrene, polybutadiene, polyethyleneamines, polyethylenamides; acrylamide polymers and copolymers; polyhydroxyethyl acrylate, methylacrylamide monomers; and polychloroprene, or any combination thereof. Tackifiers can be used in a range of compositions including those for seed treatment.
When the composition includes an abrading agent, the abrading agent can comprise talc, graphite, or a combination of both.
A humectant is a hygroscopic substance that assists with the retention of moisture. When the composition includes a humectant, the humectant can comprise: glycerol, glycerin, a glycerol derivative (e.g. glycerol monosterate, glycerol triacetate, triacetin, propylene glycol, hexylene glycol, or butylene glycol), triethylene glycol, tripolypropylene glycol, glyceryl triacetate, sucrose, tagatose, a sugar alcohol or a sugar polyol (e.g glycerol, sorbitol, xylitol, mannitol, or mantitol), a polymeric polyol (e.g. polydextrose, a collagen, an aloe or an aloe vera gel), or an alpha hydroxy acid (e.g. lactic acid, honey, molasses, quillaia, sodium hexametaphosphate, lithium chloride or urea). Synthetic humectants can also comprise: butylene glycol, and tremella extract.
When the composition includes a pesticide, the pesticide can comprise an insecticide, a herbicide, a fungicide, a bacteriocide, a nematicide, a miticide, or any combination thereof.
When the composition includes an insecticide, the insecticide can comprise clothianidin, imidacloprid, an organophosphate, a carbamate, a pyrethroid, an acaricide, an alkyl phthalate, boric acid, a borate, a fluoride, sulfur, a haloaromatic substituted urea, a hydrocarbon ester, a biologically-based insecticide, or any combination thereof. For example, the insecticide can comprise clothianidin or imidacloprid.
The agrochemical can comprise an herbicide. The herbicide can comprise 2,4-D, 2,4-DB, acetochlor, acifluorfen, alachlor, ametryn, atrazine, aminopyralid, benefin, bensulfuron, bensulfuron methyl bensulide, bentazon, bispyribac sodium, bromacil, bromoxynil, butylate, carfentrazone, chlorimuron, 2-chlorophenoxy acetic acid, chlorsulfuron, chlorimuron ethyl, clethodim, clomazone, clopyralid, cloransulam, CMPP-P-DMA, cycloate, DCPA, desmedipham, dicamba, dichlobenil, diclofop, 2,4-dichlorophenol, dichlorophenoxyacetic acid, dichlorprop, dichlorprop-P, diclosulam, diflufenzopyr, dimethenamid, dimethyl amine salt of 2,4-dichlorophenoxyacetic acid, diquat, diuron, DSMA, endothall, EPTC, ethalfluralin, ethofumesate, fenoxaprop, fluazifop-P, flucarbazone, flufenacet, flumetsulam, flumiclorac, flumioxazin, fluometuron, fluroxypyr, fluorxypyr 1-methyleptylester, fomesafen, fomesafen sodium salt, foramsulfuron, glufosinate, glufosinate-ammonium, glyphosate, halosulfuron, halosulfuron-methyl, hexazinone, 2-hydroxyphenoxy acetic acid, 4-hydroxyphenoxy acetic acid, imazamethabenz, imazamox, imazapic, imazaquin, imazethapyr, isoxaben, isoxaflutole, lactofen, linuron, mazapyr, MCPA, MCPB, mecoprop, mecoprop-P, mesotrione, metolachlor-s, metribuzin, metsulfuron, metsulfuron-methyl, molinate, MSMA, napropamide, naptalam, nicosulfuron, norflurazon, oryzalin, oxadiazon, oxyfluorfen, paraquat, pelargonic acid, pendimethalin, phenmedipham, picloram, primisulfuron, prodiamine, prometryn, pronamide, propanil, prosulfuron, pyrazon, pyrithiobac, pyroxasulfone, quinclorac, quizalofop, rimsulfuron, sethoxydim, siduron, simazine, sulfentrazone, sulfometuron, sulfosulfuron, tebuthiuron, terbacil, thiazopyr, thifensulfuron, thifensulfuron-methyl, thiobencarb, tralkoxydim, triallate, triasulfuron, tribenuron, tribemuron-methyl, triclopyr, trifluralin, triflusulfuron, or any combination thereof.
When the composition includes a nematicide, the nematicide can comprise Bacillus firmus, fluopyram, antibiotic nematicides such as abamectin; carbamate nematicides such as acetoprole, Bacillus chitonosporus, chloropicrin, benclothiaz, benomyl, Burholderia cepacia, carbofuran, carbosulfan, and cleothocard; dazomet, DBCP, DCIP, alanycarb, aldicarb, aldoxycarb, oxamyl, diamidafos, fenamiphos, fosthietan, phosphamidon, cadusafos, chlorpyrifos, diclofenthion, dimethoate, ethoprophos, fensulfothion, fostiazate, harpins, heterophos, imicyafos, isamidofos, isazofos, methomyl, mecarphon, Myrothecium verrucaria, Paecilomyces lilacinus, Pasteuria nishizawae (including spores thereof), phorate, phosphocarb, terbufos, thionazin, triazophos, tioxazafen, dazomet, 1,2-dichloropropane, 1,3-dichloropropene, furfural, iodomethane, metam, methyl bromide, methyl isothiocyanate, xylenol, or any combination thereof. For example, the nematicide can comprise Bacillus firmus strain i-2580, Pasteuria nishizawae (including spores thereof), or fluopyram.
When the composition includes a bacteriocide, the bacteriocide can comprise streptomycin, penicillins, tetracyclines, oxytetracycline, kasugamycin, ampicillin, oxolinic acid, chlorotetracycline, copper oxide, or any combination thereof. For example, the bacteriocide can comprise oxytetracycline.
Biological control agents are broadly defined as microorganisms that can be used instead of synthetic pesticides or fertilizers. When the composition includes a biological control agent, the biological control agent can comprise Bacillus thuringiensis, Bacillus megaterium, Bacillus mycoides isolate J, Bacillus methylotrophicus, Bacillus vallismortis, Chromobacterium subtsugae, Deiftia acidovorans, Streptomyces lydicus, Streptomyces colombiensis, Streptomyces galbus K61, Penicillium bilaii, a lipopeptide-producing Bacillus subtilis strain, a lipopeptide-producing Bacillus amyloliquefaciens strain, a Bacillus firmus strain or a Bacillus pumilus strain.
The agrochemical can include a fungicide. The fungicide can comprise aldimorph, ampropylfos, ampropylfos potassium, andoprim, anilazine, azaconazole, azoxystrobin, benalaxyl, benodanil, benomyl, benzamacril, benzamacryl-isobutyl, benzovindflupyr, bialaphos, binapacryl, biphenyl, bitertanol, blasticidin-S, boscalid, bromuconazole, bupirimate, buthiobate, calcium polysulphide, capsimycin, captafol, captan, carbendazim, carvon, quinomethionate, chlobenthiazone, chlorfenazole, chloroneb, chloropicrin, chlorothalonil, chlozolinate, clozylacon, cufraneb, cymoxanil, cyproconazole, cyprodinil, cyprofuram, debacarb, dichlorophen, diclobutrazole, diclofluanid, diclomezine, dicloran, diethofencarb, dimethirimol, dimethomorph, dimoxystrobin, diniconazole, diniconazole-M, dinocap, diphenylamine, dipyrithione, ditalimfos, dithianon, dodemorph, dodine, drazoxolon, edifenphos, epoxiconazole, etaconazole, ethirimol, etridiazole, famoxadon, fenapanil, fenarimol, fenbuconazole, fenfuram, fenitropan, fenpiclonil, fenpropidin, fenpropimorph, fentin acetate, fentin hydroxide, ferbam, ferimzone, fluazinam, fludioxonil, flumetover, fluoromide, fluoxastrobin fluquinconazole, flurprimidol, flusilazole, flusulfamide, flutolanil, flutriafol, folpet, fosetyl-aluminium, fosetyl-sodium, fthalide, fuberidazole, furalaxyl, furametpyr, furcarbonil, furconazole, furconazole-cis, furmecyclox, guazatine, hexachlorobenzene, hexaconazole, hymexazole, imazalil, imibenconazole, iminoctadine, iminoctadine albesilate, iminoctadine triacetate, iodocarb, iprobenfos (IBP), iprodione, irumamycin, isoprothiolane, isovaledione, kasugamycin, kresoxim-methyl, copper preparations, such as: copper hydroxide, copper naphthenate, copper oxychloride, copper sulphate, copper oxide, oxine-copper and Bordeaux mixture, mancopper, mancozeb, maneb, meferimzone, mepanipyrim, mepronil, metconazole, metalzxyl, methasulfocarb, methfuroxam, metiram, metomeclam, metsulfovax, mildiomycin, myclobutanil, myclozolin, nickel dimethyldithiocarbamate, nitrothal-isopropyl, nuarimol, ofurace, oxadixyl, oxamocarb, oxolinic acid, oxycarboxim, oxyfenthiin, paclobutrazole, pefurazoate, penconazole, pencycuron, phosdiphen, picoxystrobin, pimaricin, piperalin, polyoxin, polyoxorim, probenazole, prochloraz, procymidone, propamocarb, propanosine-sodium, propiconazole, propineb, prothiocinazole, pyrazophos, pyrifenox, pyrimethanil, pyroquilon, pyroxyfur, quinconazole, quintozene (PCNB), a strobilurin, sulphur and sulphur preparations, tebuconazole, tecloftalam, tecnazene, tetcyclasis, tetraconazole, thiabendazole, thicyofen, thifluzamide, thiophanate-methyl, tioxymid, tolclofos-methyl, tolylfluanid, triadimefon, triadimenol, triazbutil, a triazole, triazoxide, trichlamide, tricyclazole, triclopyr, tridemorph, trifloxystrobin, triflumizole, triforine, uniconazole, validamycin A, vinclozolin, viniconazole, zarilamide, zineb, ziram and also Dagger G, OK-8705, OK-8801, a-(1,1-dimethylethyl)-(3-(2-phenoxyethyl)-1H-1,2,4-triazole-1-ethanol, a-(2,4-dichlorophenyl)-[3-fluoro-3-propyl-1H-1,2,4-triazole-1-ethanol, a-(2,4-dichlorophenyl)-[3-methoxy-a-methyl-1H-1,2,4-triazole-1-ethanol, a-(5-methyl-1,3-dioxan-5-yl)-[3-[[4-(trifluoromethyl)-phenyl]-methylene]-1H-1,2,4-triazole-1-ethanol, (5RS,6RS)-6-hydroxy-2,2,7,7-tetramethyl-5-(1H-1,2,4-triazol-1-yl)-3-octanone, (E)-a-(methoxyimino)-N-methyl-2-phenoxy-phenylacetamide, 1-isopropyl{2-methyl-1-[[[1-(4-methylphenyl)-ethyl]-amino]-carbonyl]-propyl}carbamate, 1-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-yl)-ethanone-O-(phenyl methyl)-oxime, 1-(2-methyl-1-naphthalenyl)-1H-pyrrole-2,5-dione, 1-(3,5-dichlorophenyl)-3-(2-propenyl)-2,5-pyrrolidindione, 1-[(diiodomethyl)-sulphonyl]-4-methyl-benzene, 1-[2-(2,4-dichlorophenyl)-1, 3-dioxolan-2-yl]-methyl]-1H-imidazole, 1-[[2-(4-chlorophenyl)-3-phenyloxiranyl]-methyl]-1H-1,2,4-triazole, 1-[1-[2-[(2,4-dichlorophenyl)-methoxy]-phenyl]-ethenyl]-1H-imidazole, 1-methyl-5-nonyl-2-(phenylmethyl)-3-pyrrolidinole, 2′,6′-dibromo-2-methyl-4′-trifluoromethoxy-4′-trifluoro-methyl-1, 3-thiazole-carboxanilide, 2,2-dichloro-N-[1-(4-chlorophenyl)-ethyl]-1-ethyl-3-methyl-cyclopropanecarboxamide, 2,6-dichloro-5-(methylthio)-4-pyrimidinyl-thiocyanate, 2,6-dichloro-N-(4-trifluoromethylbenzyl)-benzamide, 2,6-dichloro-N-[[4-(trifluoromethyl)-phenyl]-methyl]-benzamide, 2-(2,3,3-triiodo-2-propenyl)-2H-tetrazole, 2-[(1-methylethyl)-sulphonyl]-5-(trichloromethyl)-1,3,4-thiadiazole, 2-[[6-deoxy-4-O-(4-O-methyl-(3-D-glycopyranosyl)-a-D-glucopyranos yl]-amino]-4-methoxy-1H-pyrrolo [2,3-d]pyrimidine-5-carbonitrile, 2-aminobutane, 2-bromo-2-(bromomethyl)-pentanedinitrile, 2-chloro-N-(2,3-dihydro-1,1,3-trimethyl-1H-inden-4-yl)-3-pyridinecarboxamide, 2-chloro-N-(2,6-dimethylphenyl)-N-(isothiocyanatomethyl)-acetamide, 2-phenylphenol (OPP), 3,4-dichloro-1-[4-(difluoromethoxy)-phenyl]-pyrrole-2,5-dione, 3,5-dichloro-N-[cyano[(1-methyl-2-propynyl)-oxy]-methyl]-benzamide, 3-(1,1-dimethylpropyl-1-oxo-1H-indene-2-carbonitrile, 3-[2-(4-chlorophenyl)-5-ethoxy-3-isoxazolidinyl]-pyridine, 4-chloro-2-cyano-N,N-dimethyl-5-(4-methylphenyl)-1H-imidazole-I-sulphonamide, 4-methyl-tetrazolo[1,5-a]quinazolin-5(4H)-one, 8-(1,1-dimethylethyl)-N-ethyl-N-propyl-1,4-dioxaspiro[4, 5]decane-2-methanamine, 8-hydroxyquinoline sulphate, 9H-xanthene-2-[(phenylamino)-carbonyl]-9-carboxylic hydrazide, bis-(1-methylethyl)-3-methyl-4-[(3-methylbenzoyl)-oxy]-2,5-thiophenedicarboxylate, cis-1-(4-chlorophenyl)-2-(1H-1,2,4-triazol-1-yl)-cycloheptanol, cis-4-[3-[4-(1,1-dimethylpropyl)-phenyl-2-methylpropyl]-2,6-dimethyl-morpholine hydrochloride, ethyl [(4-chlorophenyl)-azo]-cyanoacetate, potassium bicarbonate, methanetetrathiol-sodium salt, methyl 1-(2,3-dihydro-2,2-dimethyl-inden-1-yl)-1H-imidazole-5-carboxylate, methyl N-(2,6-dimethylphenyl)-N-(5-isoxazolylcarbonyl)-DL-alaninate, methyl N-(chloroacetyl)-N-(2,6-dimethylphenyl)-DL-alaninate, N-(2,3-dichloro-4-hydroxyphenyl)-1-methyl-cyclohexanecarboxamide, N-(2,6-dimethyl phenyl)-2-methoxy-N-(tetra hydro-2-oxo-3-furanyl)-acetamide, N-(2,6-dimethyl phenyl)-2-methoxy-N-(tetrahydro-2-oxo-3-thienyl)-acetamide, N-(2-chloro-4-nitrophenyl)-4-methyl-3-nitro-benzenesulphonamide, N-(4-cyclohexylphenyl)-1,4,5,6-tetrahydro-2-pyrimidinamine, N-(4-hexylphenyl)-1,4,5,6-tetrahydro-2-pyrimidinamine, N-(5-chloro-2-methylphenyl)-2-methoxy-N-(2-oxo-3-oxazolidinyl)-acetamide, N-(6-methoxy)-3-pyridinyl)-cyclopropanecarboxamide, N-[2,2,2-trichloro-1-[(chloroacetyl)-amino]-ethyl]-benzamide, N-[3-chloro-4,5-bis(2-propinyloxy)-phenyl]-N′-methoxy-methanimidamide, N-formyl-N-hydroxy-DL-alanine-sodium salt, 0,0-diethyl [2-(dipropylamino)-2-oxoethyl]-ethylphosphoramidothioate, O-methyl S-phenyl phenylpropylphosphoramidothioate, S-methyl 1,2,3-benzothiadiazole-7-carbothioate, and spiro[2H]-1-benzopyrane-2,1′(3′H)-isobenzofuran]-3′-one, N-trichloromethyl)thio-4-cyclohexane-1,2-dicarboximide, tetramethylthioperoxydicarbonic diamide, methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-DL-alaninate, 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1-H-pyrrol-3-carbonitril, or any combination thereof.
When the polypeptides are formulated or applied in combination with commercially available fungicides, the compositions can provide an extra layer of protection for enhancing disease prevention or spread in a plant. The combination of the polypeptides with a fungicide can protect a plant against a primary or secondary fungal infection which may occur if the plant has become compromised or weakened due to exposure to abiotic stress or disease.
The strobilurin fungicide can comprise a Strobilurin A, a Strobilurin B, a Strobilurin C, a Strobilurin D, a Strobilurin E, a Strobilurin F, a Strobilurin G, a Strobilurin H, an Azoxystrobin, a Trifloxystrobin, a Kresoxim methyl, a Fluoxastrobin, Picoxystrobin, or any combination thereof.
The strobilurin fungicide can comprise a non-naturally occurring strobilurin fungicide such as an Azoxystrobin, a Trifloxystrobin, a Kresoxim methyl, a Fluoxastrobin, or any combination thereof. For example, the strobilurin fungicide can comprise a Trifloxystrobin, Fluoxastrobin or Picoxystrobin. Strobilurin fungicides are used to control a range of fungal diseases, including water molds, downy mildews, powdery mildews, leaf spotting and blighting fungi, fruit rotters, and rusts. They are useful for treating a variety of crops, including cereals, field crops, fruits, tree nuts, vegetables, turfgrasses, and ornamentals.
The triazole fungicide can comprise prothioconazole, imidazole, imidazil, prochloraz, propiconazole, triflumizole, diniconazole, flusilazole, penconazole, hexaconazole, cyproconazole, myclobutanil, tebuconazole, difenoconazole, tetraconazole, fenbuconazole, epoxiconazole, metconazole, fluquinconazole, triticonazole, or any combination thereof.
The bioactive priming polypeptides can be delivered in combination with strobilurins and triazole fungicides, especially fluoxastrobin or trifloxystrobin in combination with prothioconazole.
In addition, the fungicide can comprise azoxystrobin, carboxin, difenoconazole, fludioxonil, fluxapyroxad, ipconazole, mefenoxam, pyraclostrobin, silthiofam, sedaxane, thiram, triticonazole or any combination thereof.
In addition to foliar applied fungicides as described herein, the bioactive priming polypeptides can be provided in combination with a fungicide, an insecticide, a nematicide, a bacteriocide, and a miticide or any agrochemical which is a biological agent.
The agrochemical can include a fertilizer. The fertilizer can comprise ammonium sulfate, ammonium nitrate, ammonium sulfate nitrate, ammonium chloride, ammonium bisulfate, ammonium polysulfide, ammonium thiosulfate, aqueous ammonia, anhydrous ammonia, ammonium polyphosphate, aluminum sulfate, calcium nitrate, calcium ammonium nitrate, calcium sulfate, calcined magnesite, calcitic limestone, calcium oxide, calcium nitrate, dolomitic limestone, hydrated lime, calcium carbonate, diammonium phosphate, monoammonium phosphate, magnesium nitrate, magnesium sulfate, potassium nitrate, potassium chloride, potassium magnesium sulfate, potassium sulfate, sodium nitrates, magnesian limestone, magnesia, urea, urea-formaldehydes, urea ammonium nitrate, sulfur-coated urea, polymer-coated urea, isobutylidene diurea, K2SO4-Mg2SO4, kainite, sylvinite, kieserite, Epsom salts, elemental sulfur, marl, ground oyster shells, fish meal, oil cakes, fish manure, blood meal, rock phosphate, super phosphates, slag, bone meal, wood ash, manure, bat guano, peat moss, compost, green sand, cottonseed meal, feather meal, crab meal, fish emulsion, humic acid, or any combination thereof.
The fertilizer can comprise a liquid fertilizer or a dry fertilizer.
The agrochemical can comprise a micronutrient fertilizer material, the micronutrient fertilizer material comprising boric acid, a borate, a boron frit, copper sulfate, a copper frit, a copper chelate, a sodium tetraborate decahydrate, an iron sulfate, an iron oxide, iron ammonium sulfate, an iron frit, an iron chelate, a manganese sulfate, a manganese oxide, a manganese chelate, a manganese chloride, a manganese frit, a sodium molybdate, molybdic acid, a zinc sulfate, a zinc oxide, a zinc carbonate, a zinc frit, zinc phosphate, a zinc chelate, or any combination thereof.
The agrochemical can comprise an insecticide, the insecticide comprising an organophosphate, a carbamate, a pyrethroid, an acaricide, an alkyl phthalate, boric acid, a borate, a fluoride, sulfur, a haloaromatic substituted urea, a hydrocarbon ester, a biologically-based insecticide, or any combination thereof.
When the composition includes a biostimulant, the biostimulant can comprise a seaweed extract, an elicitor, a polysaccharide, a monosaccharide, a protein extract, a soybean extract, a humic acid, a plant hormone, a plant growth regulator, or any combination thereof.
A variety of colorants may be employed, including organic chromophores classified as nitroso, nitro, azo, including monoazo, bisazo, and polyazo, diphenylmethane, triarylmethane, xanthene, methane, acridine, thiazole, thiazine, indamine, indophenol, azine, oxazine, anthraquinone, phthalocyanine, or any combination thereof.
The composition can further comprise a carrier.
The carrier of the composition can include, but is not limited to, water, peat, wheat, bran, vermiculite, clay, pasteurized soil, calcium carbonate, calcium bicarbonate, dolomite, gypsum, bentonite, a clay, a rock phosphate, a phosphorous compound, titanium dioxide, humus, talc, alginate, activated charcoal, or a combination thereof.
The composition can be in the form of an aqueous solution, a slurry or dispersion, an emulsion, a solid such as a powder or granule, or any other desirable form for applying the composition to a plant or plant part.
Bioactive priming polypeptides such as the flagellin and flagellin-associated polypeptides, thionin (defensin family), harpin-like HpaG, EF-Tu or other growth promoting or altering bioactive priming polypeptides such as PSKα and RHPP can be provided as compositions that can either be exogenously and/or endogenously applied to a plant or a plant part and provide enhanced plant growth, productivity and enhanced health of that plant or plant part as described in more detail below.
The bioactive priming polypeptides can be added separately or in combination as a composition that are useful as applications to provide a benefit to plants and/or plant parts.
In combination, the polypeptides may be formulated and delivered in a purified polypeptide form either as a genetic fusion on the same recombinant vector, or separately using different recombinant vectors.
The bioactive priming polypeptides can also be created and delivered to a plant or plant part as polypeptides from multiple actives in a fusion protein. Examples of this include delivery of multiple flagellin associated polypeptides produced in series with protease cleavage sites between each polypeptide as is within the skill of one of ordinary skill in the art. Such fusion proteins can include any combination of the bioactive priming polypeptides as described herein, including bioactive priming polypeptides from different classes, such as combinations of flagellin associated polypeptides with RHPP. Bioactive priming polypeptides can also be utilized as protein fusions to plant binding domains, which can direct the polypeptides to distinct locations within the plant where they are most desired or needed for their activities to be beneficial.
Additionally, the polypeptides may be added to formulations provided in a synthetic compound form.
The flagellin and flagellin-associated bioactive priming polypeptides as described herein can be provided individually or in combination containing at least two to multiple bioactive priming polypeptides to provide a composition that meets the specific needs of a plant over a wide range of desired host responses and cropping systems.
When a composition includes the retro-inverso form of a Flg bioactive priming polypeptide (for example, RI Bt.4Q7 Flg 22 (SEQ ID NO: 376), the polypeptide exhibits enhanced stability and less degradation over time providing for more activity at the plant cell membrane surface, which enhances the ability of the polypeptide to bind to the receptor and be taken into the plant. Retro inverso forms of such Flg-associated bioactive priming polypeptides are used to provide enhanced stability of the agriculturally applied formulation whereby the Flg polypeptide(s) exhibits enhanced protection from proteolytic cleavage, which contributes to an overall greater activity and shelf life of the composition.
When the polypeptide comprises an RHPP polypeptide, the composition can further comprise a flagellin or flagellin associated polypeptide. The RHPP polypeptide can comprise SEQ ID NO: 600. The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 1-525, 532, 534, 536, 538, 540, 571-586, and 751-752, or any combination thereof. For example, the flagellin or flagellin associated polypeptide can comprise any one of SEQ ID NO: 226, 571, and 752. In some instances, the RHPP polypeptide can comprise SEQ ID NO: 600 and the flagellin or flagellin associated polypeptide can comprise SEQ ID NO: 226.
The polypeptides can be formulated in combination with an assistance polypeptide. The signature (SEQ ID NOs: 542-548), signal anchor sorting (SEQ ID NOs: 549-562) and secretion (SEQ ID NOs: 563-570) polypeptides can be combined with the bioactive priming polypeptides as described for targeting the polypeptides/peptides (Tables 1-5) to the plant cell membrane surface for improved binding and activation of the Flg-associated receptors. This means for efficient delivery and binding of the polypeptide to a plant provides growth promoting benefits, as well as enhanced protection to the plant or plant part.
For example, the harpin or HpaG-like bioactive priming polypeptides as described herein can be used in combination with the assistance polypeptides as described in Tables 6-8), signature polypeptides (SEQ ID NO: 542-548), signal anchor sorting (SEQ ID NO: 549-562) and/or secretion (SEQ ID NO: 563-570) polypeptides. These assistance polypeptides used in combination with the HpaG-like bioactive priming polypeptides are useful to target and deliver the harpin-like bioactive priming polypeptides to the plant cell membrane surface enhancing the contact with the plant cell membrane and provide a conduit facilitating efficient contact and entry of harpin-like (HpaG-like) into the plant or to the plant cell milieu (apoplast).
One or more of the EF-Tu polypeptides can be combined, optionally, with the flagellin or flagellin-associated polypeptide. The amino acid sequence of the EF-Tu polypeptide or polypeptides can comprise SEQ ID NOs: 616 and/or 617. The amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 1-525, 532, 534, 536, 538, 540, 571-586, and 751-753 or any combination thereof. For example, the amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise SEQ ID NO: 571. As another example, the composition can comprise an EF-Tu polypeptides comprising SEQ ID NOs: 616 and 617, and a flagellin or flagellin associated polypeptide comprising SEQ ID NO: 226, 571, 572, or combinations thereof. As another example, the EF-Tu polypeptide or polypeptides having SEQ ID NOs 616 and/or 617 can be combined with a flagellin or flagellin associated polypeptide having SEQ ID NO: 226. Alternatively, the composition can comprise one or more EF-Tu polypeptides alone (e.g., comprising SEQ ID NOs 616 and/or 617). The EF-Tu polypeptides (e.g., SEQ ID Nos 616 and 617) can be further modified via N-terminal acetylation.
Additionally, the EF-Tu polypeptide or the EF-Tu polypeptide and the flagellin or flagellin-associated polypeptide can be combined with the harpin or harpin-like polypeptide. For example, the amino acid sequence of the harpin or harpin-like polypeptide can comprise SEQ ID NO: 587.
The composition can comprise any one of the following combinations: (a) the flagellin or flagellin-associated polypeptides and the amino acid sequences of the flagellin or flagellin-associated polypeptides comprise SEQ ID NOs: 571, 295, 300, 293, and 580; or 295, 300, 293, and 580; or 571, 295, 293, and 580; or 571, 300, 293, and 580; or 571, 293 and 580; or 571, 295, 293; or (b) the flagellin or flagellin-associated polypeptide and the amino acid sequence of the flagellin or flagellin-associated polypeptide comprises SEQ ID NO: 226 and cellobiose, cellulose, chitin, chitosan or any combination thereof; or (c) the flagellin or flagellin-associated polypeptide and the amino acid sequence of the flagellin or flagellin-associated polypeptide comprises SEQ ID NO: 226 and the harpin or harpin-like polypeptide and the amino acid sequence of the harpin or harpin-like polypeptide comprises SEQ ID NO: 591; or (d) the harpin or harpin-like polypeptide and the amino acid sequence of the harpin or harpin-like polypeptide comprises SEQ ID NO: 587 and the PSK polypeptide and the amino acid sequence of the PSK polypeptide comprises SEQ ID NO: 598; or (e) the flagellin or flagellin-associated polypeptide and the amino acid sequence of the flagellin or flagellin-associated polypeptide comprises SEQ ID NO: 226, 752, or 571 or any combination thereof and the EF-Tu polypeptides and the amino acid sequences of the EF-Tu polypeptides comprise SEQ ID NOs: 616 and 617; or (f) the flagellin or flagellin-associated polypeptide and the amino acid sequence of the flagellin or flagellin-associated polypeptide comprises SEQ ID NO: 226, 540, 752, or 571 or any combination thereof; or (g) the RHPP polypeptide and the amino acid sequence of the RHPP polypeptide comprises SEQ ID NO: 600; or (h) the flagellin or flagellin-associated polypeptide and the amino acid sequences of the flagellin or flagellin-associated polypeptide comprises SEQ ID NO: 226, 540, 226, 752, or 571 or any combination thereof and the RHPP polypeptide and the amino acid sequence of the RHPP polypeptide comprises SEQ ID NO: 600; or (i) the flagellin or flagellin-associated polypeptide and the amino acid sequence of the flagellin or flagellin-associated polypeptide comprises SEQ ID NO: 226 and the RHPP polypeptide and the amino acid sequence of the RHPP polypeptide comprises SEQ ID NO: 600.
IV. ApplicationsThe agricultural composition and methods described herein can be used with any species of plant and/or the seeds thereof. The compositions and methods are typically used with seeds that are agronomically important.
The seed can be a transgenic seed from which a transgenic plant can grow that incorporates a transgenic event that confers, for example, tolerance to a particular herbicide or combination of herbicides, increased disease resistance, enhanced tolerance to insects, drought, stress and/or enhanced yield.
The seed can comprise a breeding trait, including for example, a disease tolerant breeding trait.
In some instances, the seed includes at least one transgenic trait and at least one breeding trait.
The bioactive priming polypeptide compositions and methods for applying the polypeptides can be used for the treatment of any suitable seed type, including, but not limited to, row crops and vegetables. For example, one or more plants or plant parts or the seeds of one or more plants can comprise abaca (manila hemp) (Musa textilis), alfalfa for fodder (Medicago sativa), alfalfa for seed (Medicago sativa), almond (Prunus dulcis), anise seeds (Pimpinella anisum), apple (Malus sylvestris), apricot (Prunus armeniaca), areca (betel nut) (Areca catechu), arracha (Arracacia xanthorrhiza), arrowroot (Maranta arundinacea), artichoke (Cynara scolymus), asparagus (Asparagus officinalis), avocado (Persea americana), bajra (pearl millet) (Pennisetum americanum), bambara groundnut (Vigna subterranea), banana (Musa paradisiaca), barley (Hordeum vulgare), beans, dry, edible, for grains (Phaseolus vulgaris), beans, harvested green (Phaseolus and Vigna spp.), beet, fodder (mangel) (Beta vulgaris), beet, red (Beta vulgaris), beet, sugar (Beta vulgaris), beet, sugar for fodder (Beta vulgaris), beet, sugar for seeds (Beta vulgaris), bergamot (Citrus bergamia), betel nut (Areca catechu), black pepper (Piper nigrum), black wattle (Acacia mearnsii), blackberries of various species (Rubus spp.), blueberry (Vaccinium spp.), Brazil nut (Bertholletia excelsa), breadfruit (Artocarpus altilis), broad bean, dry (Vicia faba), broad bean, harvested green (Vicia faba), broccoli (Brassica oleracea var. botrytis), broom millet (Sorghum bicolor), broom sorghum (Sorghum bicolor), Brussels sprouts (Brassica oleracea var. gemmifera), buckwheat (Fagopyrum esculentum), cabbage, red, white, Savoy (Brassica oleracea var. capitata), cabbage, Chinese (Brassica chinensis), cabbage, for fodder (Brassica spp.), cacao (cocoa) (Theobroma cacao), cantaloupe (Cucumis melo), caraway seeds (Carum carvi), cardamom (Elettaria cardamomum), cardoon (Cynara cardunculus), carob (Ceratonia siliqua), carrot, edible (Daucus carota spp. sativa), carrot, for fodder (Daucus carota sativa), cashew nuts (Anacardium occidentale), cassava (manioc) (Manihot esculenta), castor bean (Ricinus communis), cauliflower (Brassica oleracea var. botrytis), celeriac (Apium graveolens var. rapaceum), celery (Apium graveolens), chayote (Sechium edule), cherry, all varieties (Prunus spp.), chestnut (Castanea sativa), chickpea (gram pea) (Cicer arietinum), chicory (Cichorium intybus), chicory for greens (Cichoium intybus), chili, dry (all varieties) (Capsicum spp. (annuum)), chili, fresh (all varieties) (Capsicum spp. (annuum)), cinnamon (Cinnamomum verum), citron (Citrus medica), citronella (Cymbopogon citrates; Cymbopogon nardus), clementine (Citrus reticulata), clove (Eugenia aromatica; Syzygium aromaticum), clover for fodder (all varieties) (Trifolium spp.), clover for seed (all varieties) (Trifolium spp.), cocoa (cacao) (Theobroma cacao), coconut (Cocos nucifera), cocoyam (Colocasia esculenta), coffee (Coffea spp.), cola nut, all varieties (Cola acuminata), colza (rapeseed) (Brassica napus), corn (maize), for cereals (Zea mays), corn (maize), for silage (Zea mays), corn (maize), for vegetable (Zea mays), corn for salad (Valerianella locusta), cotton, all varieties (Gossypium spp.), cottonseed, all varieties (Gossypium spp.), cowpea, for grain (Vigna unguiculata), cowpea, harvested green (Vigna unguiculata), cranberry (Vaccinium spp.), cress (Lepidium sativum), cucumber (Cucumis sativus), currants, all varieties (Ribes spp.), custard apple (Annona reticulate), dasheen (Colocasia esculenta), dates (Phoenix dactylifera), drumstick tree (Moringa oleifera), durra (sorghum) (Sorghum bicolour), durum wheat (Triticum durum), earth pea (Vigna subterranea), edo (eddoe) (Xanthosoma spp.; Colocasia spp.), eggplant (Solanum melongena), endive (Cichorium endivia), fennel (Foeniculum vulgare), fenugreek (Trigonella foenum-graecum), fig (Ficus carica), filbert (hazelnut) (Corylus avellana), fique (Furcraea macrophylla), flax for fiber (Linum usitatissimum), flax for oil seed (linseed) (Linum usitatissimum), formio (New Zealand flax) (Phormium tenax), garlic, dry (Allium sativum), garlic, green (Allium sativum), geranium (Pelargonium spp.; Geranium spp.), ginger (Zingiber officinale), gooseberry, all varieties (Ribes spp.), gourd (Lagenaria spp; Cucurbita spp.), gram pea (chickpea) (Cicer arietinum), grape (Vitis vinifera), grapefruit (Citrus paradisi), grapes for raisins (Vitis vinifera), grapes for table use (Vitis vinifera), grapes for wine (Vitis vinifera), grass esparto (Lygeum spartum), grass, orchard (Dactylis glomerata), grass, Sudan (Sorghum bicolor var. sudanense), groundnut (peanut) (Arachis hypogaea), guava (Psidium guajava), guinea corn (sorghum) (Sorghum bicolor), hazelnut (filbert) (Corylus avellana), hemp fiber (Cannabis sativa spp. indica), hemp, manila (abaca) (Musa textilis), hemp, sun (Crotalaria juncea), hempseed (marijuana) (Cannabis sativa), henequen (Agave fourcroydes), henna (Lawsonia inermis), hop (Humulus lupulus), horse bean (Vicia faba), horseradish (Armoracia rusticana), hybrid maize (Zea mays), indigo (Indigofera tinctoria), jasmine (Jasminum spp.), Jerusalem artichoke (Helianthus tuberosus), jowar (sorghum) (Sorghum bicolor), jute (Corchorus spp.), kale (Brassica oleracea var. acephala), kapok (Ceiba pentandra), kenaf (Hibiscus cannabinus), kohlrabi (Brassica oleracea var. gongylodes), lavender (Lavandula spp.), leek (Allium ampeloprasum; Allium porrum), lemon (Citrus limon), lemongrass (Cymbopogon citratus), lentil (Lens culinaris), lespedeza, all varieties (Lespedeza spp.), lettuce (Lactuca sativa var. capitata), lime, sour (Citrus aurantifolia), lime, sweet (Citrus limetta), linseed (flax for oil seed) (Linum usitatissimum), licorice (Glycyrrhiza glabra), litchi (Litchi chinensis), loquat (Erobotrya japonica), lupine, all varieties (Lupinus spp.), Macadamia (Queensland nut) (Macadamia spp. ternifolia), mace (Myristica fragrans), maguey (Agave atrovirens), maize (corn) (Zea mays), maize (corn) for silage (Zea mays), maize (hybrid) (Zea mays), maize, ordinary (Zea mays), mandarin (Citrus reticulata), mangel (fodder beet) (Beta vulgaris), mango (Mangifera indica), manioc (cassava) (Manihot esculenta), maslin (mixed cereals) (mixture of Triticum spp. and Secale cereale), medlar (Mespilus germanica), melon, except watermelon (Cucumis melo), millet broom (Sorghum bicolor), millet, bajra (Pennisetum americanum), millet, bulrush (Pennisetum americanum), millet, finger (Eleusine coracana), millet, foxtail (Setaria italica), millet, Japanese (Echinochloa esculenta), millet, pearl (bajra, bulrush) (Pennisetum americanum), millet, proso (Panicum miliaceum), mint, all varieties (Mentha spp.), mulberry for fruit, all varieties (Morus spp.), mulberry for silkworms (Morus alba), mushrooms (Agaricus spp.; Pleurotus spp.; Volvariella), mustard (Brassica nigra; Sinapis alba), nectarine (Prunus persica var. nectarina), New Zealand flax (formio) (Phormium tenax), Niger seed (Guizotia abyssinica), nutmeg (Myristica fragrans), oats, for fodder (Avena spp.), oil palm (Elaeis guineensis), okra (Abelmoschus esculentus), olive (Olea europaea), onion seed (Allium cepa), onion, dry (Allium cepa), onion, green (Allium cepa), opium (Papaver somniferum), orange (Citrus sinensis), orange, bitter (Citrus aurantium), ornamental plants (various), palm palmyra (Borassus flabellifer), palm, kernel oil (Elaeis guineensis), palm, oil (Elaeis guineensis), palm, sago (Metroxylon sagu), papaya (pawpaw) (Carica papaya), parsnip (Pastinaca sativa), pea, edible dry, for grain (Pisum sativum), pea, harvested green (Pisum sativum), peach (Prunus persica), peanut (groundnut) (Arachis hypogaea), pear (Pyrus communis), pecan nut (Carya illinoensis), pepper, black (Piper nigrum), pepper, dry (Capsicum spp.), persimmon (Diospyros kaki; Diospyros virginiana), pigeon pea (Cajanus cajan), pineapple (Ananas comosus), pistachio nut (Pistacia vera), plantain (Musa sapientum), plum (Prunus domestica), pomegranate (Punica granatum), pomelo (Citrus grandis), poppy seed (Papaver somniferum), potato (Solamum tuberosum), palm, kernel oil (Elaeis guineensis), potato, sweet (Ipomoea batatas), prune (Prunus domestica), pumpkin, edible (Cucurbita spp.), pumpkin, for fodder (Cucurbita spp.), pyrethum (Chrysanthemum cineraraefolium), quebracho (Aspidosperma spp.), Queensland nut (Macadamia spp. temifolia), quince (Cydonia oblonga), quinine (Cinchona spp.), quinoa (Chenopodium quinoa), ramie (Boehmeria nivea), rapeseed (colza) (Brassica napus), raspberry, all varieties (Rubus spp.), red beet (Beta vulgaris), redtop (Agrostis spp.), rhea (Boehmeria nivea), rhubarb (Rheum spp.), rice (Oryza sativa; Oryza glaberima), rose (Rose spp.), rubber (Hevea brasiliensis), rutabaga (swede) (Brassica napus var. napobrassica), rye (Secale cereale), ryegrass seed (Lolium spp.), safflower (Carthamus tinctorius), sainfoin (Onobrychis viciifolia), salsify (Tragopogon porrifolius), sapodilla (Achras sapota), satsuma (mandarin/tangerne) (Citrus reticulata), scorzonera (black salsify) (Scorzonera hispanica), sesame (Sesamum indicum), shea butter (nut) (Vitellaria paradoxa), sisal (Agave sisalana), sorghum (Sorghum bicolor), sorghum, broom (Sorghum bicolor), sorghum, durra (Sorghum bicolor), sorghum, guinea corn (Sorghum bicolor), sorghum, jowar (Sorghum bicolor), sorghum, sweet (Sorghum bicolor), soybean (Glycine max), soybean hay (Glycine max), spelt wheat (Triticum spelta), spinach (Spinacia oleracea), squash (Cucurbita spp.), strawberry (Fragaria spp.), sugar beet (Beta vulgaris), sugar beet for fodder (Beta vulgaris), sugar beet for seed (Beta vulgaris), sugarcane for fodder (Saccharum officinarum), sugarcane for sugar or alcohol (Saccharum officinarum), sugarcane for thatching (Saccharum officinarum), sunflower for fodder (Helianthus annuus), sunflower for oil seed (Helianthus annuus), sunhemp (Crotalaria juncea), swede (Brassica napus var. napobrassica), swede for fodder (Brassica napus var. napobrassica), sweet corn (Zea mays), sweet lime (Citrus limetta), sweet pepper (Capsicum annuum), sweet potato (Lopmoea batatas), sweet sorghum (Sorghum bicolor), tangerine (Citrus reticulata), tannia (Xanthosoma sagittifolium), tapioca (cassava) (Manihot esculenta), taro (Colocasia esculenta), tea (Camellia sinensis), teff (Eragrostis abyssinica), timothy (Phleum pratense), tobacco (Nicotiana tabacum), tomato (Lycopersicon esculentum), trefoil (Lotus spp.), triticale, for fodder (hybrid of Triticum aestivum and Secale cereale), tung tree (Aleurites spp.; Fordii), turnip, edible (Brassica rapa), turnip, for fodder (Brassica rapa), urena (Congo jute) (Urena lobata), vanilla (Vanilla planifolia), vetch, for grain (Vicia sativa), walnut (Juglans spp., especially Juglans regia), watermelon (Citrullus lanatus), wheat (Triticum aestivum), yam (Dioscorea spp.), or yerba mate (Ilex paraguarensis).
The compositions and methods disclosed herein can also be applied to turf grass, ornamental grass, flowers, ornamentals, trees, and shrubs.
The compositions comprising the bioactive priming polypeptides are also suitable for use in the nursery, lawn and garden, floriculture or the cut flower industry and provide benefits for enhanced plant productivity, protection health, vigor and longevity. For example, they can be applied to perennials, annuals, forced bulbs, or pseudo bulbs, herbs, groundcovers, trees, shrubs, ornamentals (e.g., orchids, etc.), tropicals, and nursery stock.
The compositions comprising the bioactive priming polypeptides are suitable for treating plants, plant parts and plant propagation material(s), for example, any plant or plant part, such as seeds, roots, stems, floral organs, root stocks, scions, bulb, pseudobulbs, rhizomes, tubers, etc.
The bioactive priming polypeptides can be applied as seed treatments to treat for a number of pests, diseases, nutrient deficiencies while enhancing plant growth and productivity.
Seed coating or dressing compositions can be, for example, a liquid carrier composition, a slurry composition, or a powder composition applied with conventional additives that are provided to make the seed treatment have sticky qualities to stick to and coat the seeds. Suitable additives for a seed composition comprise: talcs, graphites, gums, stabilizing polymers, coating polymers, finishing polymers, slip agents for seed flow and plantability, cosmetic agents and cellulosic materials such as carboxymethyl cellulose and the like. The bioactive priming polypeptide seed treatments can further comprise colorant agents and other such additives.
The bioactive priming polypeptides can be applied individually as seed treatments or in combination with other additives such as fungicides, insecticides, inoculants, plant growth regulators, plant growth promoting microbes, fertilizers and fertilizer enhancers, seed nutrients, biological control agents, herbicidal antidotes and seedling disease treatments and with other conventional seed treatments.
The seed treatment composition as described herein can be applied to seeds in a suitable carrier such as water or a powder that is not harmful to the seeds or the environment. The seeds are then planted in conventional fashion.
Preferred seed treatments such as Bt.4Q7Flg22 (SEQ ID NO: 226 or SEQ ID NO: 571), Ec.Flg22 (SEQ ID NO: 526) and Gm.RHPP (SEQ ID NO: 600) are useful to enhance seedling development, decrease the time for germination, increase the number of seeds that germinate, and enhance seedling survivability. In addition, the seed treatment compositions enhance seed protection from microbial-based diseases which are known to contact the seed or the soil surrounding the seed and spread during early seedling establishment.
The seed treatment composition can comprise a polypeptide as described herein and a fungicide, an insecticide, a nematacide, a biological control agent, a biostimulant, a microbe, or any combination thereof.
The seed treatment composition can comprise a polypeptide as described herein and clothianidin, Bacillus firmus, metalaxyl, or any combination thereof.
The seed treatment composition can comprise a polypeptide as described herein, clothianidin and fluopyram.
The seed treatment can comprise a polypeptide as described herein, metalaxyl and fluopyram.
The bioactive priming polypeptides can be applied directly to the seed as a solution or in combination with other commercially available additives. Solutions containing the water-soluble polypeptide can be sprayed or otherwise applied to the seed as a seed slurry or a seed soak. Solids or dry materials containing soluble bioactive priming polypeptides are also useful to promote effective seedling germination, growth and protection during early seedling establishment.
The bioactive priming polypeptides can be formulated with a solubilizing carrier such as water, buffer (e.g., citrate or phosphate buffer) and other treating agents (i.e., alcohol, other solvents) or any solubilizing agent. In addition, small amounts of drying agent enhancers, such as lower alcohols, etc. can be utilized in the composition. Surfactants, emulsifiers and preservatives can also be added at small (0.5% v/v or less) levels in order to enhance the stability of the seed coating product.
Seed treatments containing the bioactive priming polypeptides can be applied using any commercially available seed treatment machinery or can also be applied using any acceptable non-commercial method(s) such as the use of syringes or any other seed treatment device. General seed treatments coating procedures using bioactive priming polypeptides can be performed using a Wintersteiger HEGE 11 (Wintersteiger AG, Austria, Germany) and applied to the seed of major crops, namely corn, soybean, wheat, rice and various vegetables. The capacity of this seed treatment machinery can accommodate a large number of different seed types, sizes and amounts of seed (20-3000 grams). The seed is loaded into bowls of the seed treater machinery. The bowl selection depends on the treatment seed amount required and the size of the bowl selected: large 14.5 L bowl (500-3000 g seed per coating); medium 7 L bowl (80-800 g seed per coating); and small 1 L bowl (20-100 g seed per coating). Other larger seed treatment systems are also available.
The seed is distributed toward the radial peripheries of the rotatable bowls via an application of centrifugal force with the centrifugal coating device. The spinning disc located at the bottom of the bowl distributes the seed treatment evenly over the seed. At this point, the spin cycle is started which causes the seeds to revolve around the bowl center in a circle to evenly coat the seeds. The process of seed treatment coating is initiated after the seed is evenly dispersed around the spreader. Seed treatment sample material (such as a powdered, semi-liquid, liquid or a slurry) can be applied onto the rotatable disk as the disks are spinning within the rotatable bowls used to distribute the seed treatment evenly to provide a uniform coat and dress the surface of the seed.
A constant air flow delivered using compressed air (2-6 bars) can be provided during seed coating to assist with uniformly coating the seeds in the bowl. The amount of time for the coating of the seed depends on the amount of the seed, the viscosity of the seed treatment and the type of the seed used in the treatment. A seed treatment calculator is used to adjust for all volumes, for most major and commercially grown crops and the type of seed treatment being applied.
The seeds can be coated using a variety of methods including, but not limited to, pouring or pumping, drizzling or spraying an aqueous solution containing the bioactive priming polypeptides on or over a seed, spraying or applying onto a layer of seeds either with the use or without the use of a conveyor system. Suitable mixing devices include tumblers, mixing basins or drums, or other fluid applicating devices that include basins or drums used to contain the seed while coating.
After the seed has been treated and dried, the seeds are distributed into a larger storage container(s). Seeds are either air dried or dried with a continuous air stream that passes over the seeds. Seeds are then transferred into a separate container or bag for shipment, transfer or storage.
The bioactive priming polypeptides can further be provided for delivery to a plant surface or plant plasma membrane as a foliar spray or a seed treatment to an area surrounding a plant or a plant part.
The bioactive priming polypeptide formulation(s) can also be provided as a seed treatment application or on a matrix such as immobilized or impregnated on a particle, or a granule such as used in a broadcast treatment.
The bioactive priming polypeptides as described herein can be applied to plants and plant parts using an exogenous application as a spray, soil treatment, in furrow, seed treatment, dip or wash or as an endogenous application as an injection, inoculation, irrigation, infiltration, etc.
The polypeptides can be applied directly to a plant or to the area surrounding a plant or plant part.
They can also be provided on a matrix material which is then provided to a plant or plant part.
The compositions containing the flagellin-associated bioactive priming polypeptides can also be provided for direct delivery into a plant, plant tissues or a plant cell by various delivery methods, for example, injection, inoculation or infiltration (for example, infiltration into the stomata on the leaf). These polypeptides can also be provided in a manner where they can move systemically through a plant and influence signaling cascades in the plant that subsequently produce beneficial and productive outcomes to the plant or plant part.
Retro-inverso Flg bioactive priming polypeptides as described in Table 4 or Table 5 can be applied individually or in combination with any other flagellin, flagellin-associated or other bioactive priming polypeptide sequences as described herein. Combinations of such RI flagellin and flagellin-associated bioactive priming polypeptides are useful as plant protectants as well as plant growth promoting enhancers.
The signature (SEQ ID NO: 542-548; Table 6), signal anchor sorting (SEQ ID NO: 549-562, Table 7) and secretion assistance polypeptides (SEQ ID NOs 563-570; Table 8) can be used in combination with any of the flagellin coding (Table 1), N and/or C-terminal conserved sequences from Bacillus-derived flagellins (Table 2), flagellin-associated polypeptides: Flg22 and FlgII-28 (Table 3), the retro inverso forms of Flg22 and FlgII-28 (Table 4) or any of the other Flgs (Table 5) as described herein.
For example, any of the Flg-associated bioactive priming polypeptides or combinations thereof can be provided in individual formulations and applied either simultaneously, sequentially in separate formulations or provided as fusion protein(s) that contain the assistance sequences as described in Tables 6-8 and applied directly or separately to a plant or plant part.
Harpin-like polypeptides or RHPP polypeptides can provide functional benefits when applied both exogenously, for example as a foliar spray to the plant surface, or provided apoplastically (to the space outside of the plant cell membrane) or endogenously (inside a plant cell/plant cell membrane). RHPP polypeptides can also provide functional benefits when applied as a seed treatment.
Foliar or in furrow applications of harpin-like, HpaG-like polypeptides are useful to enhance growth, increase biomass, and greenness or chlorophyll production of a plant.
The PSKα bioactive priming polypeptide(s) can be provided for delivery to a plant surface/plant plasma membrane as a foliar spray or, a seed treatment to an area surrounding a plant, plant part or a plant cell.
The compositions containing the PSKα bioactive priming polypeptides can also be provided for delivery into a plant, plant tissues or a plant cell by various delivery methods, for example, injection, inoculation or infiltration (for example, added directly or prerequisitely to cell culture).
V. Methods of UseMethods are provided for increasing growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part and/or decreasing abiotic stress in the plant or the plant part and/or protecting the plant or the plant part from disease, insects and/or nematodes, and/or increasing the innate immune response of the plant or the plant part and/or changing plant architecture. The method can comprise applying the polypeptide or the composition as described herein to a plant, a plant part, or a plant growth medium or a rhizosphere in an area surrounding the plant or the plant part to increase growth, yield, health, longevity, productivity, and/or vigor of the plant or the plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change the plant architecture.
Alternatively, the method can comprise applying the polypeptide or the composition as described herein to a plant growth medium to increase growth, yield, health, longevity, productivity, and/or vigor of a plant or a plant part to be grown in the plant growth medium and/or decrease abiotic stress in the plant or the plant part to be grown in the plant growth medium and/or protect the plant or the plant part to be grown in the plant growth medium from disease, insects and/or nematodes, and/or increase the innate immune response and/or change plant architecture of the plant or the plant part to be grown in the plant growth medium.
Another method comprises applying the recombinant microorganism as described herein to a plant, a plant part, or a plant growth medium or a rhizosphere in an area surrounding the plant or the plant part to increase growth, yield, health, longevity, productivity, and/or vigor of the plant or the plant part and/or decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part and/or change the plant architecture. The recombinant microorganism expresses the polypeptide and expression of the polypeptide is increased as compared to the expression level the polypeptide in a wild-type microorganism of the same kind under the same conditions.
Methods using the bioactive priming polypeptides are also provided to increase the overall plant productivity in a field, orchard, planting bed, nursery, timberland, farm, lawn, garden, garden center or acreage. Applications and methods using the bioactive priming polypeptides are also useful for increasing plant growth, health and productivity in diverse crops (monocots and dicots), for example, corn, wheat, rice, sugarcane, soybean, sorghum, potatoes and a variety of vegetables.
A “bioactive polypeptide priming” approach is also provided by direct application of the polypeptides, which can be applied either exogenously to a plant cell surface or endogenously to the interior of a plant and/or a plant cell. The polypeptides are provided for delivery to the plant surface or plasma cell membrane or to the interior of a plant, plant tissue or cell and are useful for regulating developmental processes that result in enhanced growth phenotypes such as increases in overall biomass, vegetative growth, seed fill, seed size, and number of seed that contribute to increases in the total yield of crop plants.
Application of the retro-inverso Flg polypeptides provided in agricultural formulations can result in enhanced plant protection from diseases and abiotic stresses while synergistically enhancing growth, productivity and yield while maintaining increased plant health with enhanced plant performance for longer periods of time.
Selection of the native L (Table 3) or the retro-inverso D (Table 4) forms of the Flg-associated polypeptides can depend on the environment, the plant/crop, or the combination of plant/crop and environment. In addition, the timing of the treatment application (for example, a foliar spray application) during the growing season are all relevant considerations. The retro inverso Flg bioactive priming polypeptides have enhanced binding affinity to cell surface membranes. Due to these features, the RI forms of the Flg bioactive priming polypeptides can be used to improve abiotic stress tolerance in a plant or plant part.
Additionally, the retro inverso forms of RI Ec.Flg22 and RI Bt.4Q7Flg22 can be useful to stimulate the closure of stomata under conditions of drought and heat stress and improve yields under those conditions. Control of stomatal closure using Flg-associated bioactive priming polypeptide applied to a plant during periods of environmental stress can assist in the regulation of water loss and stabilize turgor pressure in a plant when environmental conditions are unfavorable.
In the methods, the polypeptide or the composition can comprise: the Flg22 polypeptide and an amino acid sequence of the Flg22 polypeptide comprising any one of SEQ ID NOs: 226-300 and 571-573; the retro inverso Flg22 polypeptide and an amino acid sequence of the retro inverso Flg22 polypeptide comprising any one of SEQ ID NO: 376-450; or any combination thereof to protect the plant or the plant part from disease and/or increase the innate immune response of the plant or the plant part.
In the methods, the polypeptide or the composition can comprise: the FlgII-28 polypeptide and an amino acid sequence of the FlgII-28 polypeptide comprising any one of SEQ ID NOs: 301-375; the retro inverso FlgII-28 polypeptide and an amino acid sequence of the retro inverso FlgII-28 polypeptide comprising any one of SEQ ID NO: 451-525; or any combination thereof to protect the plant or the plant part from disease and/or increase the innate immune response of the plant or the plant part.
In the methods, the polypeptide or the composition can comprise the FlgII-28 polypeptide and an amino acid sequence of the Flg22 polypeptide can comprise any one of SEQ ID NO: 226, 571, or 752 and/or EF-Tu polypeptides, the amino acid sequence of the EF-Tu polypeptides comprising SEQ ID NOs: 616 and 617, to protect the plant or the plant part from disease and/or increase the innate immunity of the plant or plant part. In the methods, the amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 226, 289, 290, 291, 293, 294, 295, 300, 437, 532, 534, 536, 538, 540, 571-586, and 751-766 or any combination thereof to protect the plant or the plant part from disease, insects or nematodes. These are polypeptides with mutant sequences exhibiting increased activity to reactive oxygen species. For example, the amino acid sequence of the flagellin or flagellin-associated polypeptide can comprise any one of SEQ ID NOs: 226, 293, 295, 300, 540, 571 574, 751 and 752 or any combination thereof.
The disease can comprise Asian citrus greening, Huanglonging (HLB) disease, Asian soybean rust, Sclerotinia stem rot (or white mold), Pseudomonas leaf spot, or Cercospora leaf blight.
In the methods, the polypeptide or the composition can comprise the Flg22 polypeptide and an amino acid sequence of the Flg22 polypeptide comprising any one of SEQ ID NOs: 226-300 and 571-573 or any combination thereof.
In the methods, the polypeptide or the composition can comprise the FlgII-28 polypeptide and an amino acid sequence of the FlgII-28 polypeptide comprising any one of SEQ ID NOs: 301-375 or 751 or any combination thereof.
In the methods, the polypeptide or the composition can comprise the Flg22 polypeptide and the FlgII-28 polypeptide, an amino acid sequence of the Flg22 polypeptide comprising any one of SEQ ID NOs: 226-300 and 571-573 or any combination thereof and an amino acid sequence of the FlgII-28 polypeptide comprising any one of SEQ ID NOs: 301-375 or 751 or any combination thereof. The polypeptide or the composition can further comprise the retro inverso Flg22 polypeptide, the retro inverso FlgII-28 polypeptide or a combination thereof, an amino acid sequence of the retro inverso Flg22 polypeptide comprising any one of SEQ ID NO: 376-450 or any combination thereof and an amino acid sequence of the retro inverso FlgII-28 polypeptide comprising any one of SEQ ID NO: 451-525 or any combination thereof.
In the methods, the polypeptide or the composition can comprise the RHPP polypeptide and/or the RI RHPP polypeptide to increase the yield, the growth and/or the productivity of the plant or plant part and/or change the plant architecture.
When the method includes a polypeptide or composition comprising the RHPP polypeptide and/or the RI RHPP polypeptide, the growth can comprise root growth, root length, root biomass, nodulation, total biomass, above ground biomass, or any combination thereof. When the polypeptide or composition comprises the RHPP polypeptide, the amino acid sequence of the RHPP polypeptide can comprise SEQ ID NO: 600.
When the method includes a polypeptide or composition comprising the RHPP polypeptide and/or the RI RHPP polypeptide, the plant can comprise soybean, the growth can comprise overall root length, root biomass, nodulation, nodules per plant, total biomass, above ground biomass, or any combination thereof, and the productivity can comprise number of total pods or pods per node.
The plant architecture can comprise beneficial outcomes to the plant or plant part. For example, the beneficial outcomes can include increased planting density capability for a field of the plants.
In the methods, the polypeptide or the composition can comprise the harpin-like polypeptide or the RHPP polypeptide to protect the plant or the plant part from disease, insects and/or nematodes, and/or increase the innate immune response of the plant or the plant part.
In the methods, the polypeptide or the composition can comprise the PSK polypeptide to increase yield of the plant or the plant part in environments prone to heat and drought.
The polypeptide, the composition, or the recombinant microorganism can be applied just prior to floral formation or at the pre-flowering stage.
In the methods, the polypeptide or the composition can comprise the PSK polypeptide, the RHPP, the harpin or harpin-like polypeptide, or a combination thereof to increase growth of the plant or the plant part.
The growth can comprise root and floral apical meristems, floral organ production, fruit development, fruit production, number of floral organs, size of floral organs, or a combination thereof.
In the methods, the polypeptide or the composition can comprise the PSK polypeptide and the harpin or harpin-like polypeptide to increase growth and productivity of the plant or the plant part in an environment prone to both stress and non-stress conditions for plant growth.
In the methods, the polypeptide or the composition can comprise the thionin or thionin-like polypeptide.
The thionin or thionin-like polypeptide can be fused to a phloem targeting sequence to form a fused polypeptide, the amino acid sequence of the phloem targeting sequence comprising any one of SEQ ID NOs: 641-649, or any combination thereof, for delivering the fused polypeptide to vascular tissue or cells and/or phloem or phloem-associated tissue or cells in the plant or plant part.
In the methods, protecting the plant or the plant part from disease can comprise prophylactic treatment, treatment, prevention and decreased disease progression on or in the plant or plant part.
The disease can comprise Asian citrus greening disease (HLB), Citrus canker disease, Cercospora leaf blight or a bacteria causing disease.
The bacteria causing disease can comprise bacterial leaf blight, bacterial leaf streak, bacterial stalk rot, bacterial leaf spot, bacterial leaf scorch, bacterial top rot, bacterial stripe, chocolate spot, Goss's bacterial wilt and blight, Holcus spot, purple leaf sheath, seed rot, seedling blight, Stewart's disease (bacterial wilt), corn stunt, Fire Blight, Pierce's disease, citrus variegated chlorosis, citrus canker, Pseudomonas syringae serovars, or a combination thereof.
In the methods, the polypeptide or the composition further can comprise the flagellin or flagellin-like polypeptide, and an amino acid sequence of the flagellin or flagellin-like polypeptide comprising any one of SEQ ID NOs: 226-525 and 571-573 or any combination thereof.
In the methods, the polypeptide, the composition, or the recombinant microorganism can be applied exogenously to the plant, the plant part, or the plant growth medium.
In the methods, the polypeptide, the composition, or the recombinant microorganism can be applied endogenously to the plant or the plant part.
The plant part can include a plant cell, a leaf, a branch, a stem, a flower, a foliage, a floral organ, a fruit, pollen, a vegetable, a tuber, a rhizome, a corm, a bulb, a pseudobulb, a pod, a root, a root ball, a root stock, a scion, or a seed.
In the methods, the polypeptide, the composition, or the recombinant microorganism can be applied to a surface of the plant, a foliage of the plant or a surface of a seed of the plant.
In the methods, the polypeptide, the composition, or the recombinant microorganism can be applied to the surface of the seed and the plant or the plant part is grown from the seed.
In the methods, the polypeptide, the composition, or the recombinant microorganism can be applied as a foliar application.
The plant can be a fruit plant or a vegetable plant, and the method provides increased yield of fruits or vegetables.
In methods where the bioactive priming polypeptides are applied two or more times during a growing season, the first application can occur at or before the V2 stage of development, and subsequent applications can occur before the plant flowers. For example, the first application can occur as a seed treatments, at/or before the VE stage of development, at or before the V1 stage of development, at or before the V2 stage of development, at or before the V3 stage of development, at or before the V4 stage of development, at or before the V5 stage of development, at or before the V6 stage of development, at or before the V7 stage of development, at or before the V8 stage of development, at or before the V9 stage of development, at or before the V10 stage of development, at or before the V11 stage of development, at or before the V12 stage of development, at or before the V13 stage of development, at or before the V14 stage of development, at or before the V15 stage of development, at or before the VT stage of development, at or before the R1 stage of development, at or before the R2 stage of development, at or before the R3 stage of development, at or before the R4 stage of development, at or before the R5 stage of development, at or before the R6 stage of development, at or before the R7 stage of development, or at or before the R8 stage of development. By way of example, the first application can occur at or before the germination stage, at or before the seedling stage, at or before the tillering stage, at or before the stem elongation stage, at or before the booting stage, or at or before the heading stage. For example, where the Feekes scale is used to identify the stage of growth of a cereal crop, the first application can occur at or before stage 1, at or before stage 2, at or before stage 3, at or before stage 4, at or before stage 5, at or before stage 6, at or before stage 7, at or before stage 8, at or before stage 9, at or before stage 10, at or before stage 10.1, at or before stage 10.2, at or before stage 10.3, at or before stage 10.4, or at or before stage 10.5.
Abiotic Stress
Abiotic stress causes significant crop loss and can result in major reductions in crop production and yield potential. The bioactive priming polypeptides and compositions as described herein can be used as chemical priming agents to increase tolerance of a plant to one or more abiotic stresses. Thus, the flagellin polypeptides, flagellin-associated polypeptides of Flg22 or FlgII-28 derived from Bacillus species, Flg15 and Flg22 derived from E. coli and other organisms (Table 5) and the RHPP polypeptides derived from Glycine max (Tables 13 to 15) are useful for increasing the tolerance of a plant, group of plants, field of plants and/or the parts of plants to abiotic stress. The polypeptides and compositions as described herein impart abiotic stress tolerance to a plant or plant part. The abiotic stress tolerance imparted to a plant or plant part are to abiotic stresses that include, but are not limited to: temperature stress, radiation stress, drought stress, cold stress, salt stress, osmotic stress, nutrient-deficient or high metal stress, and water stress that results from water deficit, flooding or anoxia. Chemical priming using the bioactive priming polypeptides and compositions as described herein are applied to a plant or plant part offering a versatile approach to protect the plant or plant part against individual, multiple or combined abiotic stresses.
The polypeptides and compositions as described herein are effective to protect a plant against abiotic stressors when applied as an above ground foliar application to a plant, a plant part, a plant root, a plant seed, a plant growth medium, or the area surrounding a plant or the area surrounding a plant seed. For example, for trees, one or more applications can be applied at different growth timings of trees, including timings before, during or after flushes; before, during, or after fruit set; or before or after fruit harvest.
The methods described herein chemically prime the plant for protection against abiotic stress(es) in such a way that the plant has already prepared and initiated defense mechanisms that can be activated faster and increase tolerance to an abiotic stress or multiple stressors occurring simultaneously or at different times during the growing season.
The retro inverso forms of the Flg22 polypeptides as described herein can be applied externally as a foliar spray application (or using other application methods as well, for example as a root drench) during times of excessive heat, water, and drought stress and be used to protect a plant against drought, heat stress and/or other abiotic stresses that can affect stomatal aperture and oscillation that commonly occur with transpiration loss through a plant.
In the methods, the polypeptide or the composition can comprise: the Flg22 polypeptide and an amino acid sequence of the Flg22 polypeptide comprising any one of SEQ ID NOs: 226-300 and 571-573 or any combination thereof; the retro inverso Flg22 polypeptide and an amino acid sequence of the retro inverso Flg22 polypeptide comprising any one of SEQ ID NO: 376-450 or any combination thereof; or any combination thereof to decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease and/or increase the innate immune response of the plant or the plant part.
In the methods, the polypeptide or the composition can comprise: the FlgII-28 polypeptide and an amino acid sequence of the FlgII-28 polypeptide comprising any one of SEQ ID NOs: 301-375 or any combination thereof; the retro inverso FlgII-28 polypeptide and an amino acid sequence of the retro inverso FlgII-28 polypeptide comprising any one of SEQ ID NO: 451-525 or any combination thereof; or any combination thereof to decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease and/or increase the innate immune response of the plant or the plant part.
In the methods, the polypeptide or the composition can comprise: the retro inverso Flg22 polypeptide and an amino acid sequence of the retro inverso Flg22 polypeptide comprising any one of SEQ ID NO: 376-450 or any combination thereof; the retro inverso FlgII-28 polypeptide and an amino acid sequence of the retro inverso FlgII-28 polypeptide comprising any one of SEQ ID NO: 451-525 or any combination thereof; or any combination thereof to decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease and/or increase the innate immune response of the plant or the plant part.
In the methods, the polypeptide or the composition can comprise the RHPP polypeptide and an amino acid sequence of the RHPP polypeptide comprises SEQ ID NO: 600, 603, 604 or any combination thereof; the Kunitz Trypsin Inhibitor (KTI) polypeptide and an amino acid sequence of the KTI polypeptide comprises SEQ ID NO: 602; the retro-inverso RHPP polypeptide and an amino acid sequence of the RI RHPP comprises SEQ ID NO 601, 605, 606 or any combination thereof; or any combination thereof to decrease abiotic stress in the plant or the plant part and/or protect the plant or the plant part from disease and/or increase the innate immune response of the plant or the plant part.
The abiotic stress can comprise heat stress, temperature stress, radiation stress, drought stress, cold stress, salt stress, nutrient-deficient stress, high metal stress, water stress, osmotic stress, or any combination thereof.
Balancing Immune Response with Plant Growth and Development
Although immune responses can provide protection of plants from pathogen attack, excessive immune responses may have negative impacts on plant growth. Therefore, balancing enhanced immunity or disease prevention and protection in a plant with an increased growth promoting response is a desired combination to optimize plant health.
Bioactive priming polypeptides that are useful for enhancing immune responses as described herein can be combined with polypeptides that provide positive impacts on plant growth and productivity. The polypeptide combinations are specifically selected for their distinct modes of action/regulation when applied to a plant or plant part. However, some of the bioactive priming polypeptides (Flgs, HpGa-like, PSKα, thionins) are perceived by receptor-like proteins, followed by a process that initiates their entry and transport in the plant which results in functional outcomes while others are taken into the plant by active absorption (e.g., RHPP). For example, PSKα and the Flg-associated polypeptides such as Flg22, Flg25 and FlgII-28 are perceived by a leucine-rich receptor kinase located on the surface of the plasma membrane and involve a complex signaling pathway involved in the pathogen-triggered responses leading to immunity, disease resistance or disease prevention (Kutschmar et al. “PSKα promotes root growth in Arabidopsis,” New Phytologist 181: 820-831, 2009).
The bioactive priming polypeptides as described herein such as Flg22 HpaG-like polypeptides and thionins can act as elicitors and exhibit antimicrobial activity (e.g., anti-pesticide; bacterial, fungal, or viral activity). Specific combinations of polypeptides are provided, for example, the combination of flagellin- and harpin-associated bioactive priming polypeptides are useful for preventing and protecting plants from pathogenic diseases and serve a dual utility when they are applied together with those other polypeptides, for example, PSKα and RHPP, that enhance plant growth and productivity in a plant, plant part, and/or field of plants.
The combinations of bioactive priming polypeptides as described herein can be applied exogenously as a foliar spray, in furrow treatment, seed treatment, drench or wash or endogenously to a plant to stimulate both the immune responsiveness and growth characteristics of the plant that collectively result in improved yield performance. They can also provide protection and growth benefits to the different parts of the plant (for example, leaves, roots, tubers, corms, rhizomes, bulbs, pseudobulbs, flowers, pods, fruits, and growing meristems).
The combined foliar application or sequential applications of PSKα with HpaG-like bioactive priming polypeptides can be useful for enhancing growth of plants under standard (non-stress or optimal growth) environments or of plants exposed to abiotic stress (for example, heat, and water deficit stress).
Foliar application treatments using the X.spp HpaG-like and the At.PSKα bioactive priming polypeptides have different modes of action when applied on plants in optimal (non-stress) and in stress environments. The two classes of bioactive priming polypeptides are useful either provided sequentially or in combination in a foliar application and can improve plant growth in an environment that is with or without abiotic stress(es).
X.spp.HpGa-like provides a plant growth benefit to corn in a non-stress environment where temperature, water, nutrients and other environmental parameters were conducive to optimal plant growth. On the other hand, At.PSKα applied as a foliar spray provides a benefit to plant growth under environmental conditions of heat and drought or water deficit stress. Thus, when used in combination in formulation together as foliar applications they can span both non-stress and stress environments and provide additive benefits to the growth of corn plants grown in a variety of environmental conditions.
Increases in plant productivity and growth for At.PSKα is also seen in soybean plants grown in environments with and without abiotic stress. Soybean plants that receive a foliar application with a formulation containing the bioactive priming polypeptide At.PSKα and are grown under conditions of heat and drought stress have increased yield over control soybean plants that received water and surfactant with no bioactive priming polypeptide.
When X. spp. HpaG-like and At.PSKα are applied as a foliar spray together, they are useful to provide synergistic effects for plant production under normal and stressed environments. At.PSKα exhibits increased overall growth in corn when applied as a spray application, whereas X. spp. HpaG-like polypeptide results in the opposite trend. Thus, applying the two bioactive priming polypeptides together can act to balance plant growth in “heat stressed” environments such that the changes in plant growth compared to control plants are greater than the sum of the effects of the bioactive priming polypeptides applied individually.
The synergistic interaction of these two classes of bioactive priming polypeptides enhance plant growth under heat stressed environments (e.g., greater growth rates with increased plant biomass).
Any of the bioactive priming polypeptides as described herein can be applied one or more times to a plant either in combination or individually to enhance growth and productivity of a plant. Multiple applications can be applied to promote yield benefits over the growing season with applications tailored to the conditions in the environment, for example if a period of hot and dry weather is expected during the growth season, an additional spray of bioactive priming polypeptides that promote growth under abiotic stress can alleviate negative impacts to the plant.
Foliar Application of Phytosulfokine Alpha (PSKα) to Increase Yield
A method is provided for applying At.PSKα as a foliar application to actively growing soybean plants to provide a yield advantage in environments with heat and drought stress. For example, a means of applying a composition containing bioactive priming At.PSKα polypeptide is provided as a foliar spray to soybean at V1-V4 stage using application methods as described herein. Soybean plants treated with foliar applications of At.PSKα can be grown in field environments under conditions that produced a non-stress and stress (heat and water deficit) environments. Treatment with At.PSKα can result in growth and yield benefits in plants grown in a variety of environmental conditions including abiotic stressors.
Any of the RHPP bioactive priming polypeptides provided in Tables 12-14 can be applied as a foliar, in furrow, seed treatment or root drench application to a plant surface.
Foliar application of RHPP results in the alteration of plant architecture.
A method is provided where the RHPP polypeptide is applied as a foliar application to plants and results in a distinct leaf architecture (corn) and an enhanced root system (soybean). The increase in leaf angle and root biomass using a foliar treatment with RHPP has impactful advantages for use in agriculture in two major agriculture crops (corn and soybean).
Application of RHPP to Alter Plant Architecture
Applying the bioactive priming polypeptide, RHPP, as a foliar application to V5-V8 corn results in a distinct leaf architecture phenotype with an upright leaf orientation and more erect leaves. This is particularly relevant with higher planting densities used to maximize yield in a field environment. Foliar applications of the RHPP polypeptide in maize (corn) is useful for changing the leaf angle thus contributing to a smaller leaf angle which results in an upright leaf orientation. This phenotype can be beneficial for increasing the leaf area index, reducing maize shade syndrome, and improving photosynthetic efficiency. In addition, providing RHPP as a foliar formulation to maximize canopy development and total light penetrance is key to increasing vegetative growth of the plants prior to the initiation of the grain filling stage.
Maize plants exhibit leaf curl or changes in their leaf architecture to a more upright leaf orientation to conserve water and enhance plant tolerance to drought and heat. The upright changes to the leaf phenotype for corn after application with the RHPP bioactive priming polypeptide(s) compositions are useful and provide an alternative non-breeding approach for shaping leaf architecture and enhancing tolerance to drought and heat.
An upright leaflet orientation phenotype in corn plants functions in the reduction of leaf temperatures, whole plant transpiration and in the improvement of water use efficiency, as well as provide architectural changes to the plant canopy which can allow for higher density plantings that result in substantial increases in yield.
Application of the bioactive priming polypeptide, RHPP, to soybeans can also provide benefits. For example, foliar application of RHPP to flowering soy can increase pod set. Pod set is a stage in soybean development occurring from the middle of R4 to the middle of R5 that contributes directly to yield. Initial pod set is marked by the emergence of a ¾ inch pod at one of the four uppermost nodes on the main stem. It then progesses to the full pod stage where pod growth is rapid and seed development begins. An increase in pod set is quantified by an increase in yield (i.e the pod number per node on a plant or the overall number of pods per plant).
RHPP to Increase Root Biomass and Yield
Soybean plants treated with foliar applied RHPP (SEQ ID NO: 600) bioactive priming polypeptide(s) can exhibit increased pod filling and a more-complete pod filing compared to non-treated plants which can be the result of increases in nitrogen fixation.
Root architecture, particularly a root system with a rapid exploitation of deep soil can optimize nitrogen capture and water uptake which is especially important in drying and nitrogen depleted soils. An RHPP polypeptide(s) as described herein when applied as a foliar treatment to soybean plants results in a root phenotype that is useful for water and mineral (nitrogen) acquisition, especially in nitrogen-deficient soils. Increasing nutrient uptake efficiency by enhancing root architecture is a key factor for improving plant productivity when used with soybean cultivation practices in a wide range of soil types.
Enhanced root biomass that results from a foliar application of RHPP provided at the early vegetative stages for soybean VE-V5 or V2-V3 stage of development results in a root system with rapid exploitation of deep soil (deep roots), and greater overall increases in root biomass. For example, a root hair promoting bioactive priming polypeptide such as RHPP (SEQ ID NO: 600) can be applied as a foliar treatment to soybean plants at the V2 to V3 stage of development to result in an overall increase in root biomass. Other notable enhancements in addition to root biomass are the production of longer lateral roots, increases in root branching, root hairs and increases in the root absorptive surface area.
RHPP can be applied as a foliar treatment at key developmental stages (VE-V8 or V2-V8) or in environments where a rapid increase in root production is desired, such as dry or nutrient poor soil types. Soil types in particular may affect root development and expansion. For example, if plants have a hard time emerging in a clay soil, it may affect root formation and root proliferation. Increasing root mass may not only beneficially effect plant emergence but also contribute to plant establishment. In addition, nodule formation and number are important because the bacteria that inhabit the nodules pull nitrogen from the air allowing soybeans to convert it into the nitrogen that they need to grow and produce seeds.
The RHPP polypeptides (Tables 13-15) can be used to increase nodule formation and nodule production of soybean roots when applied using any of these treatment application methods which can be applied directly to the soil, as a soil drench, as an in furrow treatment, or as a foliar application to the above ground plant parts.
Increase in nodules can result in increased nitrogen fixation by nitrogen fixing bacteria that inhabit the root nodules, such as Rhizobium leguminosarum or japonicum. Nodule formation can be seen shortly after VE and can increase nitrogen fixation. Effective nodulation of soybean roots results in higher yields and higher quality seed production, protein and oil per seed or acre basis. Soybean plants have fully formed first trifoliate leaves at the V1-V2 stage of development which is estimated to be the peak time for nitrogen fixation.
The combination application of Gm.RHPP bioactive priming polypeptide with various fertilizer treatment(s) can provide a yield boost and is recommended especially for crop management applications in nitrogen depleted soils.
Bacterial Disease
Methods of using the bioactive priming polypeptides such as the flagellin-associated polypeptides or the thionin-like polypeptides as described herein are useful for the prevention, treatment and control of bacterial diseases in corn and particularly useful for the treatment of bacterial leaf streak disease in corn caused by Xanthomonas vasicola pv. vasculorum, also recognized as Xanthomnas campestris pv. vasculorum.
Surveys indicate that bacterial leaf streak disease has spread and may be widely distributed throughout the U.S. Corn Belt (Western Indiana, Illinois, Iowa, Missouri, Eastern Nebraska and Eastern Kansas). Disease spread is most prevalent where corn is planted on corn in crop rotation practices. The bacterial leaf streak disease can cause infection on dent corn (field) seed corn, popcorn and sweet corn. The symptoms on corn include narrow to brown yellow streaks and brown yellow strips between the leaf veins. Lesions usually develop on lower or older plant leaves and initially spread to the higher or younger leaves on the plant. Yellow discoloration also may be present around lesions.
The bacterial leaf streak disease of corn presumably survives in previously infected host debris. Bacterial exudates found on surfaces of infected leaf tissues can serve as secondary inocula. The bacterium is spread by wind, splashing rain, and possibly by irrigation water. The pathogen penetrates corn leaves through natural openings such as stomata, which can result in a banded pattern of lesions occurring across leaves. Colonization of leaf tissues apparently is restricted by main veins.
Because the disease is caused by a bacterial pathogen, the current use of bactericides is problematic to control it. For example, most bactericides act as contact products and are not systemic and thus they will not be absorbed or taken into the plant via other mechanisms. Bactericide treatments may require repeated applications as the bactericide may be washed off with rain or wind, thus rendering them uneconomical or impractical for use in some corn crops.
Current disease management practices to date recommend crop rotation practices (such as corn, soybean and then back to corn) and the implementation of sanitation practices, such as cleaning equipment between field usage to slow disease progression.
Foliar applications of the Flg (Tables 4-5) and thionin polypeptides (Table 19) or combinations of the two classes provide an alternative approach for treating the disease. Foliar applications with these bioactive priming polypeptides provided as a spray to the leaf surface of either asymptomatic or symptomatic plants provides a means to prevent, treat, and control the bacterial leaf streak disease in corn.
Alternatively, the flagellin- and thionin bioactive priming polypeptides or combinations thereof can be useful for the prevention, treatment and control of other bacterial diseases that infect corn (Table 21).
Cercospora is a fungal pathogen that causes the disease Cercospora leaf blight of soybean. Cercospora leaf blight also referred to as the purple seed stain disease infects both the leaves and seeds of soybeans. Cercospora infection of soybean seeds diminishes seed appearance and quality. The causal organism of Cercospora leaf blight is Cercospora kikuchii, which overwinters in soybean residue and in the seed coats. Spread of the disease occurs when the spores from the fungus are spread to soybean plants from infected residue, weeds or other infected soybean plants. Disease spread and symptom development are accelerated during periods of warm and wet weather. Symptom development usually begins after flowering and appears as circular lesions on soybean leaves as reddish brown to purple spots that can merge to form lesions. Symptoms are apparent in the upper canopy, usually in the uppermost three or four trifoliate leaves. Infected soybean plants exhibit worsening symptoms as the crop matures, and premature defoliation of affected leaves may occur during pod-fill. Cercospora symptom development may also appear as lesions on stems, leaf petioles and pods. Seeds are infected through the attachment to the pod. Cercospora infected seeds show a purple discoloration, which can appear as specks or blotches covering the entire seed coat.
Foliar applications of flagellin or flagellin-associated polypeptides (Tables 4-5) provide an alternative approach for treating the disease. Foliar applications with these bioactive priming polypeptides provided as a spray to the leaf surface of either asymptomatic or symptomatic plants provides a means to prevent, treat, and control Cercospora Leaf Blight in soybeans. Foliar applications of Flg22 derived from Bacillus thuringiensis, particularly at high use rates (e.g. 4.0 Fl. oz/Ac), can provide a means of managing early symptom development and provide healthier more vigorous soybean plants grown in field locations that have been impacted by Cercospora.
Specific combinations of bioactive priming polypeptides that can be useful for treating or reducing the symptoms of Cercospora include: a flagellin or flagellin-associated polypeptide having an amino acid sequence comprising SEQ ID NO 226, 751 or 752; an RHPP polypeptide having a sequence comprising SEQ ID NO: 600; or a combination of a flagellin associated polypeptide having an amino acid sequence comprising any one of SEQ ID NOs 226, 751 and 572 and an RHPP polypeptide having the amino acid sequence comprising SEQ ID NO: 600.
For example, a useful combination of bioactive priming polypeptides for treating, or reducing the symptoms of Cercospora on a plant or plant part is a flagellin polypeptide having an amino acid sequence comprising SEQ ID NO: 226 alone or in combination with an RHPP polypeptide having an amino acid sequence comprising SEQ ID NO: 600. Additional treatments can further comprise a fungicide in combination with these bioactive priming polypeptides.
Asian Soybean Rust DiseaseAsian soybean rust is a fungal disease caused by Phakopsora pachyrhizi. Its etiology and symptoms are similar to Cercospora and the bioactive priming polypeptide combinations useful for treating it are similar as well. Specifically, combinations of bioactive priming polypeptides that can be useful for treating or reducing the symptoms of Asian soybean rust include: a flagellin or flagellin-associated polypeptide having an amino acid sequence comprising SEQ ID NO 226, 751 or 752; an RHPP polypeptide having a sequence comprising SEQ ID NO: 600; or a combination of a flagellin associated polypeptide having an amino acid sequence comprising any one of SEQ ID NOs 226, 751 and 572 and an RHPP polypeptide having the amino acid sequence comprising SEQ ID NO: 600.
For example, a useful combination of bioactive priming polypeptides for treating, or reducing the symptoms of Asian soybean rust on a plant or plant part is a flagellin polypeptide having an amino acid sequence comprising SEQ ID NO: 226 alone or in combination with an RHPP polypeptide having an amino acid sequence comprising SEQ ID NO: 600. Additional treatments can further comprise a fungicide in combination with these bioactive priming polypeptides.
Holcus SpotHolcus spot is a bacterial disease caused by Pseudomanas syringae pv. actinidae. Methods are described herein for using flagellin or flagellin associated polypeptides to restrict growth of P. syringae and thus prevent or treat the disease of Holcus spot in a plant or a plant part. Flagellin or flagellin associated polypeptides useful for the treatment of P. syringae include any polypeptides having amino acid sequences comprising any one of SEQ ID NOs: 226, 540, 751, and 572 or any combination thereof.
Sclerotinia Stem Rot (White Mold) DiseaseSclerotinia sclerotiorum is a plant pathogenic fungus that causes a disease caused white mold. It is also known as cottony rot, water soft rot, stem rot, drop, crown rot, and blossom blight. Diagnostic symptoms of the white rot include black resting structures known as sclerotia and white fuzzy growths of mycelium on the infected plant. The sclerotia, in turn, produce a fruiting body that produces spores in a sac. Sclerotinia can affect herbaceous, succulent plants, particularly fruits and vegetables, or juvenile tissue on woody ornamentals. It can also affect legumes or tuberous plants like potatoes. White mold can affect a host at any stage of growth, including seedlings, mature plants, and harvested products. It is usually found on tissues with high water content and close proximity to soil. Left untreated, pale to dark brown lesions on the stem at the soil line are covered by a white, fluffy mycelial growth. This affects the xylem which leads to chlorosis, wilting, leaf drop, and death. White mold can also occur on fruit in the field or in storage and is characterized by white fungal mycelium covering the fruit and its subsequent decay. Flagellin or flagellin associated polypeptides useful for the treatment of S. sclerotiorum include any polypeptides having amino acid sequences comprising any one of SEQ ID NOs: 226, 540, 571, 751, and 752.
Pseudomonas Leaf SpotPseudomonas syringae pv. actinidiae (PSA) is a devastating plant pathogen causing bacterial canker of both green- (Actinidiae deliciosa) and yellow-flesh (Actinidiae chinesis) kiwi plants throughout zones of kiwi production, causing severe harvest loss in New Zealand, China, and Italy. In New Zealand alone, cumulative revenue losses to the most devastating biovar PSA-V are predicted to approach $740 million New Zealand leaves Dollars (NZD) by 2025 (Agribusiness and Economics Research Institute of Lincoln University “The Costs of Psa-V to the New Zealand Kiwifruit Industry and the Wider Community”; May 2012). PSA-V colonizes the outer and inner surfaces of the kiwi plant and can spread through the xylem and phloem tissues. Disease symptoms of PSA-V on kiwi include bacterial leaf spot, bacterial canker of the trunk, red exudates, blossom rot, discoloration of twigs, and ultimately dieback of kiwi vines. The standard method of control for PSA-V currently employs frequent foliar applications of metallic copper to kiwi vines which is predicted to lead to the selection of copper-resistant form of the pathogen and loss of disease control. Novel methods of control are urgently needed.
Flagellin or flagellin associated peptides useful for the treatment of Pseudomanas syringase, particularly in kiwis, include any polypeptides having amino acid sequences comprising SEQ ID NO: 226, 540, 752, and/or 571.
Asian Citrus Greening (Huanglonging) DiseaseThe methods described herein incorporate a different approach to combating disease and additionally providing benefits of increasing the overall productivity of a plant. This approach is specifically directed to providing either exogenous or endogenous applications of the bioactive priming polypeptides that include thionins to combat disease in plants.
The thionin and thionin-like polypeptides (Table 19) and compositions thereof are useful for the prevention, treatment and control of Asian citrus greening also referred to as Huanglonging (HLB) disease, a devastating disease for citrus. HLB disease is widely distributed and has been found in most commercial and residential sites in all counties that have commercial citrus orchards.
Methods are described herein for using the thionin polypeptides (SEQ ID NOs: 650-749) to prevent the spread of and in the treatment of HLB disease.
Asian citrus greening disease is transmitted by the Asian citrus psyllid, Diaphorina citri or the two-spotted citrus psyllid, Trioza erytreae Del Guercio, which are both characterized as sap-sucking, hemipteran bug(s) in the family Psyllidae and have been implicated in the spread of citrus greening, a disease caused by a highly fastidious phloem-inhabiting bacteria, Candidatus Liberibacter asiaticus (Halbert, S. E. and Manjunath, K. L, “Asian citrus psyllids Stemorrhyncha: Psyllidae and greening disease of citrus: A literature review and assessment of risk in Florida,” Florida Entomologist 87: 330-353, 2004). Asian citrus greening or Huanglongbing disease is considered fatal for a citrus tree once the tree becomes infected.
The early symptoms of the disease on leaves are vein yellowing and an asymmetrical chlorosis referred to as blotchy mottle, which is the most diagnostic symptom of the disease. Infected trees are stunted and sparsely foliated with a blotchy mottling appearing on the foliage. Early symptoms of yellowing may appear on a single shoot or branch and with disease progression, the yellowing can spread over the entire tree. Afflicted trees may show twig dieback, and fruit drop. Fruit are often few in number, small, deformed or lopsided and fail to color properly, remaining green at the end and display a yellow stain just beneath the peduncle (stem) on a cut fruit.
The Asian citrus greening disease may also be graft transmitted when citrus rootstocks are selected for and grafted to scion varieties.
Management of citrus greening disease has proven difficult and therefore current methods for control of HLB have taken a multi-tiered integrated disease and pest management approach using 1) the implementation of disease-free nursery stock and rootstock used in grafting, 2) the use of pesticides and systemic insecticides to control the psyllid vector, 3) the use of biological control agents such as antibiotics., 4) the use of beneficial insects, such as parasitic wasps that attack the psyllid, and 5) breeding for new citrus germplasm with increased resistance to the citrus greening causing bacteria (Candidatus Liberibacter spp.). The use of cultural and regulatory measures to prevent the spread of the disease is also part of the integrated management approach. Many aspects involved in the management of citrus greening are costly both monetarily and in respect to losses in citrus production.
Interveinal application of a thionin polypeptide or mixture of thionin polypeptides can be delivered directly into the phloem (e.g., phloem cells including phloem sap, phloem companion cells and phloem sieve tube elements) where Candidatus Liberibacter can reside.
The thionins can be produced using an expression system where they can be fused to a phloem targeting sequence(s) (Table 18) and then uniquely delivered to the same vicinity where the bacteria can reside in the citrus plant.
The phloem targeted thionin bioactive priming polypeptides are useful for treating citrus plants to prevent, reduce or eliminate the spread of the Asian citrus greening disease or Huanglonging (HLB) by directly targeting the bacterium, Candidatus Liberibacter asiaticus
These phloem targeted thionins can be delivered by injection into the phloem of a shrub or tree. Additionally, they can be delivered by spraying, washing, or adding as a soak or a drench to the soil or area surrounding a plant.
Any of the phloem targeting sequences (Table 18; SEQ ID NOs: 641-649) can be used in combinations with the thionin and thionin-like polypeptides (Table 19; SEQ ID NOs: 650-749).
The bacteria that cause HLB, Candidatus Liberibacter asiaticus is difficult to isolate and culture. In order to test individual thionins and thionins with the phloem targeting sequences to determine if they are useful for the treatment of HLB disease, Agrobacterium tumefaciens can be used as a model organism to test the effectiveness on reducing the cell titer or growth of Agrobacterium prior to using the thionin or thionin combinations in an orchard setting.
The “peptide priming” methods provided herein with the thionins and/or thionin-like polypeptides (Table 19) can also be used in combination flagellin and flagellin-associated polypeptides (Tables 1-5). Combinations of the thionin- and flagellin-associated bioactive priming polypeptides can be used to prophylactically pre-treat a citrus plant by applying the bioactive priming polypeptide or a composition containing the polypeptide prior to the onset or appearance of any infection-related symptoms on the citrus shrubs or trees. This pretreatment increases resistance to the disease pathogen that causes citrus greening (Candidatus Liberibacter spp.).
The thionins provided in combination with the flagellin associated bioactive priming polypeptides provide a more comprehensive approach to disease prevention and management. The thionin and flagellin associated bioactive priming polypeptides use two distinct modes of action to prevent disease and the spread of disease.
The thionin-flagellin bioactive priming polypeptide combinations can also be used with any other integrated management approach for disease control prescribed for HLB including, but are not limited to, (1) the use of disease-free nursery stock and/or rootstocks for grafting, (2) the use of pesticides and/or systemic insecticides to control the disease-causing psyllid, (3) the use of biological control agents such as injections of antibiotics or parasitic insects that controls the psyllid, (4) breeding new varieties of citrus germplasm with increased resistance to the bacteria responsible for Asian citrus greening disease, (5) controlling parasitic plants (for example, dodder) that may spread the disease, or (6) any combination thereof.
A synthetic version of a phloem targeting polypeptide (SEQ ID NO: 641) is particularly useful in targeting anti-microbial polypeptides to the phloem sieve tube and companion cells and can be useful for treating various bacterial diseases of plants, such as bacterial leaf streak, Asian citrus greening or Huanglonging and citrus canker.
In addition, flagellin or flagellin associated polypeptides are useful for treating Asian citrus greening, especially when used in combination with a bacteriocide. For instance, flagellin or flagellin associated polypeptides having amino acid sequences comprising any one of SEQ ID NOs: 226, 571, and 752 can be used. Preferably, the bacteriocide comprises oxytetracycline.
Citrus Canker“Peptide priming” methods were developed for use with the bioactive priming thionin and flagellin-associated polypeptides as described in Table 19 (thionins) and Tables 1-5 (flagellin and flagellin-associated polypeptides) to prophylactically treat citrus plants prior to any visible symptoms of the citrus canker disease or as a treatment once the onset of disease symptoms become apparent.
Citrus canker occurs primarily in tropical and sub-tropical climates and has been reported to occur in over thirty countries including spread of infection reported in Asia, Africa, the Pacific and Indian Oceans Islands, South America, Australia, Argentina, Uruguay, Paraguay, Brazil and the United States. Citrus canker is a disease caused by the bacterium, Xanthomonas axonopodis pv. citri or pv. aurantifolii (also referred as Xanthomonas citri subsp. citn) that infect foliage, fruit and young stems. Symptoms of citrus canker infection on leaves, and fruit of the citrus shrubs/trees can result in leaf-spotting, leaf lesions, defoliation, die back, deformation of fruit, fruit rind-blemishing, pre-mature fruit drop, and canker formation on leaves and fruits. Diagnostic symptoms of citrus canker include a characteristic yellow halo that surrounds the leaf lesions and a water-soaked margin that develops around the necrotic tissue on the leaves of the citrus plant. The citrus canker pathogen can spread through the transport of infected fruit, plants, and equipment. Dispersal can also be facilitated by the wind and rain. Overhead irrigation systems may also facilitate movement of the citrus canker causing pathogen. Infected stems can harbor the citrus canker causing bacteria (Xanthomonas axonopodis pv. citn) in the stem lesions for transmission to other citrus plants. Insects, such as the Asian leafminer (Phyllocnistis citrella) also disemminate the disease.
In general, citrus plants susceptible to the citrus canker disease include orange, sweet orange, grapefruit, pummelo, mandarin tangerine, lemon, lime, swingle acid lime, palestine sweet lime, tangerine, tangelo, sour orange, rough lemon, citron, calamondin, trifoliate orange and kumquat. World-wide, millions of dollars are spent annually on prevention, sanitation, exclusion, quarantine and eradication programs to control citrus canker (Gottwald T. R. “Citrus Canker,” The American Phytopathological Society, The Plant Health Instructor 2000/updated in 2005). Treatment for the disease has included application of antibiotics or disinfectants, the use of copper-based bactericidal sprays, and pesticide applications for Asian leafminer control.
The bioactive priming polypeptide combination comprising the thionin and the flagellin-associated polypeptides can be applied to a citrus plant or citrus plant part (e.g., rootstock, scion, leaves, roots, stems, fruit, and foliage) using application methods that can comprise: spraying, inoculating, injecting, soaking, infiltrating, washing, dipping and/or provided to the surrounding soil as an in furrow treatment.
The methods are provided using the bioactive priming polypeptides comprising the thionin and/or flagellin-associated polypeptides to pre-treat citrus plants or citrus plant parts (e.g., root stock, scion, leaves, roots, stems, fruit, and foliage) prior to any visible occurrence of symptoms. They are also useful for providing an increase in resistance to the citrus canker pathogen resulting in a reduction in disease symptoms.
Additionally, the methods of using the bioactive priming polypeptides such as the flagellin and flagellin-associated polypeptides are useful to treat citrus plants or citrus plant parts (e.g., root stock, scion, leaves, roots, stems, fruit, and foliage) once the early onset of citrus canker disease symptoms or when the symptoms of the disease become apparent.
Application of the Flg polypeptides for treating citrus plants to prevent, reduce or eliminate the spread of the citrus canker disease can be delivered by injecting into the phloem of a shrub or tree, spraying, washing, adding as a soak or a drench to the soil or soil area surrounding a plant or provided in furrow.
Thionin bioactive priming polypeptides as described herein (Table 17) can be applied individually or in combination with any of the flagellin-associated Flg polypeptides (Tables 1-5) as a foliar treatment or spray or as an injection and are useful for the prevention of infestation of citrus plants from insects such as the Asian leafminer (Phyllocnistis citrella) that have been identified in the dissemination of the bacteria (Xanthomonas axonopodis pv. citri) that cause the citrus canker disease.
Citrus PlantsAny of the methods described herein to provide improved plant health, disease tolerance or disease treatment applications to treat or prevent Asian citrus greening (HLB) or citrus canker are suitable for use with any citrus plants and shrubs/trees.
The thionin or flagellin-associated polypeptides or compositions comprising the thionin or flagellin-associated polypeptides as described herein can be applied to any citrus shrub and/or tree and to any agronomically-important citrus hybrid or citrus non-hybrid plant, and are useful for prophylactically treating the citrus to prevent the onset of an infection or providing treatment after an infection has occurred.
Citrus plant species for use of the methods described herein include, but are not limited to: Sweet orange (Citrus sinensis, Citrus maxima x Citrus reticulata), Bergamot Orange (Citrus bergamia, Citrus limetta x Citrus aurantium), Bitter Orange, Sour Orange or Seville Orange (Citrus aurantium, Citrus maxima x Citrus reticulata), Blood Orange (Citrus sinensis), Orangelo or Chironja (Citrus paradisi x Citrus sinensis), Mandarin Orange (Citrus reticulate), Trifoliate Orange (Citrus trifoliata), Tachibana Orange (Citrus tachibana), Clementine (Citrus clementina), Cherry Orange (Citrus kinokuni), Lemon (Citrus limon, Citrus maxima x Citrus medica), Indian Wild Orange (Citrus indica), Imperial Lemon (Citrus limon, Citrus medica x Citrus paradisi), Lime (Citrus latifoli, Citrus aurantifolia), Meyer Lemon (Citrus meyeri); hybrids of Citrus x meyeri with Citrus maxima, Citrus medica, Citrus paradisi and/or Citrus sinensis), Rough Lemon (Citrus jambhin), Volkamer Lemon (Citrus volkameriana), Ponderosa Lemon (Citrus limon x Citrus medica) Kaffir Lime (Citrus hystrix or Mauritius papeda), Sweet Lemon, Sweet Lime, or Mosambi (Citrus limetta), Persian Lime or Tahiti Lime (Citrus latifolia), Palestine Sweet Lime (Citrus limettioides), Winged Lime (Citrus longispina), Australian Finger Lime (Citrus australasica), Australian Round Lime (Citrus australis), Australian Desert or Outback Lime (Citrus glauca), Mount White Lime (Citrus garrawayae), Kakadu Lime or Humpty Doo Lime (Citrus gracilis), Russel River Lime (Citrus inodora), New Guinea Wild Lime (Citrus warburgiana), Brown River Finger Lime (Citrus wintersii), Mandarin Lime (Citrus limonia; (hybrids with Citrus reticulata x Citrus maxima x Citrus medica), Carabao Lime (Citrus pennivesiculata), Blood Lime (Citrus australasica x Citrus limonia) Limeberry (Triphasia brassii, Triphasia grandifolia, Triphasia trifolia), Grapefruit (Citrus paradisi; Citrus maxima x Citrus x sinensis), Tangarine (Citrus tangerina), Tangelo (Citrus tangelo; Citrus reticulata x Citrus maxima or Citrus paradisi), Minneola Tangelo (Citrus reticulata x Citrus paradisi), Orangelo (Citrus paradisi x Citrus sinensis), Tangor (Citrus nobilis; Citrus reticulata x Citrus sinensis), Pummelo or Pomelo (Citrus maxima), Citron (Citrus medica), Mountain Citron (Citrus halimii), Kumquat (Citrus japonica or Fortunella species), Kumquat hybrids (Calamondin, Fortunella japonica; Citranqequat, Citrus ichangensis; Limequat, Citrofortunella floidana; Orangequat, hybrid between Satsuma mandarin x Citrus japonica or Fortunella species; Procimequat, Fortunella hirdsiie; Sunquat, hybrid between Citrus meyeri and Citrus japonica or Fortunella species; Yuzuquat, hybrid between Citrus ichangensis and Fortunella margarita), Papedas (Citrus halimii, Citrus indica, Citrus macroptera, Citrus micrantha), Ichang Papeda (Citrus ichangensis), Celebes Papeda (Citrus celebica), Khasi Papeda (Citrus latipes), Melanesian Papeda (Citrus macroptera), Ichang Lemon (Citrus ichangensis x Citrus maxima), Yuzu (Citrus ichangensis x Citrus reticulata), Cam sành (Citrus reticulata x Citrus maxima), Kabosu (Citrus sphaerocarpa), Sudachi (Citrus sudachi), Alemow (Citrus macrophylla), Biasong (Citrus micrantha), Samuyao (Citrus micrantha), Kalpi (Citrus webberi), Mikan (Citrus unshiu), Hyuganatsu (Citrus tamurana), Manyshanyegan (Citrus mangshanensis), Lush (Citrus crenatifolia), Amanatsu or Natsumikan (Citrus natsudaidai), Kinnow (Citrus nobilis x Citrus deliciosa), Kiyomi (Citrus sinensis x Citrus unshiu), Oroblanco (Citrus maxima x Citrus paradisi), Ugli (Citrus reticulata x Citrus maxima and/or Citrus x paradisi), Calamondin (Citrus reticulata x Citrus japonica), Chinotto (Citrus myrtifolia, Citrus aurantium or Citrus pumila), Cleopatra Mandarin (Citrus reshni), Daidai (Citrus aurantium or Citrus daidai), Laraha (Citrus aurantium), Satsuma (Citrus unshiu), Naartjie (Citrus reticulata x Citrus nobilis), Rangpur (Citrus limonia; or hybrid with Citrus sinensis x Citrus maxima x Citrus reticulata), Djeruk Limau (Citrus amblycarpa), lyokan, anadomikan (Citrus iyo), Odichukuthi (Citrus odichukuthi), Ougonkan (Citrus flaviculpus), Pompia (Citrus monstruosa), Taiwan Tangerine (Citrus depressa), Shonan gold (Citrus flaviculpus or Citrus unshiu), Sunki (Citrus sunki), Mangshanyen (Citrus mangshanensis, Citrus nobilis), Clymenia (Clymenia platypoda, Clymenia polyandra), Jabara (Citrus jabara), Mandora (Mandora cyprus), Melogold (Citrus grandis x Citrus paradisiil Citrus maxima/Citrus grandis), Shangjuan (Citrus ichangensis x Citrus maxima), Nanfengmiju (Citrus reticulata), and ShikwAsai (Citrus depressa).
The thionin and/or flagellin-associated priming polypeptides can be applied to any citrus plant, shrub/tree used for medicinal or cosmetic/health and beauty purposes, such as Bergamot Orange (Citrus bergamia), Sour or Bitter Orange (Citrus aurantium), Sweet Orange (Citrus macrophylla), Key Lime (Citrus aurantiifolia), Grapefruit (Citrus paradisi), Citron (Citrus medica), Mandarin Orange (Citrus reticulate), Lemon (Citrus limon, or hybrids with Citrus medica x Citrus maxima, Citrus limonia, Citrus medica x Citrus maxima x Citrus medica), Sweet Lime (Citrus limetta), Kaffir Lime, (Citrus hystrix or Mauritius papeda), Lemon hybrid or Lumia (Citrus medica x Citrus limon), (Citrus medica x Citrus maxima x Citrus medica), Omani Lime (Citrus aurantiifolia, Citrus medica x Citrus micrantha), Jambola (Citrus grandis), Kakadu Lime or Humpty Doo Lime (Citrus gracilis), Pomelo (Citrus retkulata), Tangor (Citrus nobilis), and Sour Lime or Nimbuka (Citrus acida).
Exemplary important citrus hybrids for fruit production are: Sweet Orange (Citrus sinensis), Bitter Orange (Citrus aurantium), Grapefruit (Citrus paradisi), Lemon (Citrus limon), Persian Lime (Citrus latifolia), Key Lime (Citrus aurantiifolia), Tangerine (Citrus tangerine) and Rangpur (Citrus limonia).
Additionally, any of the bioactive priming polypeptides, compositions, and methods as described herein can be applied to any citrus plant, shrub/tree used as a rootstock and/or a scion germplasm. The methods are particularly useful for rootstocks commonly used in grafting of citrus to enhance the merits of the scion varieties, which can include tolerance to drought, frost, disease or soil organisms (for example, nematodes). Such citrus plants that provide useful rootstocks include: Sour or Bitter Orange (Citrus aurantium), Sweet Orange (Citrus macrophylla), Trifoliate Orange (Poncirus trifoliata), Rough Lemon (Citrus jambhin), Volkamer Lemon (Citrus volkameriana), Alemow (Citrus macrophylla), Cleopatra Mandarin (Citrus reshini), Citrumelo (hybrids with x Citroncirus species), Grapefruit (Citrus paradisi), Rangpure Lime (Citrus limonia), Palestine Sweet Lime (Citrus limettioides) and Troyer Citrange (Citrus sinensis x Poncirus trifoliata or Citrus sinensis x Citrus trifoliata) and Citrange (Citrus sinensis x Poncirus trifoliata or C. sinensis x C. trifoliata).
Use of Retro-Inverso Flg Bioactive Priming Polypeptides to Treat and Reduce Citrus GreeningCombinations of flagellin-associated polypeptides paired with their retro-inverso counterparts can be used to treat and reduce the greening effect on citrus that results in Asian citrus greening or Huanglongbing disease.
An early symptom of HLB in citrus is the yellowing of leaves on an individual limb or in one sector of a tree's canopy. Leaves that turn yellow from HLB will show an asymmetrical pattern of blotchy yellowing or mottling of the leaf, with patches of green on one side of the leaf and yellow on the other side. As the HLB disease progresses, the fruit size becomes smaller, and the juice turns bitter. The fruit can remain partially green and tends to drop prematurely.
Treatment combinations of Flg polypeptides with their retro-inverso (RI) forms can be used to minimize the effect on citrus fruit greening. Such treatment combinations can be applied on HLB-infected trees. The retro-inverso forms will compete with the native forms of Flg polypeptides for binding to the FLS-associated receptor(s) at the plant surface and thus inhibit/delay the symptom formation of greening associated with HLB disease. The native Flg22 and RI Flg22 combinations assist with a fine tuned immune response to reduce and even eliminate the disease-causing bacteria, Candidatus Liberibacter asiaticus, while preventing acute symptom development, such as leaf yellowing and citrus fruit greening.
EXAMPLESThe following non-limiting examples are provided to further illustrate the present invention.
Example 1: Application of Bt.4Q7Flg22 and Retro-Inverso Bt4Q7Flg22, and Ec.Flg22 and Ec. RI Flg22 to CornThe effect of Bt.4Q7Flg22 (SEQ ID NO: 226) and retro-inverso Bt.4Q7Flg22 (SEQ ID NO: 376), as well as Ec. Flg22 (SEQ ID NO 526) and Ec. RI Flg22 (SEQ ID 527) bioactive priming polypeptides on corn (BECK'S 5828 YH, 6175YE) yield was determined in 10 separate locations in the US Midwest (
Field seed beds at each location were prepared using conventional or conservation tillage methods for corn plantings. Fertilizer was applied as recommended by conventional farming practices and remained consistent between the US Midwest locations. Herbicides were applied for weed control and supplemented with cultivation when necessary. Four-row plots, 17.5 feet (5.3 meters) long were planted at all locations. Corn seed was planted 1.5 to 2 inches (3.8 to 5.1 cm) deep, to ensure normal root development, at 28,000 to 36,000 plants per acre with row widths of 30 inch (76.2 cm) rows with seed spacing of approximately 1.6 to 1.8 seeds per foot. Each hybrid was grown in at least three separate plots (replicates) at each location to account for field variability.
Native Bt.4Q7Flg22 bioactive priming polypeptide (SEQ ID NO: 226) and its retro-inverso polypeptide (SEQ ID NO: 376) were chemically synthesized via solid phase peptide synthesis and formulated at 0.33 Fl. oz/Ac (24.1 mL/hectare, Ha) use rate. The final concentration in the spray tank was 25 nM after dilution in carrier rate of 10 gallons water/Ac (37.85 L/Ha). Native Bt.4Q7Flg22 bioactive priming polypeptides were applied during first and second year field trials to measure effects across a multi-year growing season. Retro-inverso polypeptides were applied during the first year field trials to compare with native Bt.4Q7Flg22. Bioactive priming polypeptides were applied as foliar spray applications at 0.33 Fl. oz/Ac (24.1 mL/Ha) use rate during the V5-V8 development stage. Each polypeptide was applied with a non-ionic surfactant at 0.5%. The effect of bioactive priming polypeptides was measured as the absolute changes in yield in bushels per acre (Bu/Ac). Additionally, the win rate was calculated: the percentage of testing locations at which one treatment has a yield advantage over other treatments (in this case, as compared to the non-treated control plants).
The second year field trials were conducted using large acre field trials at 10-11 locations in the US MidWest (IL, IN, IA) and employed foliar spray application of the Bt.4Q7Flg22 bioactive priming polypeptide (SEQ ID NO: 226) provided to V8 corn plants (Dekalb 5064). Foliar spray application of Bt.4Q7Flg22 was applied at a use rate of 0.33 fluid ounces per acre (Fl. oz/Ac). As shown in
First year field trials using foliar treatments using Bt.4Q7Flg22 bioactive priming polypeptide (SEQ ID NO: 226) applied to corn hybrid (BECK's 5828 YH) shown in
A third study was performed with Bt.4Q7 Flg22 bioactive priming polypeptide tested as a V5-V8 application to corn at 3 rates and applied with a non-ionic surfactant. The final use rates were 0.33 Fl. oz/Ac, 4 Fl. oz/Ac, 8 Fl. oz/Ac (24.1 mL/Ha, 292.3 mL/Ha, 584.6 mL/Ha), resulting in approximate final concentrations of 25 nM, 300 nM, 600 nM respectively. Each study was performed at between 10 and 11 sites. The end results of the study at V5-V8 at 0.33 Fl. oz/Ac (24.1 mL/Ha) was 5.75 Bu/Ac or 360.9 kg/Ha advantage, at 4 Fl. oz/Ac a 3.77 bu/Ac or 236.6 kg/Ha advantage, and at 8 Fl. oz/Ac a 5.05 Bu/Ac or 317 kg/Ha.
Example 2: Application of Bt.4Q7Flg22 to V8 Corn with FungicideFoliar treatments with Bt.4Q7Flg22, with and without a commercially available fungicide, STRATEGO YLD, were conducted to determine if synergistic effects resulted from the combinations of the Bt.4Q7Flg22 bioactive priming polypeptide with the fungicide. Foliar spray application of Bt.4Q7Flg22 (SEQ ID NO: 226) alone or in combination with STRATEGO YLD was assessed on corn plants (hybrid Dekalb 5064) at the V8 stage of development.
Replicated trials were conducted at 6-8 locations throughout the US Midwest (IA, IL, IN) using replicated trials. Corn plants were grown as described in Example 1. Plots were maintained using the individual grower's production practices and each plot was replicated 3-4 times. When used, STRATEGO YLD fungicide (a combination of prothioconazole and trifloxystrobin) was applied using the recommended label rates (4.0 Fl. oz/Ac or 292.3 mL/Ha)) at each location. Foliar treatment applications consisted of the following treatments: (a) non-treated control, (b) STRATEGO YLD fungicide alone, and Bt.4Q7Flg22 (SEQ ID NO: 226) delivered in a free peptide form provided with (c) and without (d) the fungicide. Bt.4Q7Flg22 was applied at a use rate of 0.33 or 4.0 fluid ounces per acre (Fl. oz/Ac) or (24.1 or 292.3 mL/Ha).
Corn yield in bushels per acre (Bu/Ac) was reported at all locations as an average yield for the replicated trials at each location. The change in yield in Bu/Ac for corn plants receiving foliar applications with the STRATEGOYLD fungicide were normalized to the average yield for the control corn plants for the 6 locations (Table 22).
Foliar treatments with Bt.4Q7Flg22 provided at 0.33 Fl. oz/Ac (24.1 mL/Ha) provided yield benefits over the non-treated control corn plants with a +4.84 Bu/Ac (303.8 kg/Ha) increase observed across the 6 locations. Foliar treatment using only the fungicide application of STRATEGO YLD also provided a yield benefit in corn of +4.88 Bu/Ac (306.3 kg/Ha) over the control plants. Application of the free peptide, Bt.4Q7Flg22, at 0.33 Fl. oz/Ac (24.1 mL/Ha) combined with STRATEGO YLD fungicide at 4.0 Fl. oz/Ac demonstrated a synergistic effect, resulting in an average of +10.72 Bu/Ac (672.9 kg/Ha) over the non-treated control plants. Therefore, the Bt.4Q7Flg22 polypeptide and fungicide treatment combination resulted in a synergistic effect at the 0.33 Fl. oz/Ac (24.1 mL/Ha) use rate for the polypeptides and 4.0 Fl. oz/Ac (292.3 mL/Ha) use rate for the fungicide.
A second study looking at the combination of Ec. Flg22 with STRATEGO was also performed at 8 sites as replicated trials in the same fashion as above. Ec. Flg22 at 4 Fl. oz/Ac (292.3 mL/Ha) added 1.3 (Bu/Ac) (81.6 kg/Ha) on top of STRATEGO YLD with a 63% win percentage over 8 sites. This demonstrates that both Flg22 polypeptides were able to add benefit over a commercial fungicide, STRATEGO YLD.
Example 3: Application of Bt.4Q7 Flg22, Retro-Inverso Bt4Q7Flg22, Ec.Flg22, Retro Inverso Ec.Flg22 or RHPP to R2 Soybean—Increased YieldFoliar application using, Bt.4Q7 Flg22 bioactive priming polypeptide (SEQ ID NO: 226;
Yield results in bushels per acre (Bu/Ac) are reported for soybean grown in 11 separate US Midwest locations harvested in October (
A second study was performed to test Ec. Flg22 and Ec. RI Flg22 polypeptides as R2 foliar treatments on soybeans with a carrier rate of 10 gallons/Ac (93.5 L/Ha) water and NIS surfactant. A concentration of 100 nM was obtained in the tank for each treatment. The application of the Ec. Flg22 lead to a 0.9 Bu/Ac (60.5 kg/Ha) increase with a 82% win rate for the 11 sites, and the Ec. RI Flg22 lead to a 0.6 Bu/Ac (40.3 kg/Ha) increase with a 80% win rate over 10 sites. Also included was the RHPP polypeptide as a seed treatment, with 1.2 bu/Ac (80.7 kg/Ha) over 11 sites at 73% win rate.
A third study at the same 11 sites was performed adding a foliar fertilizer alone or with RHPP at 8 fl oz/Ac (584.6 mL/Ha). The addition of RHPP on top of the foliar fertilizer gave 1 Bu/AC (67.2 kg/Ha) advantage across the 11 sites.
Example 4: Foliar Spray Application of Flg22 Polypeptides to SoybeansFoliar treatments with Bt.4Q7Flg22, Ec.Flg22, and RHPP at 4.0 and 8.0 Fl. oz/Ac (292.3 and 584.6 mL/Ha) were tested at the R2 timing on soybean varieties over 11 sites with 10 gallons/Ac (93.5 L/Ha) water with 0.5% NIS surfactant. At the higher dose of 8 Fl. oz/Ac (584.6 mL/Ha), the Ec. Flg22 polypeptide gave a 0.74 Bu/Ac (49.8 kg/Ha) advantage and the Bt.4Q7 Flg22 gave a 0.88 Bu/Ac (59.2 kg/Ha) advantage. The lower rate of 4 Fl. oz/Ac (292.3 mL/Ha) for RHPP gave 0.31 Bu/Ac (20.9 kg/Ha) yield advantage.
Example 5: Application of Escherichia coli Flagellin Polypeptides to Increase Yield—CornThe effect of flagellin polypeptides derived from Escherichia coli on corn yield was then tested. Corn plants (Beck's 5828 YH) received an initial spray application at the V5-V8 stage of development with formulations containing the Ec. Flg22 bioactive priming polypeptide (SEQ ID NO: 526) and the retro-inverso RI Ec.Flg22 (SEQ ID NO: 527) from Escherichia coli applied at a use rate of 0.33 Fl. oz/Ac (24.1 mL/Ha). Yield results in bushels per acre (Bu/Ac) were determined for corn grown in the 12 separate locations harvested in October.
Soybean to Increase Plant Height
Foliar application of the Ec.Flg22 (SEQ ID NO: 526) and retro inverso RI Ec.Flg22 (SEQ ID NO: 527) was applied to soybean (Beck's 297NR). Plants were grown in an environmentally controlled growth room. Seed was planted directly into 39.7 cm3 pots containing Timberline top soil at a depth of 2.54 cm, with 2 seeds per pot. After planting, 50 mL of room temperature water was added to each pot to allow for germination. The pots were kept in an artificial lighted growth room receiving approximately 300 μmol m−2 s−1 (light photons) for a 13/11 light/day cycle and a 21° C. day/15° C. night temperature range. Plants received the same watering and fertilizer regimes.
Foliar treatments using both the native and retro inverso forms of Ec.Flg22 were applied to 3-week-old soybean plants at the V2 to V3 stage of development using a use rate of 0.33 Fl. oz/Ac (24.1 mL/Ha). Plant height (cm) was measured just prior to the foliar application delivered at 3 weeks and then again 2 weeks later when the plants were 5-weeks-old. Two replicate trials were conducted using 18 plants per trial.
As described in Table 23, foliar application of the Ec.Flg22 polypeptide to soybean at the V2-V3 stage of development increased plant height, compared to the control (water only treatment) plants (Table 23). Foliar application using the Ec.Flg22 (SEQ ID NO: 526) and the retro-inverso Ec.Flg22 (SEQ ID NO: 527) bioactive priming polypeptides resulted in +13% and +16% increases in plant height when normalized to the control non-treated soybean plants (normalized to 100%).
Corn (Beck's hybrid 5828 YH) plants were grown in an environmentally controlled growth room as described in Example 6. Plants were measured three weeks after emergence and then treated with foliar applications of natural (L) and retro-inverso (D) forms of Flg22 polypeptides from Bacillus thuringiensis (Bt.4Q7Flg22, SEQ ID Nos 226 and 376) and Escherichia coli (Ec.Flg22, SEQ ID NOs: 526-527). Bioactive priming polypeptides were applied as free polypeptides at a concentration of 1 μM. Control plants were treated with water alone. After an additional 2 weeks of growth, plant height was measured (at 5 weeks).
The change in plant height (Δ height cm) between the 2 week and 5 week interval time points was measured and normalized to the growth of water-treated control plants. Three replicate trials were conducted using 9 plants per trial equaling a total of 27 measurements per treatment (Table 24). There were no differences in the plant height measured between the EcFlg22, the Bt.4Q7Flg22 or the water treated control plants at the 3-week measurement time point. The greatest change in plant height from 3 to 5 weeks was reported for corn plants that received the Ec.Flg22 foliar application (Δ=17.60 cm). These plants also achieved a +8.3% increase in height compared to control plants at the 5 week measurement mark. The two retro inverso polypeptides (RI Ec.Flg22 and RI Bt.4Q7Flg2) and the natural Bt.4Q7Flg22 similarly increased plant height when compared to the control treatment with increases reported from approximately +2% to +4%.
Abiotic stress causes significant crop loss and can result in major reductions in crop production and yield potential. The flagellin compositions and flagellin-associated bioactive priming polypeptides can be used as chemical priming agents to increase tolerance of a plant to one or more abiotic stresses. Foliar treatments using the Ec.Flg22 and Bt.4Q7Flg22 and the retro inverso (RI) forms of both of these bioactive priming polypeptides were conducted to determine if these foliar applied polypeptides could provide a protective advantage against heat and drought stress.
Corn (Beck's hybrid 5828 YH) seed was planted and grown as described in Example 6 with the difference that a 16 hour day/8 hour night light-cycle was followed. Temperature was cycled from 21° C./day to 15° C./night with 75% humidity. The light cycle still provided a uniform approximately 300 μmol m−2 s−1, adequate light for plant growth. Plants were measured at 3 weeks after emergence and were then treated with foliar applications of natural or the retro-inverso (RI) forms of Ec.Flg22 (SEQ ID NOs 526-527) or Bt.4Q7Flg22 (SEQ ID NOs: 226 and 376) at 1 μM concentrations. Control plants were treated only with water. A week after the spray treatments were applied, the plants were subdivided into 2 groupings where one group remained in the same standard growth environment as described and the other group was transferred to an environment that provided heat and water deficit stress. In the heat stress environment, the temperature was elevated using heat maps from 21° C. to 27° C. for 18 hours per day for a period of 5 days. Plants were left un-watered for the heat stress duration to further simulate a water deficit stress. Change in plant height (cm) was measured 2 weeks later at 5 weeks and reported as a percentage of the height of the control (water) plants. Measurements are reported as the combined average of two trials with 9 replicate plants per trial (Table 25).
As shown in Table 25, both natural forms of the bioactive priming polypeptides (Ec.Flg22 and Bt.4Q7Flg22) increased plant growth, as measured by control plant height, when applied under non-stressed conditions. The two treatments resulted in plants that reached heights 103% and 108% of their respective controls. However, only corn plants treated with the retro inverso Flg22 polypeptides (both retro inverso Ec.Flg22 and Bt.4Q7Flg22) showed enhanced plant growth compared to control plants when grown in both normal and heat/water stressed environments. Plants treated with Ec. Flg22 Retro inverso reached 103% of their control heights in both conditions. Plants treated with Bt.4Q7Flg22 reached 102% and almost 108% of their counterpart control's heights in non-stressed and stressed conditions, respectively.
Therefore, corn plants that were treated with the retro inverso Flg22 polypeptides (RI-Ec.Flg22 and RI-Bt.4Q7Flg22) exhibited increased growth as indicated by increased percentage in plant height over the control plants. This result suggests that the retro-inverso forms are more stable in form and able to survive without proteolytic breakdown in harsher environments or situations conducive to abiotic stress. Thus, they may offer a protective advantage to plants that are subjected to abiotic stress environments.
In a separate experiment, corn plants, grown as described in Example 8, were treated with Bt.4Q7Flg22 along with a surfactant before exposure to heat and water deficit stress. Three replicate trials of 18 corn plant replicates per trial were grown in an environmentally controlled growth room until the V2-V3 stage of development. Each plant was treated with foliar sprays containing 0.1% surfactant with or without Bt.4Q7Flg22 (1 μM final concentration). A week after the spray treatments were applied, the plants were transferred to an environment that provided a heat stress and water deficit stress. Heat stress was applied using heat mats to raise the temperature in the environment from 21° C. to 27° C. During the period of heat stress, the plants were left unwatered. The corn plants remained in the simulated abiotic stress environment for one week and then plant height (cm) was re-measured (Table 26).
As shown in Table 26, in two out of the three trials, application of Bt.4Q7Flg22 polypeptide applied as a foliar spray (Trials 1 and 3) resulted in significant increased growth (height measured in cm) in corn plants as compared to the control plants treated with the surfactant alone. Foliar treatment with the Bt.4Q7Flg22 bioactive priming polypeptide resulted in an almost 13% increase in plant height in Trial 1 and more than a 33% increase in Trial 3 compared to the control (surfactant alone treated) plants.
Corn seed from two separate hybrids (hybrid BECK's 5828 AM and 4606 P2) was treated with Bt.4Q7Flg22 (SEQ ID NO: 226) bioactive priming polypeptides with final slurry concentrations of 0.25 μM or 1.0 μM (Table 27) applied to the surface of each seed. The seed applications were provided using a 40 μM polypeptide stock diluted to the appropriate concentration in a slurry containing a fungicide, insecticide, beneficial bacteria, colorant and seed finisher (EverGol Energy (0.031 mg ai/seed), PONCHO/VOTiVO (0.6 mg ai/seed), Peridium 1006 (5 fl oz/cwt or 147.9 mL/cwt) and Pro-Ized Red Colorant (normal) (0.5 fl oz/cwt). Seed treatment was applied using a Wintersteiger HEGE II (Wintersteiger AG, Austria, Germany).
Seed was planted in 12 locations in the U.S. Midwest (IA, IL, IN). Sixteen randomized replicate blocks were harvested per each of the Flg22 polypeptide treatments consisting of Bt.4Q7Flg22 applied at 0.25 μM and 1.0 μM slurry concentration.
Table 27 shows that seed treatment with the Bt.4Q7Flg22 bioactive priming polypeptide applied at what would be the equivalent of a 40 μM polypeptide solution at a rate of 0.035 or 0.14 Fl. oz (2.6 or 10.2 mL/Ha) of polypeptide solution per unit of corn seed resulted in enhanced yield with averages of +2.1 Bu/Ac (131.8 kg/Ha) increases for the low rate and +5.3 Bu/Ac increases for the high rate application as compared to non-treated control seed (no seed treatment).
A second study was set up to test the ability of Ec.Flg22, Ec.RI Flg22, Bt.4Q7Flg22, and Bt.4Q7R1 Flg22 to promote yield in corn. Replicated trials with 12 locations were set up as above. The Bt.4Q7 Flg22 gave 2.8 bushels or 71.1 kg at 50% win rate, the Bt.4Q7 RI Flg22 polypeptide gave 0.5 Bu/Ac. The Ec. Flg22 polypeptide gave 2.8 Bu/Ac (175.8 kg/Ha) advantage at 70% win rate, and the Ec. RI Flg22 gave no benefit.
A third study was set up to look at soybean seed treatment benefits of Bt.4Q7 Flg22, RI Bt.4Q7Flg22, Ec.RI Flg22, and RHPP as a seed treatment on soybean. Over a 12 location study, the RHPP polypeptide gave 0.4 Bu/AC (26.9 kg/Ha) at 64% win rate, the Bt.4Q7 Flg22 polypeptide gave 1.3 Bu/Ac (87.4 kg/Ha) at 64%, the Bt.4Q7 RI Bt.4Q7Flg22 polypeptide gave 0.3 Bu/Ac (20.2 kg/Ha) at 55%, and the Ec. RI Flg22 gave 1.8 Bu/Ac (121.1 kg/Ha) at 73% win rate.
Example 11: Application of Flagellin Bioactive Priming Polypeptides to Tomatoes—Increased YieldFoliar application treatments of Bt.4Q7 Flg22 (SEQ ID NO: 226) and Ec. Flg22 (SEQ ID NO: 526) were applied as an exogenous spray at the pre-bloom stage and used to increase yield in tomatoes.
Small scale plots were designed to simulate commercial growing conditions for tomatoes. Two hybrids of tomatoes, JetSetter (Trial 1) and Better Big Boy (Trial 2) were started as transplants in the greenhouse 42 to 56 days prior to planting in the raised field beds. Tomatoes were transplanted once soil temperatures three inches (7.6 cm) beneath the soil surface reach 60° F. (15.5° C.). Tomatoes were grown on raised beds covered with black plastic mulch. Plants were grown using drip irrigation and fertilizer applied following grower guidelines throughout the growing season to ensure optimum plant growth and yields. Small raised bed plots were designed to simulate the planting densities used by commercial growers that generally plant 2,600 to 5,800 plants per acre in single rows with 18 to 30 inches (46 to 76 cm) between plants in the row on 5- to 6.5-ft (1.5 to 2 m) centers.
Foliar treatments of Bt.4Q7 Flg22 and Ec. Flg22 at low and high use rates of 1 Fl. oz/Ac (73.1 mL/Ha) and 20 Fl. oz/Ac (1461.5 mL/Ha), respectively, were applied on the two hybrids at early bloom (first flower) stage. Replicated trials were conducted at the University of Missouri (Columbia, Mo.) in July. Control plants were treated with equal volumes (use rates) of water. Effects of the foliar treatments on increasing yield in tomatoes were determined and reported as normalized to the water control treatment. The average percentage change in yield over the average control yield is reported in the Table 28.
Foliar application of both the Bt.4Q7Flg22 and Ec.Flg22 bioactive priming polypeptides increased tomato fruit yield for each hybrid at both the low and high use rate. When results for the two hybrids were averaged, low and high application use rates for Bt.4Q7 Flg22 increased tomato yield+25% and +17%, respectively, over the control plants. Similarly, low and high application use rates for the Ec. Flg22 treatments resulted in an average increase in tomato yield of +43% and +46% over the control plants for the two hybrids.
In another experiment, tomato plants (hybrid: Better Boy), cultivated as described in the previous example, were treated with a formulation of Bt.4Q7 Flg22 at the first bloom stage. The formulation used consisted of the retro inverso D RI Bt.4Q7 Flg22 applied with 0.01% (v/v) non-ionic surfactant. The formulation was applied to tomato foliage using application use rates of 1 Fl. oz/Ac (73.1 mL/Ha) in two replicate winter tomato trials conducted in Florida. At harvest, the yield was measured as the number of fruits per plant, the weight (grams) per fruit and the total yield (lbs/Ac). Table 29 reports the yield as a percent comparison or change to the non-treated control (water only) plants.
Foliar treatment using the Bt.4Q7 Flg22 formulation applied at 1 Fl. oz/Ac (73.1 mL/Ha) increased yield of Better Boy tomatoes an average of 21% compared to the non-treated (water alone) control plants. This increase for Better Boy tomatoes corresponded to both an increase in number of fruits per plant and an increase in the fruit weight (Table 29).
Foliar treatments of Bt.4Q7 Flg22 (SEQ ID NO: 226) and Ec.Flg22 (SEQ ID NO: 526) were applied as an exogenous spray at the first-bloom stage and used to increase yield in two pepper varieties.
Foliar treatments of Bt.4Q7 Flg22 and Ec.Flg22 bioactive priming polypeptides were applied using small scale plots designed to simulate commercial growing conditions for peppers (Capsicum). Two varieties of pepper: Red Knight (RK) and Hungarian Hot Wax (HHW) were grown from 6-week old transplants in raised beds covered with black plastic mulch that had good water-holding characteristics and a pH of 5.8-6.6. Plants were grown using drip irrigation and fertilizer applied following grower guidelines throughout the growing season to ensure optimum plant growth and yields. Small raised bed plots were designed to simulate the planting densities used by commercial growers that generally plant approximately 10,000-14,000 plants per acre in double rows 14-18 inches (35.6 to 46 cm) apart on plastic mulched beds with 16-24 inches (40.6 to 61 cm) between plants in the row and with the beds spaced 5.0-6.5 feet (40.6 to 70 cm) apart from their centers. A single row of peppers also can be planted on each bed (5,000-6,500 plants per acre or 12,355-16,062 plants per hectare).
Foliar applications with compositions containing Bt.4Q7 Flg22 and Ec.Flg22 were applied at the first flower stage at an application use rate of 1 Fl. oz/Ac (low rate) or 73.1 mL/Ha and 20 Fl. oz/Ac (high rate) or 1461.5 mL/Ha on both pepper plants and compared to the control (water applied at same use rate). Effects of the foliar applications on pepper yield were determined for two separate harvests using a once over harvest approach and normalized to the yield of the control plants. The average percentage change in yield for each treatment over the yield for the control plants is reported as pounds/acre (lbs/Ac) in Table 29.
Foliar treatment of peppers using either the Bt.4Q7 Flg22 or Ec.Flg22 bioactive priming polypeptides resulted in overall average increases in pepper yield (lbs/Ac) with both the low and high application use rates and for both the RK and HHW pepper varieties. The combined yield averages for the RK and HHW varieties were +53% higher (low rate: 1 Fl. oz/Ac or 73.1 mL/Ha) and +25% higher (high rate: 20 Fl. oz/Ac) for Bt.4Q7 Flg22 foliar treated peppers compared to the control pepper plants. Alternatively, the combined yield average increases for the RK and HHW varieties were +30% higher (low rate: 1 Fl. oz/Ac) and +47% higher (high rate: 20 Fl. oz/Ac or 1461.5 mL/Ha) for Ec. Flg22 foliar treated peppers compared to the control pepper plants.
Differences existed in how the two pepper varieties responded to the foliar treatments and in the resultant yield advantages provided to both pepper varieties (Table 30). Substantial yield increases were seen in the HHW variety as compared to the RK variety of peppers and the control or non-treated plants with yield increases of +77% (low: 1 Fl. oz/Ac or 73.1 mL/Ha) and +42% (high: 20 Fl. oz/Ac or 1461.5 mL/Ha) over the control or non-treated pepper plants for the Bt.4Q7Flg22. Additionally, low use rates of the Bt.4Q7Flg22 (1 Fl. oz/Ac) and high use rates of the Ec. Flg22 (20 Fl oz/Ac) polypeptides were the most effective at increasing yield in the HHW variety (both yielded a +72% increase over the control plants).
Foliar treatment of Bt.4Q7Flg22 were applied exogenously on Ambassador squash at the first bloom stage using two separate formulations (formulation 1=F1 and formulation 2=F2). Formulation 1 (F1) consists of the native L Bt.4Q7 Flg22 bioactive priming polypeptide applied with 0.01% (v/v) non-ionic surfactant. Formulation 2 (F2) consists of the D RI Bt.4Q7 Flg22 applied with 0.01% (wv) non-ionic surfactant. Both formulations F1 and F2 were applied to squash foliage using application use rate of 1 Fl. oz/Ac (73.1 mL/Ha). Yield comparisons were made between the plants treated with the foliar Bt.4Q7Flg22 F1 and F2 spray applications compared to the control (water) or non-treated squash plants. Squash plants were cultivated in sandy loam soil as follows. 2.5 cm holes were cut in 2.5 ft. (0.76 m) wide plastic covered mounds, two rows per mound, holes spaced 1.5 ft (0.46 m) apart within each row. Rows were staggered within the mound. Mounds were spaced 4 ft (1.2 m) apart. Three squash seeds were planted per hole and thinned to a single plant per hole 14 days after planting. Drip irrigation tubing was laid in the center of each mound, and plants were watered as necessary.
Squash plants were grown from seed in raised beds until bloom, and foliar treated in the same Florida (FL) location using two replicated trials or two separate harvests. Yield for the foliar Bt.4Q7Flg22 applied F1 and F2 treated plants is reported as the number of squash per plant, the weight (grams) per squash and the total squash yield (lbs/Ac) and represented as a percentage change as compared to non-treated control plants (Table 31).
Foliar treatments of Bt.4Q7Flg22 using the two formulations F1 and F2 resulted in an increased yield advantage when foliar applied on squash (Ambassador) at the pre-bloom stage compared to the non-treated control plants. The number of squash per plant, weight per squash and overall average percent change in yield (lbs/Ac) all were increased in the Bt.4Q7Flg22 F1 and F2 treated plants compared to the control or non-treated plants. The squash plants treated with both the Bt.4Q7Flg22 F1 and F2 formulations had similar trend increases in the number of squash per plant, weight per squash and overall average percent change in yield (lbs/Ac), however squash plants that received the F1 foliar application showed increases in the number of squash per plant and in the total yield of squash over the plants that received the F2 formulation.
Codon usage was performed to generate mutations in the Bt.4Q7Flg22 to better match the host organism and the binding of the Flg22 polypeptide to the FLS receptor at the plant cell surface. A probabilistic approach was used to generate three variants of the native Bt.4Q7Flg22 that were designed to have preferred amino acid signatures for corn and soybean and to perform equal to or better than the native Bt.4Q7Flg22 (SEQ ID NO: 226) in ROS activity assays. These variants possessed mutations to the internal segment (SEQ ID NO: 571), or the C-terminus (SEQ ID NO: 572) or the N terminus (SEQ ID NO: 573) and were designated as Bt.4Q7Flg22-Syn01, Bt.4Q7Flg22-Syn02 and Bt.4Q7Flg22-Syn03, respectively. Bt.4Q7Flg22-Syn01 and Bt.4Q7Flg22-Syn03 were then measured in relation to their native forms at a variety of concentrations.
Fresh plant tissues from corn (hybrid 5828 YX) and soybean (hybrid 297 R4) leaves were cut into uniform samples and floated on 150 μL of sterile water in a 96-well white, low luminescence plate. The plate was placed under growth lights that had a 16-hour light/8-hour dark cycles at a consistent temperature of 22° C.
For corn samples, aerial tissue from V1 to V4 stage corn plants was cut away from the plant above the soil line using a clean razor blade. The cotyledon and sheath were removed. 1-mm slices were cut through the stalk from the base of the plant until approximately 1.3 cm below the first leaf node. Each corn section was placed in an individual well of the 96-well plate.
For soybean samples, fully expanded trifoliate leaves were removed from V1-V3 stage plants. Leaf discs (12.6 mm2) were cut from the leaf blades using a 4-mm diameter clean, sharpened cork borer. Discs were cut in half using a clean razor blade, and each disc half was placed in an individual well of the 96-well plate.
Native Flg22 polypeptide (SEQ ID NO: 226) or Flg22 polypeptides containing the described mutations (SEQ ID NOs 571 or 573) stocks were prepared in either sterile, deionized water or 100 mM sodium phosphate (pH 7.8-8.0) buffer with 0.1% Tween-20. After 18-24 hours, the water was removed from each well of the 96-well plate. Plant tissue samples were treated with a 100 μL elicitation solution containing 1:100 dilution of Flg22 polypeptide stock (concentration range from 250 picomolar (pM) to 10 micromolar (μM)), 34 μg/mL luminol, and 20 μg/mL horseradish peroxidase. Recognition of the Flg22 polypeptide by the plant tissue resulted in activation of immune signaling and the production of apoplastic reactive oxygen species (ROS). In the presence of ROS (H2O2), horseradish peroxidase catalyzed the oxidation of luminol and production of visible light. Relative light units (RLUs) were recorded with a GLOMAX 96 microplate luminometer (Promega Corporation) using a 0.5 s integration; 2.6 min intervals over a time course of 40 minutes.
For data analysis, total RLUs produced were calculated for each sample over the entire 40 min time course. Significant outliers beyond the interquartile range were excluded from analysis. Total RLUs in each condition (n=6-16) were normalized to the average RLU for Bt.4Q7Flg22 at 25 nM and reported as a percentage (%) of the Bt.4Q7Flg22 control (Table 32).
The synthetic mutagenized Bt.4Q7Flg22-Syn01 version had increased ROS activities at a range of concentrations (0.25-100 nM) while Bt.4Q7Flg22-Syn03 was more varied and showed increased ROS activities at 0.25 nM, 1 nM, 10 nM, 25 nM, and 100 nM concentrations as compared to the native version of Flg22 or Bt.4Q7Flg22. The synthetic version of Bt.4Q7Flg22-Syn01 treatment using 5 nM resulted in the largest change in ROS activity over the native version or Bt.4Q7Flg22. ROS activities for Bt.4Q7Flg22-Syn03 showed a more varied response over the range of concentrations added.
Based on the results from preliminary studies in Example 15, the following concentrations were chosen to screen ROS activities of a wide range of Flg22 polypeptides in corn and soybean: 5 nM in corn (hybrid 5828 YX) and 100 nM in soybean (hybrid 297 R4). ROS activity assays were then used to identify the best Flg22 bioactive priming polypeptide candidates for individual treatment use of corn and soybean and to identify those candidates that were active for both corn and soybean.
Corn and soybean leaf tissues were harvested from plants and ROS assays were performed as previously described in Example 15 for the mutant polypeptides listed in Table 33. Total RLUs produced were calculated for each sample over the entire 40 min time course. Significant outliers beyond the interquartile range were excluded from analysis. Comparisons of ROS activity on corn (hybrid 5828 YX) and soybean (hybrid 297 R4) were made and reported as the percentage (%) of relative light units (RLU) compared to the average RLU values at the 25 nM Bt.4Q7Flg22 treatment concentration (Table 33).
Table 33 summarizes the relative activity for a variety of mutant Flg22 polypeptides compared to native Bt.4Q7Flg22 alongside the standard deviation in for each condition (STDEV).
Based on the results from T able 33, a number of predictions could be made based on the effect of different mutations on Flg22 polypeptides on ROS activity in corn and soybean. Table 34 describes ROS activity observed or predicted for a variety of targeted mutations. Briefly, replacements at the first amino acid (D1N, D1Q or D1T) have or likely will result in strong recognition and/or activation of the Flg22 receptor in corn. Mutations in the inner segment, K7Y, K7F and A16P, will likely have similar positive results in soybean. Of the tested polypeptides, Bt.4Q7Flg22-Syn01 (S13K) and Bt.4Q7Flg22-Syn03 (D1Q) had the strongest ROS-inducing activity in corn and soybean.
Corn and soybean leaf tissues were harvested from plants and ROS assays were performed as previously described in Example 15. The relative ROS activity of different Flg22 variants, alone or in combination, were assessed to identify the preferred combinations of Flg22 polypeptides that when applied together provided the highest ROS activity response for bath corn and soybean. Results are summarized in Table 35.
Cellobiose is a glucose disaccharide and a building block for cellulose polymer. Chemically, it is glucose-beta-1-4-glucose, a reducing sugar that consists of two β-glucose molecules linked by a β (1-4) bond. Cellobiose is obtained by the breakdown of cellulose or lichenin and yields glucose upon hydrolysis. Treatments using Bt.4Q7Flg22 were compared with and without cellobiose in ROS activity assays to determine if cellobiose can act an elicitor to increase ROS production in reactions containing Flg22 polypeptide. The specific treatments conducted using ROS assays with corn (
Corn and soybean leaf tissues were harvested from plants as previously described in Example 15. Flg22 bioactive priming polypeptide stocks were prepared in either sterile, deionized water or 100 mM sodium phosphate (pH 7.8-8.0) buffer with 0.1% Tween-20. After 18-24 hours, the water was removed from each well of the 96-well plate. Samples were treated with a 100 μL solution containing Bt.4Q7Flg22 (SEQ ID NO: 226, 25 nM), cellobiose (100 μM or 1 mM), 34 μg/mL luminol, and 20 μg/mL horseradish peroxidase. Recognition of the Flg22 polypeptide by the plant tissue resulted in activation of immune signaling and the production of apoplastic reactive oxygen species (ROS). In the presence of ROS (H2O2), horseradish peroxidase catalyzed the oxidation of luminol and production of visible light. Relative Light Units (RLUs) were recorded with a GLOMAX 96 microplate luminometer (Promega Corporation) using 0.5 s integration; 2.6 min intervals over a time course of 40 minutes.
For data analysis, the average RLU per treatment (n=6-16 samples, +/−standard error of the means) was graphed over the time course (
The average RLU across the experiment for each treatment is graphed in
The effect of Phytosulfokine alpha (PSKα), a sulfonated bioactive priming polypeptide derived from Arabidopsis thaliana, on corn and soybean yield was tested. Corn and soybeans were cultivated in the field as described in Example 1 and 3. Arabidopsis thaliana PSKα (SEQ ID NO: 598) was applied at a final concentration of 1 μM in foliar spray with a surfactant and provided using a uniform application to the above ground plant parts of corn (hybrid 5140RR) and soybean (hybrid 375 NR). At.PSKα formulations were applied at the V5-V8 stage of development in corn and the V1-V4 stage of development in soybean. Corn and soybean plants treated with At.PSKα were compared to non-treated control plants (water). Treated plants were randomized at one location in four replicate blocks for comparisons to the controls. Yield was reported in Bushels per acre (Bu/Ac).
Table 36 depicts how foliar application of At.PSKα resulted in yield increases in both corn and soybean yield trials. Both corn and soybean had positive yield increases in the field with foliar formulations containing At.PSKα applied at the V5-V8 stage of development in corn and the V1-V4 stage of development in soybean. On average, corn had a +3 Bu/Ac (188.3 kg/Ha) increase in overall yield in the field and soybean had a +0.8 Bu/Ac (53.8 kg/Ha) yield increase.
A method is provided wherein applying At.PSKα as a foliar application to actively growing soybean plants provides a yield advantage in environments with heat and drought stress.
Soybean plants were grown as described in Example 6. The At.PSKα polypeptide (SEQ ID NO: 598) was applied as a foliar spray to the plants at the V1-V4 stage. Soybean plants treated with foliar applications of At.PSKα and control plants treated with water and surfactant alone were then grown in conditions described in Examples 7-9 that produced a non-stress and stress (heat and water deficit) environments. Table 37 describes the percentage change or increase in height reported for soybean plants treated with At.PSKα as a foliar spray at the V1-V4 growth stage. At.PSKα application resulted in a +3.5% increase in height in the non-stress environment and a +4.3% increase in height in stress environments reported in Bushels per acre (Bu/Ac) as compared to the non-treated control soybean plants.
Root hair promoting polypeptide (RHPP, SEQ ID NO: 600) originally derived for soybean (Glycine max) is provided as a foliar application to produce beneficial phenotypes in corn.
Native and retro inverso RHPP (SEQ ID NOs 600-601) will be applied to corn plants at the V5-V8 stages. Retro inverso RHPP may be modified with C-terminal amidation prior to application. Treatment with RHPP in this way is expected to result in a distinct leaf architecture phenotype with an upright leaf orientation and more erect leaves. The increase in leaf angle has impactful advantages for use in agriculture in this area. This is particularly relevant with higher planting densities used to maximize yield in a field environment. Foliar applications of the RHPP polypeptide in maize (corn) is useful for changing the leaf angle thus contributing to a smaller leaf angle which results in an upright leaf orientation. This phenotype can be beneficial for increasing the leaf area index, reducing maize shade syndrome, and improving photosynthetic efficiency. In addition, providing RHPP as a foliar formulation to maximize canopy development and total light penetrance is key to increasing vegetative growth of the plants prior to the initiation of the grain filling stage.
Example 23: Application of RHPP to Increase Root Biomass and Yield Parameter-SoybeanEffective nodulation of soybean roots result in higher yields and higher quality seed production, protein and oil per seed or acre basis. This could be due to increased nitrogen fixation since nodulale formation increases nitrogen fixation. To determine whether root hair promoting bioactive priming polypeptide, RHPP (SEQ ID NO: 600) could modulate root biomass and nodulation and thereby improve nitrogen fixation, soybean plants (hybrid Morsoy 38X52 and Beck's hybrid 297R4) were treated with foliar application of RHPP (300 nM) at the R1-R2 stage of development.
Increased Plant Biomass and NodulationRHPP bioactive priming polypeptide (SEQ ID NO: 600, originally derived from Glycine max) was applied as foliar treatment to 4-week-old hybrid soybean (Morsoy variety) with 0.1% (v/v) non-ionic surfactant (ALLIGARE SURFACE™) using a spray bottle and delivering approximately 1.25 ml/plant. The experiment was conducted using a total of 8 plants per trial per treatment group. The pots were kept in an artificial lighted growth room receiving a light level of approximately 300 μmol m−2 s−1 for a 16/8 light/day cycle and a 21° C. day/15° C. night temperature range. Growth parameters of nodule counts, root biomass and total biomass per plant were measured at 15 days post the foliar application and compared between the foliar treatments consisting of ALLIGARE SURFACE surfactant (0.1% v/v) as a control and the RHPP polypeptide (300 nM) containing the ALLIGARE SURFACE surfactant (0.1% v/v). Average growth parameters as described were normalized to the control plants that received the surfactant alone treatment (Table 38).
Nodulation counts on the roots of each plant treated with a foliar application of RHPP were compared to the number of nodules on the control plants treated with 0.1% (v/v) surfactant alone. RHPP treatment resulted in approximately two times the number of nodules on the roots of each soybean plant compared to control (surfactant) treatment. Soybean plants receiving the foliar application of the RHPP polypeptide also exhibited an increase in root biomass and total overall plant biomass which when normalized to the control resulted in an increase of more than 20% in root biomass and 8% in total biomass.
RHPP bioactive priming polypeptide (SEQ ID NO: 600) was also applied as foliar treatment to R1 stage hybrid soybean (Beck's 297R4) with 0.1% (v/v) non-ionic surfactant (ALLIGARE SURFACE) using a spray bottle delivering approximately 1.2 ml/plant. This experiment was performed to look at the effects of RHPP on plant growth and was conducted using a total of 18 plants per treatment group. The pots were kept in an artificial lighted growth room receiving a light level of approximately 300 μmol m−2 s−1 for a 1816 light/day cycle and a 21° C. day/15° C. night temperature range. R1 stage soybean plants were treated with nothing (non-treated control), ALLIGARE SURFACE surfactant applied at a concentration of 0.1% (v/v) or the RHPP polypeptide (300 nM) applied in combination with ALLIGARE SURFACE surfactant (0.1% v/v). Height for each plant was recorded at the time of spray and again at 16 days post foliar application and average growth parameters were compared between foliar treatments (Table 39).
Soybean plants that received the foliar application of RHPP polypeptide (300 nM+0.1% ALLIGARE SURFACE) had increased plant growth (plant height) and an increased change in plant height as compared to the plants that received the surfactant alone and non-treated control (Table 39).
The Gm.RHPP bioactive priming polypeptide (SEQ ID NO: 600) was applied as a foliar application with a liquid foliar fertilizer, N-RAGE MAX (21-1-3 N-P-K), to two soybean varieties (AG3536 and AG3832). Foliar application of RHPP was applied at 1 Fl. oz/Ac or 73.1 mL/Ha (300 nM concentration) with the recommended use rate of the fertilizer for soybeans (1 to 2 gal/Ac (9.4 to 18.8 L/Ha), or equal to Nitrogen 2.16 lbs/gal (0.29 kg/L); Phosphate P2O5 0.10 lbs/gal and soluble potash (K2O 0.31 lbs/gal or 0.4 kg/L). Foliar application of the combination RHPP, fertilizer treatment was provided to two soybean varieties (AG3536 and AG3832) at the R2 stage (recommended stages R1 to R6) of development in 5 locations across the US Midwest (IA, IL, IN). Foliar application of Gm.RHPP with the N-RAGE MAX provided a yield advantage of 1.9 Bu/Ac (127.8 kg/Ha) compared to the control treatment and on average a 1.4 Bu/Ac (94.2 kg/Ha) increase compared to those plants that received the fertilizer alone treatment for variety 1 (AG3536) (Table 40).
Foliar application treatments of Gm.RHPP (SEQ ID NO: 600) was applied as an exogenous spray at the pre-bloom stage and used to increase yield in tomatoes. Two tomato hybrids (JetSetter and Better Big Boy) were planted in small scale plots as described in Example 12. Foliar treatment of Gm.RHPP was applied at an application use rate of 1 Fl. oz/Ac (73.1 mL/Ha) and 20 Fl. oz/Ac (1461.5 mL/Ha) to the two hybrids, JetSetter (Trial 1) and Better Big Boy (Trial 2), at early bloom (first flower) stage. Replicated trials were conducted at the US Midwest (Missouri) in July. The foliar treatment of Gm.RHPP on tomato plants was compared to the control (water applied at same use rate). Effects of the foliar treatments on increasing yield in tomatoes were determined and reported as normalized to the water control treatment and reported as the average percentage change in yield over the average control yield in Table 41.
The average yield represented as a percent change over the control plants was reported separately for the two trials and as the average for the two tomato hybrids. Foliar application using Gm.RHPP resulted in an increase in tomato fruits for each of the two trials when applied at a use rate of 1 Fl. oz/Ac (73.1 mL/Ha). Application of Gm.RHPP resulted in an average increase in tomato yield of +52% over the control plants for the two hybrids with individual average increases of +93% for the Jetsetter hybrid and +10% for the Better Big Boy compared to the control plants.
Foliar treatment of Gm.RHPP (SEQ ID NO: 600) was applied as an exogenous spray at the first-bloom stage to increase yield in two pepper varieties. Foliar treatment of Gm.RHPP was applied using small scale plots designed to simulate commercial growing conditions for peppers (Capsicum) as described in Example 13. Foliar applications with the Gm.RHPP bioactive priming polypeptide were applied at the first flower stage, on two varieties of pepper, Red Knight (RK) and Hungarian Hot Wax (HHW). The foliar Gm.RHPP treatments were applied using an application use rate of 1 Fl. oz/Ac (73.1 mL/Ha) on the RK and HHW pepper plants and compared to the control (water applied at same use rate). Effects of the foliar applications on pepper yield were determined for two separate harvests using a once over harvest approach and normalized to the yield of the control plants. The average percentage change in yield over the yield for the control plants is reported in Table 42, as the percent change per total weight (lbs/Ac) of peppers harvested. Average percent change in yield is reported for the 2 replicate harvests (trials) for the RK and HHW pepper varieties and then as a combined average for both varieties.
Percent average yield for RK and HHW peppers that received the Gm.RHPP applied at the use rate of 1 Fl. oz/Ac (73.1 mL/Ha) was increased by 87% for RK and 46% for HHW peppers compared to the control plants. The combined average for both pepper varieties was reported as an average 67% increase for the percent change in yield in the foliar Gm.RHPP treated peppers over the non-treated (water) control pepper plants (Table 42).
Example 27: Application of Harpin-Like and ALPSKα Polypeptides to CornHarpins can provide functional benefits when applied both exogenously, for example as a foliar spray to the plant surface, or provided apoplastically (the space outside of the plant cell membrane) or endogenously (inside a plant cell/plant cell membrane). Synthetic harpin bioactive priming polypeptide, HpaG-like (Xanthomonas spp., SEQ ID NO: 587) was applied exogenously to the surface of corn plants at the V2-V3 stage of development. Additionally, the effect of exogenous application of Phytosulfokine alpha (PSKα), a sulfonated bioactive priming polypeptide derived from Arabidopsis thaliana, on corn growth was tested.
Corn (Beck's hybrid 5828 YH) plants were grown in an environmentally controlled growth room. Corn seed was planted directly into 39.7 cm3 pots containing Timberline top soil at a depth of 2.54 cm, with 2 seeds per pot. After planting, 50 mL of room temperature water was added to each pot to allow for germination. The pots were kept in an artificial lighted growth room receiving approximately 300 μmol m−2 s−1 (light photons) for a 16/8 light/day cycle and a 21° C. day/15° C. night temperature range. Plants received the same watering and fertilizer regimes.
Plant height (cm) was measured at 3 weeks after emergence. Bioactive priming polypeptides for HpaG-like (SEQ ID NO: 587), provided as a synthetic 23 amino acid polypeptide, and At.PSKα (SEQ ID NO: 598) were then applied to the corn plants as a foliar spray at final concentrations of 1 μM for HpaG-like and 100 mM for PSKα bioactive priming polypeptides. Control plants were treated with surfactant (0.01% v/v) alone. A week after the spray treatments were applied, the plants were subdivided into 2 groupings where one group remained in the same standard growth environment described above and the other group was transferred to an environment that provided heat and water deficit stress. For the heat and water deficit treatments, the growth room environment (with the exception of temperature and watering/fertilizer cycles) remained similar to the standard growth environment). Heat stress was applied using heat mats to raise the temperature in the environment from 21° C. to 27° C. During the period of heat stress, the plants were left unwatered to simulate a water deficit stress. Change in plant height (cm) was measured at 5 weeks and reported as normalized to or as a percentage of the height of the control (water) plants. Measurements are reported as the combined average of two trials with 9 replicate plants per trial (Table 43) and are presented as a percentage of growth over control corn plants that received water plus surfactant (0.01% v/v) standardized to measure 100% (Table 43).
Foliar application using the HpaG-like polypeptide showed an improved growth phenotype in normal environments, but not stressed environments, when compared to the control plants, while foliar application of PSKα exhibited an improved growth phenotype when grown under conditions of heat and water deficit stress but not in the non-stressed environment.
In a separate set of replicated trials, similar changes in growth rates resulted from the foliar applications of HpaG-like (SEQ ID NO: 587) and PSKα (SEQ ID NO: 598). Table 44 shows the percentage change in plant growth for corn receiving X. spp. HpaG-like polypeptide (1 μM final concentration) and At.PSKα (100 nM final concentration) applied as foliar treatments and measured by changes in plant height compared to control (water plus 0.01% v/v surfactant) plants grown in optimal (non-stress) and in stress environments. This suggests that the combined foliar application or sequential applications of PSKα with HpaG-like bioactive priming polypeptides may be useful for enhancing growth of plants growth under standard (non-stress or optimal growth) environments or of plants exposed to abiotic stress (for example, heat, and water deficit stress).
The bioactive priming polypeptides, Bt.4Q7Flg22 and Ec.Flg22, were combined with RHPP and accessed for yield benefits in soybean. The combination of either Bt.4Q7Flg22 (SEQ ID NO: 226) or Ec.Flg22 (SEQ ID NO: 526) and RHPP (SEQ ID NO: 600) were foliar applied to two varieties of soybean (AG2836, Variety 1; AG3536, Variety 2) in 7 locations across the US Midwest (IA, IL and IA).
Foliar application using Bt.4Q7 Flg22 bioactive priming polypeptide (SEQ ID NO: 226;
Soybean variety AG3536 (Variety 2) consistently outperformed AG3536 (Variety 1) for yield Bu/Ac in all 7 locations across the US Midwest. Foliar applications with the Bt.4Q7Flg22, Ec.Flg22 and RHPP applied individually at the 3 different use rates (0.33, 4.0 and 8.0 Fl. oz/Ac) or (24.1 mL/Ha, 292.3 mL/Ha, 584.6 mL/Ha) all resulted in a yield advantage over the non-treated control plants. The RHPP applied foliarly using a 4.0 Fl. oz/Ac (292.3 mL/Ha) use rate resulted in the largest yield increase of +1.26 Bu/Ac (84.7 kg/Ha) over the control plants compared to the other bioactive priming polypeptides applied separately. However, the combination of Bt.4Q7Flg22 with RHPP provided an additional yield advantage resulting in a +2.61 Bu/Ac (175.5 kg/Ha) over the non-treated soybean control plants. This increase in yield seen from soybean plants treated with foliar applications of Bt.4Q7Flg22 combined with RHPP illustrates a synergistic effect achieved by combining the bioactive priming polypeptides where the increase in yield of the combination was greater than the sum of the two polypeptides applied separately.
Example 29: Use of Agrobacterium tumefaciens to Test Effectiveness of Thionins in Treating HLB DiseaseAgrobacterium tumefaciens strain GV3101 was inoculated into Luria broth medium (LB) and grown for 20 hours. Initially the optical density (OD) of the culture was measured at a wavelength of 600 nm using a spectrophotometer and normalized to a low starting density. The cultures were then divided equally and treated with similar proportions of thionins that are representative of mixtures used to treat citrus trees. The ratios of Cs.thionin (SEQ ID NO: 651), As.thionin (SEQ ID NO: 652) and Mt.thionin (SEQ ID NO: 653) used were 10.0%, 2.0%, 0.40%, 0.08%, and 0.02% and were prepared to match the 20 mL total volume of filtrate of each of the thionin mixtures that is used as a treatment per tree. Each thionin mixture was also compared to control mixtures containing only: filtrate, minimal media (LB), or a tetracycline (Tet) antibiotic (10 μg/mL per culture). Each bar represents a combined OD measure of 3 replicates. After incubation with the thionin and antibiotic mixtures, the optical density (OD 600) was measured again to determine if growth of the Agrobacterum cultures was reduced or inhibited.
As is shown in
Use of thionins to treat Candidatus Liberibacter asiaticus infection will be tested in citrus trees from an orchard located in central Florida (Okeechobee county). Treatment of a total of 26 trees will use formulation mixtures of thionin (SEQ ID NO: 620; 621 and 622) either with or without a phloem localization sequence (SEQ ID NO: 611) to target the thionins specifically to the phloem where Candidatus Liberibacter asiaticus reside. Inoculation of Valencia orange (Citrus sinensis) trees with these formulations of thionins and mixtures thereof will be conducted using a low-pressure injection device, BRANDT ENTREE. Four total thionin treatments including water as a negative control and oxytetracycline as a positive control will be applied to 5 year-old trees. The citrus trees will be randomized into treatment blocks for control (non-treated), thionin treated and positive control antibiotic (oxytetracycline) treated tree plots. Thionins fused to a phloem targeting sequence will be expressed in a pBC vector, and thionin containing filtrate will be collected from the expressed cells. A total volume of 20 mL containing a mixture of thionins: Cs.thionin (SEQ ID NO: 651), As.thionin (SEQ ID NO: 652) and Ms.thionin (SEQ ID NO: 653) will be provided as 20 mL total volume of filtrate. The thionin treated citrus trees will be compared to the non-treated (control) trees and trees that received a separate positive control of an antibiotic, oxytetracycline, applied with a concentration of 2 grams/tree. Levels of infection of trees with Candidatus Liberibacter asiaticus will be confirmed by qPCR detection or amplification using 16S rRNA gene specific primers and nested primers to detect the HLB disease [Sequence 5′>>3′:(forward) HLB as TCGAGCGCGTATGCAATACG; (reverse) HLBr GCGTTATCCCGTAGAAAAAGGTAG; HLBpc (probe) AGACGGFTGAGTAACGCG labeled with fluorescein reporter dye].
Plants will be treated in March and leaf samples will be collected one month later in April. Average bacterial counts for Candidatus Liberibacter asiaticus will be assessed along with visual symptomology ranking scores for leaf blotch mottling or signs of yellowing of leaves and stems.
Fruit size, shape and level of fruit development or maturity will be collected for 20 representative fruits per tree. Longitudinal length (major diameter, cm) and width (minor diameter, cm, the average of the largest and smallest widths if the fruit is not symmetrical). Fruit shape will be measured by the ratio of width to length. Total fruit weight will be obtained and divided by the total number of fruits (20) to provide an average fruit weight (grams). Total fruit weight will be collected and represented in kg/tree.
Acid-corrected oBrix (oBrixc) values of juice obtained from the juiced (squeezed) grapefruit and orange fruit will be obtained per tree following the USDA minimum standards for oBrixc laboratory analytical methods. Percent acid (%, w/v) will also be measured. The oBrix reading on a refractometer for a juice to be reconstituted equals the value of the desired acid-corrected oBrix subtracted of the acid contribution and temperature effect. The total titratable acidity (% acid) of the reconstituted juice will also be calculated based on the reconstituted oBrix and Brix/Acid ratio and adjusted using an acid correction and temperature correction factors (JBT FoodTech Laboratory Manual, “Procedures for Analysis of Citrus Products, Sixth Edition).
Bacterial cell counts will be calculated using real time fluorescent PCR, quantitative polymerase chain reaction (qPCR) techniques to detect only live bacterial and subtract out background DNA including naked DNA or DNA from dead cells (Davis and Brlansky, “Quantification of live Candidatus Liberibacter asiaticus” populations using real-time PCR and propidium monoazide”, Plant Disease 97: 1158-1167, 2013). Colony counts specific for Candidatus Liberibacter asiaticus (CLas) cells will be measured in the leaves collected from the thionin treated, non-treated (control) and positive control (antibiotic) treated trees. Calculations for live bacterial titers will be obtained from the DNA yield obtained by qPCR, fit into a regression equation to correlate target copy number to total bacterial counts and represented on a log scale of live cells per gram tissue. Comparisons of titers from treated and non-treated trees will be matched with the degree of disease severity or disease symptoms, such as the classic blotchy mottling on the leaves, deformed or lopsided fruit and greening fruit, etc. for both the red grapefruit and Valencia orange trees.
Example 31: Use of Retro-Inverso Flg Bioactive Priming Polypeptides to Treat and Reduce Citrus GreeningCombinations of flagellin-associated polypeptides paired with their retro-inverso counterparts can be used to treat and reduce the greening effect on citrus that results in Asian citrus greening or Huanglongbing disease (HLB).
An early symptom of HLB in citrus is the yellowing of leaves on an individual limb or in one sector of a tree's canopy. Leaves that turn yellow from HLB will show an asymmetrical pattern of blotchy yellowing or mottling of the leaf, with patches of green on one side of the leaf and yellow on the other side. As the HLB disease progresses, the fruit size becomes smaller, and the juice turns bitter. The fruit can remain partially green and tends to drop prematurely.
The retro-inverso forms of Flg22 can compete with native forms of Flg22 for binding to the FLS-associated receptor(s) at the plant surface and thus inhibit/delay the symptom formation of greening associated with HLB disease. Using native Flg22 and RI combinations will assist with a fine tuned immune response to reduce and even eliminate the disease-causing bacteria, Candidatus Liberibacter asiaticus and thus prevent acute symptom development, such as leaf yellowing and citrus fruit greening.
Treatment combinations of Flg polypeptides with their retro-inverso (RI) forms will be used to minimize the effect of HLB infection on citrus fruit greening. Thirty-four commercial grapefruit, Citrus paradise Macfad., and six sweet orange, Citrus sinensis (L.) trees, with or without symptoms of HLB disease, will be treated using flagellin bioactive priming polypeptide combinations described in Table 46, below, using a low pressure injection device called BRANDT enTREE to distribute the Flg polypeptides into the interior of the tree.
Leaf tissue samples from these treated grapefruit and sweet orange trees will be analyzed using the ROS assay as described in Example 15. Sampling will be conducted in orchard groves from March to August in central Florida. The sample of citrus orchards will be assumed to be representative of the state. The orchard sampled will have a minimum acreage of 2 hectares (range of 2-24 Ha and an average of 5.2 Ha). Selected orchard citrus trees will be randomly selected with the non-treated control trees nested in each randomized plot. Leaf tissues from the grapefruit and orange trees will be collected from trees of approximately the same age. Leaves will be sampled at similar locations on the trees and only from trees that had a new flush of growth at the time of sampling. In the orchards selected for sampling, similar cultural practices will be maintained and include flood irrigation and weed management with herbicides. However, the selected orchards will not receive any pesticide application for a minimum of 30 days before leaf sampling for the ROS assays. Two replicate trials of 10 grapefruit trees exhibiting symptomology of HLB disease will be randomly sampled per orchard and compared to 14 grapefruit trees (non-infected control) sampled that do not exhibit any symptoms. Similar leaf sampling will be performed in sweet orange (four infected samples compared to 2 uninfected controls). Trees will be selected to be representative of the whole orchard. A nested analysis of variance (ANOVA) will be performed to determine the statistical significance of any differences in ROS activities observed from treatment of the control and infected HLB citrus leaf samples.
Example 32: Foliar Application of the Flg22 Polypeptide Reduces Cercospora Leaf Blight Disease of SoybeanFoliar application of the Bt.4Q7Flg22 bioactive priming polypeptide (SEQ ID NO: 226) derived from Bacillus thuringiensis and Bacillus pseudomycoides expressing Bt.4Q7Flg22 (H1) were applied to soybean plants (commercial hybrid Beck's 294 NR) at the V3 stage of development that were grown at 3 separate US Midwestern locations that were known to previously have Cercospora infection in the fields.
A Cercospora leaf blight rating scale (percentage of leaf area affected) was used to rate disease severity in all field experiments. The percentage of leaf area affected was calculated using a visual key based on the ASSESS image analysis for plant disease quantification (Chagas Ferreira da Silva, LSU Master's Theses, 2014). Symptom ranking as a percentage was done for the uppermost trifoliate leaves
The results are described in Table 47. Visually, soybean plants that received the foliar treatments of the Bt.4Q7Flg22 bioactive priming polypeptide and Bacillus pseudomycoides expressing Bt.4Q7Flg22 (H1) had increased vigor as compared to the non-treated control plants. The control plants showed an increase in early symptom development at the 4 week observation time point, 30% as compared to 20% with the Bt.4Q7Flg22 treatment (0.33 Fl. oz/Ac or 24.1 mL/Ha) and approximately 5% with the Bt.4Q7Flg22 treatment (4.0 Fl. oz/Ac or 292.3 mL/Ha). Soybean plants receiving the Bacillus pseudomycoides expressing the Bt.4Q7Flg22 (H1) treatment also showed less early symptom development as a result of Cercospora infection than the non-treated control plants, 20% at 4 weeks (0.33 Fl. oz/Ac or 24.1 mL/Ha) and 10% (4.0 Fl. oz/Ac or 292.3 mL/Ha). At 8 weeks post application, the non-treated control plants showed 50% visual symptom damage on the upper foliage of the plant (top 3-4 trifoliate leaves). The symptom ranking for plants that received the foliar treatments of the Bt.4Q7Flg22 polypeptide (0.33 Fl. oz/Ac or 24.1 mL/Ha) was comparable to the non-treated control plants at 8 weeks post foliar treatment. However, the soybean plants that received the foliar treatments of Bt.4Q7Flg22 polypeptide (4.0 Fl. oz/Ac) and Bacillus pseudomycoides expressing Bt.4Q7Flg22 (H1) (0.33 Fl. oz/Ac or 24.1 mL/Ha) and 4.0 Fl. oz/Ac or 292.3 mL/Ha) showed considerably less apparent symptoms and damage. Overall the treatment of the Bt.4Q7Flg22 polypeptide (4.0 Fl. oz/Ac or 292.3 mL/Ha) was effective at the prevention of early symptom development from Cercospora infection as compared to the non-treated plants that showed blight and purple coloration symptoms as well as defoliation. Therefore, foliar application of Bt.4Q7Flg22 polypeptide applied at a higher application use rate (eg. 4.0 Fl. oz/Ac or 292.3 mL/Ha)) can provide a means of managing early symptom development and provide healthier more vigorous soybean plants grown in field locations that have been impacted by Cercospora.
Enhanced Normalized Difference Vegetation Index (ENDVI) is an indicator of live, photosynthetically-active green vegetation and was used to compare the effectiveness of treatments in field trials using remote sensing technology. In the ENDVI index, values ranging from −1.0 to 0.1, are indicative of unhealthy plants with decreased photosynthesis, whereas values approaching 1 are indicative of lush greenness, high photosynthetic capacity, and increased biomass. Healthy plants strongly absorb visible light from the 400-700 nm spectral wavelength range and reflect the wavelengths in the near-infrared light from 700-1100 nm. ENDVI measurements can correspond to certain vegetative properties, such as plant biomass or greenness, absorption of light by plant canopies, photosynthetic capacity (e.g., leaf area index, biomass, and chlorophyll concentration). ENDVI images were collected using a BGNIR camera (Zenmuse X3) attached to a drone (DJI MATRICE 100) specifically created to capture images and filter different wavelengths of light during the capture. The camera uses sensors to capture visible and near-infrared bands of the electromagnetic spectrum. Healthy plants with large amounts of vegetation or biomass reflect green (G) and near-infrared (NIR) light, while absorbing both blue (B) and red light. Plants that are less healthy or that have less above-ground biomass reflect more visible and less NIR light. ENDVI uses both NIR and G as the reflective channels while using B as the absorption channel. The ENDVI formula below adds the NIR and green channels together for the reflective channel. The blue channel is multiplied by two to compensate for the NIR and G channels being added together. The ENDVI equation uses the following calculation for the NIR, G, and B channels to provide a ratio value as a single output.
Corn seed (DEKALB hybrid DKC 58-89) treated with a seed treatment comprising EVERGOL fungicide (7.18% propiconazole, 3.59% penflufen and combined with 5.74% metalaxyl) and PONCHO/VOTiVO 500 (a mixture of 40.3% clothianidin insecticide and 51.6% Bacillus firmus 1-1582, a microbial agent) was planted in the US Midwest (IL). Various foliar treatments containing Bt.4Q7Flg22 and a synthetic version of Bt.4Q7Flg22 (Syn01Flg22 as described in Table 48) were applied to corn plants at the V5-V7 stage of development. BGNIR images were collected by drone flight, 50 m above the trial plot, three weeks after each foliar treatment and after the corn canopy had fully closed. Individual BGNIR images were processed using drone display image analysis software to create a single orthomosaic image of the trial plot that was further analyzed with Fiji imaging software. Within the orthomosaic image, plot regions to identify individual foliar treatments in a field and the replicates per each treatment were clearly established using GPS coordinates in each field trial. The treatment replicates identified for imaging were consistent in size. For each foliar treatment, three replicates were collected with two rows imaged per each replicated plot. Within each replicate, the average intensity of light was measured for each of the image channels [blue, green, and near infrared, (visualized as red)] on a scale of 0-255, with Intensity 0=0% reflection (black pixel) and Intensity 255=100% reflection (white pixel). These average B, G and NIR light intensities were used to calculate an ENDVI value using the ENDVI algorithm for plant health (greenness) for each replicated plot. The ENDVI values were then averaged for the three plot replicates as reported in Tables 49 and 50. ENDVI values for the treatment applications were compared to the control treatments in each plot. Control treatments consisted of corn plants grown from seed that was treated with a base seed treatment only and received no foliar treatments. Foliar treatment compositions were as described using the application use rates as specified in Table 48.
Foliar compositions contained 0.1% (v/v) PROXEL BC preservative, an aqueous dispersion of a blend of 330.7 mM 1,2-benzisothiazolin (BIT), 53.5 mM 5-chloro-2-methyl-4-isolthiazolin-3-one (CMIT), and 26.1 mM 2-methyl-4-isothiazolin-3-one (MIT). Foliar compositions were applied at the indicated rates (Fl. oz/Ac or mL/Ha) in a carrier volume of 20 gallons/acre water with 0.1% (v/v) Alligare Surface™ non-ionic surfactant
As shown in Table 49, foliar applications with compositions containing Bt.4Q7Flg22 and Syn01Flg 22 applied to corn at the V5-V7 stage of development resulted in increased ENDVI measurement ratio values as compared or normalized to plants that received no foliar treatment (seed treatment control). The Bt.4Q7Flg22 compositions provided as a foliar treatment in buffered formulations (compositions 2, 3, 4 and 5; sodium phosphate pH 5.6-5.7) resulted in plants with higher ENDVI ratio values compared to the plants that received the Bt.4Q7Flg22 provided as a non-buffered composition (composition 1) applied at 4 Fl. oz/Ac or 292.3 mL/Ha. However, ENDVI ration values of Bt.4Q7Flg22 treated plants (compositions 1-5) were all increased relative to the non-treated control plants. Corn plants that received the foliar treatment application of composition 4 consisting of the Bt4Q7Flg22 polypeptide combined with cellobiose in a phosphate buffered formulation provided at 8 Fl. oz/Ac or 584.6 mL/Ha use rate resulted in a +9% increase in the average ENDVI ratio value over the control (seed treatment only) plants. Plants that received foliar applications of composition 1 and 5 which differed in composition only in the respective application use rates (4 and 48 Fl. oz/Ac or 292.3 mL/Ha and 3,507.6 mL/Ha) resulted in plants with similar ENDVI ratio values (+3% and +4%) as compared to the control plants. Importantly, the higher rate of 48 Fl. oz/Ac or 3,507.6 mL/Ha resulted in no detectable phytotoxicity, which would have been observed as a reduced ENDVI value compared to the control (seed treatment only). A synthetic derived variant version of Bt.4Q7Flg22 (Syn01Flg22) compositions 6, 7, and 8 were also provided as a foliar spray to V5-V7 corn plants. The Syn01Flg22 polypeptide provided in a phosphate buffered formulation (composition 6 and composition 7) were compared according to the application use rates. The Syn01Flg22 polypeptide (composition 6) that was provided to corn plants using a higher application use rate (4 Fl. oz/Ac or 292.3 mL/Ha) resulted in a decreased ENDVI ratio value or had a lesser percentage increase in ENDVI as compared to the Syn01Flg22 polypeptide (composition 7) applied to plants using a 0.4 Fl. oz/Ac or 29.23 mL/Ha application use rate, a change of 8% between the composition 6 and 7 treatments. The Syn01Flg22 (composition 8) had the addition of cellobiose and similar to composition 7 was provided at an application use rate of 0.4 Fl. oz/Ac or 29.23 mL/Ha. Foliar application of Syn01Flg22 (composition 7) was compared to Syn01Flg22 combined with cellobiose (320 mM) (composition 8). The Syn01Flg22 composition 7 and composition 8 had similar increases in ENDVI measurement ratios resulting in a +10% increase as compared to control plants or a +8% increase compared to plants that received the Syn01Flg22 (composition 6) provided at the higher 4 Fl. oz/Ac or 292.3 mL per hectare (Ha) use rate.
Corn seed (DEKALB hybrid DKC 52-61) was also treated with Roundup POWERMAX (active ingredient glyphosate, 48.7% in the form of potassium salt) in combination with the Bt.4Q7Flg22 composition 3. Roundup POWERMAX was applied using the recommended use rate on the specimen label of 24 Fl oz/Ac. The Bt.4Q7Flg22 (composition 3) was applied at a rate of 4.0 Fl. oz/Ac or 292.3 mL/Ha. Results are shown in Table 50.
As shown in Table 50, Roundup POWERMAX applied to corn at the V5-V7 stage of development as a foliar herbicide combined with the Bt.4Q7Flg22 (composition 3) resulted in an increased ENDVI measurement ratio, an increase of +8% compared to the treatment with the Roundup POWERMAX applied without the Bt.4Q7Flg22 polypeptide.
Example 34: Application of Bioactive Priming Polypeptides to V4-V7 Corn—Increased YieldLarge acre corn trials were planted from corn seed (DEKALB hybrids: DKC 52-61, DKC 58-89, and DKC 65-81) coated with a seed treatment comprising EVERGOL fungicide (7.18% propiconazole, 3.59% penflufen, and 5.74% metalaxyl) with PONCHO/VOTiVO 500 (a mixture of clothianidin insecticide and a microbial agent, Bacillus firmus 1-1582). Corn field trials were planted in 8 locations throughout the US Midwest (IN, IL, & IA). Field seed beds at each location were prepared using conventional or conservation tillage methods for corn plantings. Fertilizer was applied as recommended by conventional farming practices which remained consistent between the US Midwest locations. Herbicides were applied for weed control and supplemented with cultivation when necessary. Four-row plots, 5.3 meters were planted at all locations. Corn seed was planted 3.8 to 5.1 cm deep to ensure normal root development. Corn was planted at approximately on average of 42,000 plants per acre or 103,782 plants per hectare with an average row width of 0.8 meters with seed spacing of 1.6 to 1.8 seeds per every 30 cm.
Corn plants at approximately the V5 stage of development received foliar applications using a foliar composition comprising a Bt.4Q7Flg22 (SEQ ID NO: 226) polypeptide and a synthetic version of Bt.4Q7Flg22 which is described as Syn01Fflg22 (SEQ ID NO: 571) polypeptide. The foliar compositions comprising the Bt.4Q7Flg22 polypeptide and a synthetic version of Bt.4Q7Flg22 polypeptide were applied to 3 corn hybrids (DEKALB hybrids: hybrid 1: DKC 52-61; hybrid 2: DKC 58-89; hybrid 3: DKC 65-81) planted in 8 locations throughout the US Midwest (IN, IL, & IA). Corn plants received foliar treatments using the concentrations and application use rates as described in Table 51. Corn yield (Bu/Ac) was collected and reported as the average yield (Bu/Ac) across the locations (8 locations for hybrid 1, 7 locations for hybrid 2 and 6 locations for hybrid 3) and as the average change in Bu/Ac compared to the base seed treatment (ST) control treated with surfactant alone in Table 51.
Corn plants at approximately the V5 stage of development received foliar applications using a foliar composition comprising a Bt.4Q7Flg22 and a synthetic version Syn01Flg22 of Bt.4Q7Flg22 polypeptides. The Bt.4Q7Flg22 and a synthetic version of Bt.4Q7Flg22 polypeptides were also combined with cellobiose (320 mM), a reducing sugar, consists of two β-glucose molecules linked by a β-(1→4) bond and provided as an elicitor treatment to enhance the effect of the Flg22 polypeptide. Both the Bt.4Q7Flg22 and the Syn01Flg22 provided in combination with cellobiose to corn plants resulted in an enhanced yield boast over the Bt.4Q7Flg22 and the Syn01Flg22 foliar applied polypeptides. A positive increase in yield of +2.55 Bu/Ac or 160 kg/Ha resulted in the corn plants that received the Bt.4Q7Flg22 foliar treatment with cellobiose as compared to the +1.14 BuAc or 71.6 kg/Ha increase in yield for the Bt. 4Q7Flg22 foliar treatment provided alone. There was also a positive increase in yield of +1.59 Bu/Ac or 99.8 kg/Ha resulted in the corn plants that received the Syn01Flg22 (0.2 Fl. oz/Ac or 14.6 mL/Ha) foliar treatment provided in combination with cellobiose as compared to the +1.48 BuAc or 92.9 kg/Ha increase in yield for the Syn01Flg22 foliar treatment provided at the same application use rate. Whereas, the Bt.4Q7Flg22 and the Syn01Flg22 provided as foliar treatments to corn plants at the V5 stage of development using a 4.0 Fl. oz use rate or 292.3 mL/Ha provided a slightly lower increase in yield +1.14 Bu/Ac (71.6 kg/Ha) and +0.90 Bu/Ac (56.5 kg/Ha) as compared to the combinations of the two Flg22 polypeptides with cellobiose.
Example 35: Combination of a Synthetic-Derived Flg22 (Syn01Flg22) and a FungicideIn a further study, large acre yield trials were conducted using a foliar application comprising a compositions of the Bt.4Q7Flg22 polypeptide and a synthetic derived polypeptide from Bt.4Q7Flg22 (Syn01Flg22) provided with a broad-spectrum fungicide, STRATEGO YLD (10.8% prothioconazole and 32.3% thiofloxystrobin). STRATEGO YLD is a commercially available fungicide suitable for use as an early season foliar application for corn was applied as a foliar spray following the recommendations on the specimen label at a use rate of 4.0 fluid ounces per acre (Fl. oz/Ac) (292.3 mL/hectare). Corn plants at approximately the V5 stage of development received foliar applications using a foliar composition comprising the Bt.4Q7Flg22 polypeptide and Syn0Flg22, the synthetic version of Syn01Flg22 polypeptide combined with the STRATEGO YLD fungicide. Foliar treatments were applied to 2 corn hybrids (DEKALB hybrids: hybrid 1: DKC 52-61; hybrid 2: DKC 58-89) planted in 2 locations Iowa. Corn yield (Bu/Ac) was collected and reported as the average yield (Bu/Ac) across the 2 locations for both hybrids and as the average change in Bu/Ac compared to the corn plants grown from seed that received the base seed treatment (ST) and only the foliar application with the STRATEGOYLD fungicide (Table 52).
Foliar application to V5 corn plants with the Bt.4Q7Flg22 and the Syn01Flg22 polypeptides that were provided in combination with a fungicide, STRATEGO YLD at the concentrations and application use rates as specified in Table 5 above resulted in a more than a +5 Bu/Ac. The Syn01Flg22 polypeptide foliar treatment resulted in slightly higher corn yields of +5.84 Bu/Ac (366.6 kg/Ha) than the corn plants that received the Bt.4Q7Flg22 polypeptide treatment which resulted in average yields of +5.50 Bu/Ac (345.2 kg/Ha) as compared to the plants that received the foliar treatment with only the STRATEGO YLD fungicide.
Example 36: Seed Treatment with Flg22 Polypeptides to Increase Yield in CornIn other studies, large acre yield trials were conducted using a base seed treatment consisting of ®EVERGOL fungicide (7.18% propiconazole, 3.59% penflufen and combined with 5.74% metalaxyl) and PONCHO/VOTiVO 500 (a mixture of 40.3% clothianidin insecticide and 51.6% Bacillus firmus 1-1582, a microbial agent) provided in combination with various Flg22 polypeptides. Seed treatments were applied to 3 corn hybrids (BECK's 4919V2, 5140HR and 5828YX) planted in 8 locations throughout the US Midwest (IN, IL, & IA). Seed treatment compositions of the Flg22 polypeptides were applied as described in Table 53 as Fl. oz per unit of corn or soy seeds in a total slurry volume containing the base seed treatment Bt.4Q7Flg22 from Bacillus thuringiensis (Composition 10) and Pa.Flg22 from Paenibacillus alvei (Composition 11). Final concentration of polypeptide in the slurry for Compositions 10 and 11 was 1 uM.
Corn yield (Bu/Ac) was collected and reported as the yield (Bu/Ac) across the 8 locations averaged for all 3 hybrids. The average change in Bu/Ac was as compared to the corn plants grown from seed that received the only the base seed treatment (ST) and is reported in Table 54.
Treatment of corn seed with Bt.4Q7Flg22 (SEQ ID NO: 226) and Pa.Flg22 (SEQ ID NO: 293) polypeptides increased yield as represented as an average over the 3 corn hybrids and the 8 US Midwest locations. The Bt.4Q7Flg22 polypeptide provided as a seed treatment resulted in an even greater yield advantage or a +4.73 Bu/Ac (296.9 kg/Ha) compared to the control plants. The Pa.Flg22 applied as a seed treatment also resulted in a yield gain with a +3.57 Bu/Ac (224 kg/Ha) over corn plants grown from seed that received only the base seed treatment. Thus, Flg22 polypeptides obtained from different species of bacteria (Bacillus and Paenibacillus) both resulted in substantial yield increases when applied as a seed treatment on corn seed.
Example 37: Application of Flg22 Polypeptides with Cellobiose to Increase Yield in CornLarge acre corn trials were planted from corn seed (DEKALB hybrids: DKC 52-61, DKC 58-89, and DKC 65-81) containing a seed treatment comprising EVERGOL fungicide (7.18% propiconazole, 3.59% penflufen and combined with 5.74% metalaxyl) combined with PONCHO/VOTiVO 500 (a mixture of clothianidin insecticide and a microbial agent, Bacillus firmus 1582). Corn plants at approximately the V5 stage of development received foliar applications using an agricultural composition comprising a Bt.4Q7Flg22 and the synthetic Syn01Flg22 polypeptides were provided with and without cellobiose (320 mM). The foliar treatments were applied to 2 corn hybrids (DEKALB hybrids: hybrid 1: DKC 58-89; hybrid 2: DKC 65-81) planted in 2 locations in the US Midwest (IL) that experienced drought-like conditions after foliar application, during the pollination stage of corn development. Corn plants received the Bt.4Q7Flg22 and Syn01Flg22 foliar treatments using the concentrations and application use rates as described in Table 48 with a non-ionic surfactant (Alligare Surface™ applied at a final concentration of 0.1% v/v of spray tank volume). Corn yield (Bu/Ac) was collected and reported as the average yield (Bu/Ac) across the 2 locations for the 2 hybrids and as the average change in Bu/Ac compared to yield from corn plants that received only base seed treatment (ST) and a non-ionic surfactant (Alligare Surface™ applied at a final concentration of 0.1% v/v of spray tank volume) (Table 55).
Foliar treatment applications of Bt.4Q7Flg22 (SEQ ID NO: 226) and a synthetic version of Syn01Flg22 (SEQ ID NO: 571) resulted in substantial yield gains in corn plants when combined in a foliar treatment application with cellobiose, a disaccharide that is used as a secondary stabilization agent for the Flg polypeptide and vehicle for delivery to the plant membrane surface. The Bt.4Q7Flg22 polypeptide (16.7 μM) provided with cellobiose (320 mM) as a combination foliar spray applied using 4.0 Fl. oz/Ac application use rate (Flg22) resulted in a more than doubled yield gain, a +8.22 Bu/Ac increase or approximately 516 kg/ha over the control plants in comparison to 4.0 Fl. oz/Ac Bt.4Q7Flg22 polypeptide alone. The Bt.4Q7Flg22 polypeptide applied without cellobiose resulted in a +3.70 Bu/Ac or 232 kg/Ha increase over the control plants grown from the surfactant control. Similar increased yield resulted in corn plants treated with the Syn01Flg22 and the combination of Syn01Flg22 (16.7 μM) provided in combination with cellobiose (320 nM) using a 0.2 Fl. oz/Ac application use rate, a respective increase of +9.60 (602.6 kg/Ha) and +15.48 (971.6 kg/Ha) compared to the yield obtained from the surfactant control plants. Additionally, the Bt.4Q7Flg22 (16.7 μM) polypeptide was provided as a foliar spray application using three different application use rates of 0.2, 2.0 and 24.0 Fl. oz/Ac (14.6 mL/Ha, 146.2 mL/Ha and 1753.8 mL/Ha) to corn plants at the V5-V7 stage of development. The Bt.4Q7Flg22 polypeptide delivered using the highest use rate resulted in a substantially higher yield advantage, an almost +27 Bu/Ac (1694.6 kg/Ha) yield increase over the yield obtained from the control plants. Overall, Bt.4Q7Flg22 and a synthetic version of Syn01Flg22 provided protection from drought-like growth conditions during a critical stage of plant development (i.e. pollination), resulting in increased yield for all combinations of Bt.4Q7Flg22, Syn01Flg22 and cellobiose used as foliar applications.
In another study, seed treatments using Flg22 polypeptides and combinations of Flg22 polypeptides with cellobiose resulted in overall yield increases in field trials reported as an average for four replicated trials (Table 56). Seed treatments were applied to corn hybrid (BECK's 5828YX) planted in 1 locations in the US Midwest (Columbia). Seed treatment compositions of Flg22 were applied as described in Table 56 as 0.14 Fl. oz per unit of corn seeds in a total slurry volume containing the base seed treatment. Final concentration of the Flg22 polypeptides in the slurry for were standardized to 1 uM per seed. The same final concentration of cellobiose that was applied in combination treatments with the Flg22 polypeptides was at 1.0 mM per seed. The average yield in Bu/Ac and the average increase in Bu/Ac as compared to the untreated control (column 1) and to the Bt.4Q7Flg22 (SEQ ID NO:226) (column 2) is reported for corn grown from seed that received the Flg22 polypeptide combination treatments as described below in Table 56.
Large acre soybean trials were planted from uncoated soybean seed. Soybean seed was planted 1.5 to 2 inches deep (approximately 5 cm) to ensure normal root development. Soybean was planted in 12.5′ (3.8 meter) plots with an average of 150,500 plants per acre, row widths of 30 inch rows (0.8 meter) and seed spacing of 7 to 8 seeds per foot (30 cm).
Agricultural compositions comprising agriculturally effective amounts of compositions of Bt.4Q7Flg22 (SEQ ID NO: 226), Syn01Flg22 (SEQ ID NO: 571) and a Flg22 from Aneurinbacillus thermoaerophilus, At.Flg22-B4 (SEQ ID NO: 300) were applied to soybean. The Flg22 polypeptide treatments were applied as a foliar spray at application use rates (Fl. oz/Ac or mL/Ha) as specified in Table 57 to soybean grown at five US Midwest locations (participating sites: IA and IL). The soybean plants received foliar treatments containing Bt.4Q7Flg22 (SEQ ID NO: 226); Syn01Flg22 (SEQ ID NO: 571) and At.Flg22-B4 (SEQ ID NO: 300) at approximately the V4-V6 stage of development with a non-ionic surfactant to facilitate spreading and uptake of treatments (Alligare Surface™ applied at a final concentration of 0.1% v/v of spray tank volume). Soybean yield was collected for the 3 soybean varieties (Asgrow: AG2733, AG3536 and AG4034) for plants receiving the Flg22 compositions. Soybean yield was also reported as the change in yield Bu/Ac compared to the control soybean plants that received a non-ionic surfactant (Alligare Surface™ applied at a final concentration of 0.1% (v/v) only treatment (Table 57).
Foliar application of the Bt.4Q7Flg22 and Syn01Flg22 polypeptides were also combined with cellobiose as an additive and examined for the effect of Flg22 polypeptides combined with the cellobiose additive on yield increase. Cellobiose is a glucose disaccharide and a building block for cellulose polymer. Chemically, it is glucose-beta-1-4-glucose, a reducing sugar that consists of two β-glucose molecules linked by a β (1-4) bond. Cellobiose is obtained by the breakdown of cellulose or lichenin and yields glucose upon hydrolysis. The cellobiose additive combined with Bt.4Q7Flg22 resulted in an increase in reactive oxygen species (ROS) activity in soybean. Soybean yield was collected for the 3 soybean varieties (Asgrow: AG2733, AG3536 and AG4034) for plants receiving the Flg22 compositions with and without the cellobiose additive and reported as the average yield (Bu/Ac) for all 3 varieties across locations. Soybean yield was also reported as the change in yield Bu/Ac compared to the control soybean plants that received a non-ionic surfactant (Alligare Surface™ applied at a final concentration of 0.1% v/v only treatment) (Table 57).
Foliar treatment of the various Flg22 polypeptides, Bt.4Q7Flg22; Syn01Flg22 and At.Flg22-B4 (Compositions 1-9) all resulted in yield benefits when applied on soybean at the V4-V6 stage of development compared to the control soybean plants that were treated with a foliar application of surfactant alone. Foliar treatment with Bt.4Q7Flg22 (Composition 3) applied at 4.0 Fl. oz/Ac resulted in a +2.51 Bu/Ac (168.8 kg/Ha) increase over control plants (surfactant only). The Syn01Flg22 (Composition 6) polypeptide applied as a foliar treatment using 4.0 Fl. oz/Ac to soybean plants resulted in a yield gain of +1.76 Bu/Ac (118.4 kg/Ha) compared to the surfactant only control plants. Syn01Flg22 (Composition 7) and Syn01Flg22 with the cellobiose (320 nM) (Composition 8) applied to soybean plants using a lower application use rate of 0.2 Fl. oz/Ac resulted in an increase of +1 Bu/Ac with the addition of the cellobiose additive or an overall +2.56 Bu/Ac (172.2 kg/Ha) increase in yield over the control plants. The At.Flg22-B4 (Composition 9) polypeptide applied to soybean (V4-V6) also resulted in a yield benefit of +2.3 Bu/Ac (154.7 kg/Ha) compared to the control plants or over 3.5 Bu/Ac (235.4 kg/Ha) as compared to plants that received treatment with the non-ionic surfactant only.
In still another study, seed treatments using Flg22 polypeptides and combinations of Flg22 polypeptides with cellobiose were used as seed treatments on soybean and resulted in overall yield increases in field trials reported as an average for four replicated trials (Table 58). Seed treatments were applied to 1 soybean hybrid (variety) planted in 1 locations in the US Midwest (Columbia, Mo.). Seed treatment compositions of Flg22 were applied as described in Table 58 as 0.14 Fl. oz per unit of soybean seeds in a total slurry and provided to soybean seed that had a base seed treatment consisting of Poncho VOTiVO 600 FS and Evergol Energy. The application use rates per each seed treatment were held constant at 0.14 Fl. oz/Ac or 4.14 mL/unit. Final concentration of the Flg22 polypeptides in the slurry for were standardized to 1 uM per seed. The same final concentration of cellobiose that was applied in combination treatments with the Flg22 polypeptides was at 1.0 mM per seed. Four replicate plots per each seed treatment were randomized over the location. The average yield in Bu/Ac and the average change in Bu/Ac as compared to the control plants that received only the base seed treatment are reported in Table 58. The most substantial yield increases were seen with Bt.4Q7Flg22 (SEQ ID NO: 226) and Syn01Flg22 (SEQ ID NO: 571) when applied as a seed treatment on soybean delivered at a final concentration of 1.0 μM of the Flg22 polypeptides and resulting in respective average yield increases of +5.11 (343.7 kg/Ha) and +9.92 (667.1 kg/Ha) over yield from soybean that received the base seed treatment.
Large acre corn trials were planted from corn seed (DEKALB hybrids: DKC 52-61, DKC 58-89, and DKC 65-81) containing a seed treatment comprising EVERGOL fungicide (7.18% propiconazole, 3.59% penflufen and combined with 5.74% metalaxyl) combined with PONCHO/VOTiVO 500 (a mixture of clothianidin insecticide and a microbial agent, Bacillus firmus 1582). Corn plants at approximately the V5 stage of development received a foliar application using an agricultural composition comprising an Gm.RHPP polypeptide (SEQ ID NO: 600). The formulated Gm.RHPP polypeptide (Table 59) was applied to the corn hybrids using an application use rate of 8.0 Fl. oz/Ac (584.6 mL/Ha) with 0.1% v/v (of spray tank) non-ionic surfactant (Alligare Surface™). In total, the trial was conducted at 6 locations in the US Midwest (IL, IN, IA), with 1-2 hybrids per location and 3 replicated plots per hybrid. Corn yield (Bu/Ac) was collected and reported as the average yield (Bu/Ac). The average change in Bu/Ac was compared to the yield of plants grown from the surfactant control and reported as the combined average yield (Bu/Ac) for the 6 locations (11 replicated plots in total) and as overall change in Bu/Ac as compared to control plants. Results are shown in Table 59.
Foliar treatment of plants with the Gm.RHPP polypeptide resulted in increased yields in corn compared to plants that received surfactant alone. The average yield per the 6 locations combined for corn plants that received the Gm.RHPP polypeptide foliar treatment was slightly more than 209 Bu/Ac as compared to 206 Bu/Ac or for the control plants. The yield for the Gm.RHPP treated plants was increased by 3.52 Bu/Ac or 220.9 kg/Ha as compared to the yield from the corn control plants (Table 59).
Example 40: RHPP Polypeptide Increases Pod Number In SoybeanSoybean (variety MorSoy) plants were grown from seed with 2 seeds planted per pot in a controlled environmental growth room under conditions of approximately 300 μmol−2 s−1 (light photons) for a 13/11 light/day cycle and a 21° C. day/15° C. night temperature range until the V4 stage of development. Plants were then placed under a long day conditions consisting of 16/8 light/day cycle and temperature 21-26° C. to promote early flowering and speed up progression to the reproductive (R) growth stage. When the soybean plants had reached the R1 stage of development a foliar application containing the Gm.RHPP (SEQ ID NO: 600) polypeptide at a final concentration of 300 nM and a non-ionic surfactant of 0.10% (NIS90:10; Precision Laboratories, LLC) was applied to soybean. Soybean plants were provided with the Gm.RHPP formulation and a non-ionic surfactant only control. Both the Gm.RHPP and the non-ionic surfactant control treatment were applied to 18 plants per treatment. Six equidistant sprays were provided approximately 15 cm above per each plant for complete coverage of foliage. After treatment application, the R1 soybean plants were returned to the control environmental growth room. After seventeen days, the plants received another foliar treatment application with the formulation containing the Gm.RHPP polypeptide and the non-ionic surfactant as well as the non-ionic surfactant only treatment. Soybean pods of more than 1 mm in length were counted on the plants after 31 days from the first foliar spray treatment applications. The average number of pods per plant and the standard deviation from the overall average are reported (Table 60). A p value (p<0.05 for significance) was calculated from a paired T-test comparison between pod number from plants that received the Gm.RHPP and the non-ionic surfactant control treatment applications.
Foliar application of the Gm.RHPP polypeptide at early reproductive stage (R1) of soybean plants resulted in an approximately doubled pod count as compared to plants that received the non-ionic surfactant control treatment.
Example 41: Flg22 and RHPP Polypeptides Increase Yield in Tomato and PepperFoliar application treatments of Bt.4Q7Flg22 (SEQ ID NO: 226) and Gm.RHPP (SEQ ID NO: 600) were applied as an exogenous spray at the pre-bloom stage and used to increase yield in tomatoes and jalapeno peppers.
Small scale plots were designed to simulate commercial growing conditions for tomatoes. Tomato plants, variety Roma were started from transplants that were grown in a greenhouse for 45 days prior to planting into 2 raised field row beds with 2 feet (0.6 meters) between each transplant with an average of 30 plants per row bed. Tomatoes were transplanted three inches beneath the soil surface once the soil temperature reached 15.6° C. Tomatoes were grown on raised beds covered with black plastic mulch. Plants were grown using drip irrigation and fertilizer (80 lbs. or 36.3 kg) nitrogen; 100 lbs. (45.4 kg) phosphate, and 100 lbs. (45.4 kg) potash or potassium) applied following grower guidelines throughout the growing season to provide for optimum plant growth and yields. Small raised bed plots were designed to simulate the planting densities used by commercial growers that generally plant 2,600 to 5,800 plants per acre in single rows with 45.7 to 76.2 cm between plants in the row on 1.5- to 2-meter centers. [Orzolek et al., “Agricultural Alternatives: Tomato Production.” University Park: Penn State Extension, 2016].
Foliar treatments using Bt.4Q7Flg22 and Gm.RHPP were applied on the tomato plants directly at early bloom (first flower) stage. The Bt.4Q7Flg22 polypeptide foliar composition was applied using an application use rate of 4.0 Fl. oz/Ac (292.3 mL/hectare) and the Gm.RHPP polypeptide foliar composition was applied using an application use rate of 3.2 Fl. oz/Ac (234 mL/hectare) on tomato plants in 10 gallons of water per acre with 0.1% v/v non-ionic surfactant (Alligare™ Surface). The Bt.4Q7Flg22 and Gm.RHPP treated plants were compared to the control plants that received no foliar treatment application. Plants were treated in replicates of 6 plants, with three replicates per treatment. Effect of the foliar treatments on the yield obtained from tomatoes was determined and reported as normalized to no spray control treatment. The average fruit weight per tomato plant is reported as the combined average for 2 separate harvests and the average percentage change in fruit weight as compared to the no-spray control in Table 61.
Foliar treatment application with the Bt.4Q7Flg22 polypeptide provided at a concentration of 16.7 μM and an application use rate of 4.0 Fl. oz/Ac (292.3 mL/hectare) resulted in an overall increase in the average fruit weight per plant as reported in total grams and an +8.61% change in fruit weight as compared to the no spray control. The Gm.RHPP polypeptide provided at a concentration of 100 μM and a 3.2 Fl. oz/Ac (234 mL/hectare) application use rate also resulted in yield overall increase in average fruit weight (grams) per plants and an almost +2% change in fruit weight as compared to the no spray control.
In another study, foliar treatments with the Bt.4Q7Flg22 (SEQ ID NO: 226) and Gm.RHPP (SEQ ID NO: 600) polypeptides were applied on jalapeno peppers (Capsicum) plants at early bloom (first flower) stage. Small-scale plots were designed to simulate commercial growing conditions for jalapeno peppers. Peppers were grown for 12-weeks in a controlled growth room and then transplanted outside in 2 raised beds covered with black plastic mulch that had good water-holding characteristics and in soil having a pH of 5.8-6.6. Jalapeno pepper plants were spaced 14-16 inches (38 cm) apart with 16-24 inches (50 cm) between plants containing approximately 25 plants per row bed. Plants were grown using drip irrigation and fertilizer applied following grower guidelines throughout the growing season to provide optimum conditions for plant growth. The raised bed plots were designed to simulate the planting densities used by commercial growers that generally plant approximately plants per acre (5,000-6,500 plants per acre or 12,355-16,062 plants per hectare) in double rows 35.6-45.7 cm apart with the beds spaced 5.0-6.5 feet (1.52-1.98 meters) apart from their centers (Orzolek et al., “Agricultural Alternatives: Pepper Production.” University Park: Penn State Extension, 2010).
Foliar treatments using the Bt.4Q7Flg22 and Gm.RHPP polypeptides were applied on jalapeno pepper using application use rates of 2.0 Fl. oz/Ac (146.2 mL/hectare) and 4.0 Fl. oz/Ac (292.3 mL/hectare) for Bt.Flg22 and 3.2 Fl. oz/Ac (234 mL/hectare) for the Gm.RHPP polypeptide in a spray volume of 10 gallons of water per acre with 0.1% v/v non-ionic surfactant (Alligare™ Surface). Plants were treated in replicates of 6 plants, with three replicates per treatment. Replicates with average yield per plant 50% above or 50% below the median yield for the trial were excluded as outliers. The Bt.4Q7Flg22 and Gm.RHPP polypeptide foliar treatments applied on jalapeno pepper plants were compared to plants sprayed with 10 gallons of water per acre with 0.1% v/v non-ionic surfactant (Alligare™ Surface) alone.
Effects of the Bt.4Q7Flg22 and Gm.RHPP polypeptides used as foliar spray applications on pepper yield were determined for two separate harvests using a once over harvest approach. The number of peppers and the above ground biomass per plant were normalized to the yield and to the biomass of the pepper control plants that were treated with surfactant alone (Table 62).
The Bt.4Q7Flg22 polypeptide applied as a foliar spray application to Jalapeno pepper at the pre-bloom stage resulted in substantial increases in average fruit weight per plant, a +49% increase for 2 Fl. oz/Ac (146.2 mL/hectare) and +40% increase for 4 Fl. oz/Ac (292.3 mL/Ha) as compared to the surfactant only control plants. The Gm.RHPP polypeptide treatment also applied as a foliar spray at the pre-bloom stage also resulted in an increased average fruit weight in Jalapeno peppers per plant with a +27% increase in the weight of peppers as measured on a per plant basis as compared to the peppers harvested from the surfactant only control plants.
Example 42: Application to Squash-Increased YieldFoliar treatments containing the Bt.4Q7Flg22 or the Gm.RHPP polypeptide was applied exogenously as a foliar treatment to Crookneck squash at the first bloom stage. Foliar treatments with the Bt.4Q7Flg22 and the Gm.RHPP polypeptide were applied to squash plants using an application use rate of 2.0 Fl. oz/Ac (146.2 mL/hectare) or 3.2 Fl. oz/Ac (234 mL/hectare), respectively, in a spray volume of 10 gallons of water per acre with 0.1% v/v non-ionic surfactant (Alligare™ 90). Yield comparisons were made between the plants treated with the polypeptides compared to surfactant only control plants, with three replicates per treatment. Yield for the foliar treated plants that received the Bt.4Q7Flg22 or Gm.RHPP polypeptide treatment are reported in Table 63 as the average weight (grams) of squash per plant over two harvests per replicate and represented as a percentage change as compared to control plants. Replicates with average yield per plant 50% above or 50% below the median yield for the trial were excluded as outliers.
Squash plants were cultivated in sandy loam soil as follows. 2.5 cm holes were cut in 0.76 meters wide plastic covered mounds, two rows per mound, holes spaced 0.46 meters apart within each row. Rows were staggered within the mound. Mounds were spaced 1.2 meters apart. Three squash seeds were planted per hole and thinned to a single plant per hole 14 days after planting. Drip irrigation tubing was laid in the center of each mound, and plants were watered as necessary.
Foliar treatment with either Bt.4Q7Flg22 or Gm.RHPP polypeptide on squash plants at the pre-bloom stage both resulted in an increased weight of harvested squash fruit by an average by 31.7 grams per plant or +4.4% change in fruit weight as compared to the surfactant only control plants (Table 63).
Example 43. Flg22 Polypeptide Reduces Severity of White Leaf Spot on KaleIn a replicated Fall season kale trial in the Midwest (Columbia, Mo.), very wet and warm growing conditions led to the development of white leaf spot on the kale leaves, which is typically caused by Cercospora brassicicola. The infected kale plants had received no previous foliar treatments for fungal disease prevention. To assess the severity of disease, a scoring rubric (1-5 scale) was established where 1=a healthy plant with three or fewer white fungal spots, 2=a plant with more four or more spots and a portion of the foliage is affected by disease, 3=majority of the foliage shows symptoms and up to one leaf has fallen off due to disease, 4=majority of the foliage shows symptoms and 2-3 leaves have fallen off due to disease, and 5=majority of the foliage shows symptoms and four or more leaves have fallen off due to disease. A single person scored all the plants within the trial area, and then evenly distributed the plants by disease score between the treatments in Table 64, with 6 replicated blocks of 6 plants per treatment (total=36 plants per treatment). To test Bt.4Q7Flg22 (SEQ ID NO: 226) for improvement of disease symptoms on kale, treatments were applied as a foliar spray at the indicated rates in Table 64 in a carrier volume of 10 gallons of water per acre with 0.1% v/v non-ionic surfactant (Alligare™ Surface). Three weeks after foliar treatments, the plants were scored used the same disease severity rubric. The change in disease score was calculated for each plant, and the average change in disease score was determined per treatment. Plants were harvested four days after assessing disease severity, and yield was measured as plant weight (grams). Outlying values with weights that were either 50% below or 50% above the median weight for the trial were excluded from the dataset.
Foliar treatment of infected kale plants with formulated Bt.4Q7Flg22 (SEQ ID NO: 226) led to an improvement in yield and disease symptoms over the control (Table 64). While untreated controls had an average plant weight of 14.6 g, plants receiving foliar Bt.4Q7Flg22 had an average plant weight of 15.1 g and an average improvement in disease scoring of 0.5 points over control. The application of copper fungicide improved plant disease scores to the same extent as Bt.4Q7Flg22, yet decreased yield by 21% (11.5 g) compared to the control. The combination treatment of copper fungicide with Bt.4Q7Flg22 increased yield to 12.4 g per plant, but overall Bt.4Q7Flg22 alone gave the greatest yield and plant health benefit in the trial. In conclusion, Flg22 polypeptides can used to slow the progression of fungal infections in vegetables and increase yield under stressful growing conditions.
Example 44: ROS Screening Assays to Determine Compatibility of Flg22 Polypeptide with Seed TreatmentsSeed treatments were examined for compatibility with the production of apoplastic reactive oxygen species (ROS) in corn petiole tissues. Various commercially available seed treatments were examined for compatibility with the Flg22 polypeptide (Bt.4Q7Flg22; SEQ ID NO: 226) shown to increase yield when applied alone as a seed treatment on corn. ROS activity assays were conducted using corn petiole samples from corn hybrid 5828 YX as described in Example 15 with the exception that Relative light units (RLUs) were recorded with a SpectraMax L luminometer (0.5 s integration; 2.0 min intervals) over a time course of 40 minutes. Varying concentrations of Bt.4Q7Flg22 (0 and 1000 μM) were combined with three commercial seed treatments consisting of PPST 2030 (a combination of bacteria, Bacillus subtilis 5×108 cfu/mL and Bacillus pumilus 5×108 cfu/mL), ILEVO (48.4% fluopyram) and PONCHO/VOTiVO (a mixture of 40.3% clothianidin and a microbial agent, Bacillus firmus 1-1582) and tested for the presence of a ROS response in corn petioles. All three seed treatments as described were applied using the application use rates per seed as recommended on the individual specimen label for each seed treatment. A standard curve was generated using varying concentrations of the Bt.4Q7Flg22 polypeptide and resulted in a logarithmic correlation between the RLU and concentration of Flg22 with an R2 of 0.90. The RLU values are the average of 4 separate measurements (4 treatment wells on each plate) and the increase in overall ROS (RLU) (times increase over the background) are shown in parentheses (Table 65).
ROS production as measured by RLUs were increased with the addition of 1 μM Bt.4Q7Flg22 when combined with each of the seed treatments as described in Table 65. The ROS production (RLU values) with the 1:10 dilution of the seed treatments with the addition of 1 μM Bt.4Q7Flg22 was also increased as compared to the back ground RLU level for the seed treatment only or no Bt.4Q7Flg22 polypeptide. The diluted PONCHO/VOTiVO seed treatment combined with 1 μM Bt.4Q7Flg22 was increased more than 15× compared to the background or 2.2× compared to the non-diluted PONCHO/VOTiVO treatment applied per seed following the recommendation on the specimen label. Therefore, the Flg22 polypeptide is detectable by ROS assay when combined with standard seed treatment base at label rates. When combining such Flg22 polypeptides with a particular seed treatment, adjustment of either the polypeptide concentration or the seed treatment concentration can be taken into consideration to ensure an optimal ROS response in the plant. These demonstrate the activity of the Flg22 polypeptides on plants in the presence of other seed treatment packages on the market today.
Example 45: Combinations of Flg22 and FlgII-28 Peptides to Increase ROS Activity in TomatoIn a separate study, the Flg22 and FlgII-28 polypeptides derived from distinct regions of flagellin protein were tested separately and in combination for compatibility of response in tomato leaves. While Flg22 and FlgII-28 are both microbe-associated molecular patterns (MAMPs) they may be recognized distinctly by the Flagellin-sensing 2 (FLS2) and Flagellin-sensing 3 (FLS3) receptors, respectively (Hind et al., 2016; Nature Plants 2:16128), and the interactions may differ across plant species. Several Flg22 polypeptides (Bt.4Q7Flg22, SEQ ID NO: 226; Bt.4Q7Flg22-Syn01, SEQ ID NO: 571 and Ec.Flg22, SEQ ID NO: 526) were compared using ROS activity assays in tomato to several FlgII-28 polypeptides (Ps.tomatoFlgII-28, SEQ ID NO: 751; A.sp.FlgII-28, SEQ ID NO: 375).
Tomato leaves were excised from 4-week-old plants using a cork borer to generate 4 mm disks. Each disc was cut in half using the edge of a razor blade, and then each disc half was floated on 150 μL of water in a 96-well plate to rest overnight. The next day, the water was removed from each well just prior to polypeptide treatment. The Flg polypeptides as described in Table 66 were added to water to bring them to a final concentration of 5 nM (Table 67) and 100 nM (Table 68) in solution with luminol and HRP before adding to each treatment well. To maintain activity, the polypeptides were stored in small aliquots to avoid multiple freezing and thawing. All dilutions to obtain working concentrations were done in ultrapure water. Polypeptide solutions were stored at −20° C. for short term usage or −80° C. for long term storage. RLU values and relative ROS activity (Tables 67, 68) is reported as the average of 4 measurements. ROS activity assays were conducted using the methods as previously reported in Example 15 with the exception that Relative light units (RLUs) were recorded with a SpectraMax L luminometer (0.5 s integration; 2.0 min intervals) over a time course of 40 minutes.
It was determined from the results in Table 67 and Table 68 that a second epitope of flagellin, termed FlgII-28 derived from either Gram-negative Pseudomonas syringae pv.tomato DC3000 or Gram-positive Aneurinibacillus sp. XH2 (SEQ ID NO: 375) are sufficient to trigger an immune response (e.g. ROS production) in tomato (SEQ ID NO: 751) at both 5 nM and 100 nM concentrations. At the 5 nM concentration, Ps.tomato FlgII-28 had the highest activity as compared to the other Flg22 and FlgII-28 polypeptides and resulted in an almost 31 times increase in RLUs as compared to Bt.4Q7Flg22 at the same concentration, whereas 5 nM A.spp.FlgII28 gave an equally low ROS response to 5 nM Bt.4Q7Flg22. The Flg22 polypeptide (Ec.Flg22; SEQ ID NO: 526) from Gram-negative Escherichia coli also resulted in increased ROS activity when applied to tomato leaves, with RLU values 12.9 X over the Bt.4Q7Flg22 treatment alone. The Bt.4Q7Flg22 (SEQ ID NO: 226) polypeptide triggered a very low ROS response in tomato leaves at the 5 nM concentration, but provided a high response at the 100 nM concentration. Ps.tomato FlgII-28, on the other hand, provided a strong ROS response in comparison to the negative control (water) at both tested concentrations. Thus, tomato leaves display increased sensitivity to Flg polypeptides derived from gram-negative bacteria Flagellin such as Ps.tomato FlgII-28 and Ec.Flg22. In addition, a synthetic variant of Bt.4Q7Flg22 termed Syn01Flg22 (SEQ ID NO: 571) had substantially increased activity (3.5×) as compared to Bt.4Q7Flg22 treatment when tested at the 5 nM concentration.
As indicated in Table 68, combinations of Gram-positive (Bt.4Q7Flg22; SEQ ID NO: 226) and Gram-negative Ps.tomato FlgII-28 (Pseudomonas syringae pv. tomato DC3000; SEQ ID NO: 751) can be used as a combined foliar application to increase ROS production over either treatment alone, and enhance plant immunity against certain pathogenic organisms.
Example 46: Synthetic Flg22Syn01 and Flg-15Syn01 Polypeptides to Increase ROS Activity in Corn and SoybeanA truncated version of Syn01Flg22 derived from Bt.4Q&Flg22 lacking seven N-terminal amino acids was generated, resulting in the 15 amino acid polypeptide with the sequence nh2-RINSAKDDAAGLAIA-cooh. This polypeptide, termed Bt.4Q7Syn01Flg15 (SEQ ID NO: 752) is a naturally occurring polypeptide among the Gram-negative proteobacteria but is absent from Gram-positive protein sequences. The core sequence required for receptor interaction, RINSAKDD, is retained in the shortened polypeptide, and thus the 15-amino acid variant was predicted to be active for triggering ROS production in plants. To test this, Syn01Flg15 was compared to Bt.4Q7Flg22 and Syn01Flg22 in ROS assays with both corn (Table 69) and soybean (Table 70). ROS activity assays were conducted using the methods as previously reported in Example 15 with the exception that Relative light units (RLUs) were recorded with a SpectraMax L luminometer (0.5 s integration; 2.0 min intervals) over a time course of 40 minutes.
In the ROS activity assay with corn (Table 69), the Flg22□Syn01 (SEQ ID NO: 571) had the greatest ROS response in corn stalk tissue at both the 100 nM and 10 nM concentrations as indicated by the relative respective activities of 1.6× (100 nM) and 0.5× (10 nM) as compared to treatment using Bt.4Q7Flg22 (SEQ ID NO: 226) that has an attenuated ROS response of 0.2× at 10 nM. The shortened version of Syn01Flg22 (SEQ ID NO: 571) or Syn01Flg15 (SEQ ID NO: 752) also exhibited a greater ROS response of 0.4× at 10 nM, which was twice the relative ROS activity of Bt.4Q7Flg22 (SEQ ID NO: 226) at the same concentration.
Likewise, in the ROS activity assay with soybean (Table 70), the synthetic derived mutant of Bt.4Q7Flg22 described as Bt.4Q7Flg22□Syn01 (SEQ ID NO: 571) also had the greatest ROS response in soy leaf tissue at both the 100 nM and 10 nM concentrations as indicated by the relative respective activities of 1.25× (100 nM) and 0.25× (10 nM) as compared to treatment using Bt.4Q7Flg22 (SEQ ID NO: 226) that has a highly attenuated ROS response of 0.04× at 10 nM. The shortened version of Syn01Flg22 or Syn01Flg15 also exhibited a greater ROS response of 0.17× at 10 nM, which was four times the relative ROS activity of Bt.4Q7Flg22 at the same concentration.
Overall, the Syn01Flg22 had higher ROS activity at both concentrations tested in both corn and soy tissues in comparison to Bt.4Q7Flg22 (SEQ ID NO: 226). The shortened 15-amino acid polypeptide Syn01Flg15 was 2-4× more active than Bt.4Q7Flg22 and only slightly less active than the 22-amino acid Syn01Flg22 at 10 nM, indicating that key amino acids for eliciting a plant immune response are retained within the sequence.
Example 47: Chemical Modification to Increase ROS Activity for Flg22 PolypeptidesChemical modifications can be made to Flg22 polypeptides to increase protein stability against proteolysis and/or promote a longer duration of activity that can result in greater availability to the FLS2 receptor. In general, polypeptide modifications can be utilized to 1) stabilize a polypeptide under adverse conditions or in the presence of proteases, or 2) provide additional function or molecular characteristics to the peptide. Modifications for improved stability include polypeptide cyclization and alternations at the N- and C-termini. Head-to-tail cyclization (i.e. amide bond formation between N-terminal amino and C-terminal carboxyl ends) results in a rigid polypeptide backbone that resists conformational changes, often stabilizing peptide-receptor binding and protecting the polypeptide termini from exoproteases. Alternatively, modification of the polypeptide termini can stabilize polypeptides through neutralization (C-terminal amidation) and prevention of N-terminal degradation (N-terminal acetylation). Increased polypeptide solubility and stability can also be conferred through the conjugation of a hydrophilic molecule such as polyethylene glycol (PEG).
Such modifications used to stabilize Flg22 polypeptides include PEGylation, cyclization and amidation/acetylation, all of which are described in Table 71. Stabilization of polypeptides using PEGylation is carried out by linking the polypeptide to polyethylene glycol (PEG). Once linked to the polypeptide, each PEG subunit becomes tightly associated with 2 to 3 water molecules, which then function in increasing the solubility of the polypeptide as well as increasing its overall structure to make it less susceptible to proteolytic degradation and more accessible to the membrane FLS2 receptor at the plant surface. Cyclization can also be used to increase the stability of the Flg polypeptide. Stabilization of a polypeptide can also be obtained using N-terminal acetylation and C-terminus through amidation where these modifications generate a closer mimic of the native protein and therefore may increase the biological activity of the polypeptide.
The specialized, modified polypeptides as described in Table 71 including Syn05Flg22-Syn05 (J36), Syn05Flg22-PEG (J37) and Syn05Flg22-Cyc were synthesized by the University of Missouri Molecular Interactions Core (Columbia, Mo. USA), lyophilized to a dry powder, and determined to be of the correct MW and desired purity (>70%) by liquid chromatography-mass spectrometry (LC-MS) and high-performance liquid chromatography (HPLC), respectively. Standard synthesis polypeptides including Bt.4Q7Flg22 (SEQ ID NO: 226) and Bt.4Q7Flg22 Mod-1 (SEQ ID NO: 226; J41) were obtained from Genscript (Piscataway, N.J. USA). All lyophilized polypeptides were resuspended in ultrapure water to a 10 mM concentration and serially diluted in ultrapure water to the desired concentration for testing in soybean and corn ROS assays as described previously in Example 15.
For soybean samples, fully expanded trifoliate leaves were removed from V1 to V3 stage plants (variety Morsoy). Leaf discs (4 mm) were removed using a cork borer and then floated on 150 μL of water, abaxial side down, overnight before performing the ROS assay previously described.
For corn samples, aerial tissue from V1 to V4 stage corn plants (Beck's hybrid 5828 YX) were prepared as previously described. The 1-mm excised leaf slices were then floated on 150 uL of water overnight.
ROS activity assays were conducted using the methods as previously reported in Example 15 with the exception that Relative light units (RLUs) were recorded with a SpectraMax L luminometer (0.5 s integration; 2.0 min intervals) over a time course of 40 minutes. Relative light units (RLUs) were first plotted over time using a kinetic time course for each concentration tested, followed by integration under the curve to calculate total RLU values produced. Average total RLUs (n=4 samples per treatment) were then graphed versus polypeptide concentration for each polypeptide for soybean (Tables 72-73) and corn (Table 74).
A best fit logarithmic or linear regression (R>0.80) was fit to the data for each treatment. Using the best-fit regression, the polypeptide concentration required to reach a total RLU production of 15,000 total RLU (corn) or a 50,000 total RLU (soybean) was calculated for each polypeptide and % activity was compared within each data set to the control treatment (Tables 72-74).
The Flg22 polypeptide concentration required to result in an RLU output of 50,000 RLU for the Bt.4Q7Flg22S Mod-1 (SEQ ID NO: 226) was less than the current Bt.4Q7Flg22 (SEQ ID NO: 226) that has been shown to produce yield gains and impart plant protective qualities to soybean plants. This indicates that the modification of Flg22 by N-terminal acetylation and/or C-terminal amidation does not interfere with polypeptide binding to the FLS2 receptor, and modifications may be used to produce a more active and/or stable version of Flg22 as indicated by the +6% increase in activity of Bt.4Q7Flg22S Mod-1 over Bt.4Q7Flg22 (Table 72).
Novel polypeptides were generated at the University of Missouri Molecular Interactions Core (Columbia, Mo.) with a single amino acid substitution (A16P) in comparison to the Bt.4Q7Flg22 (SEQ ID NO: 226) unmodified polypeptide, resulting in the Syn05Flg22 (SEQ ID NO: 578) polypeptide which was amenable to further modification by N-terminal PEGylation Syn05Flg22-PEG (SEQ ID NO: 578) and Head-to-Tail cyclization Syn05Flg22-Cyc (SEQ ID NO: 578). A soy ROS assay was performed to assess the effect of these two additional modifications, namely N-terminal PEGylation and Head-to-Tail cyclization to a Flg22 polypeptide, with results shown in Table 73.
In a soy ROS assay to compare the relative activities of Syn05Flg2 (SEQ ID NO: 578) to two modified versions of the polypeptide, the PEGylated polypeptide Syn05Flg22-PEG (SEQ ID NO: 578) required substantially less amount of the polypeptide to achieve a total of 50,000 RLU, which resulted in an increased activity of +38% as compared to the non-PEGylated version or Syn05Flg22 (SEQ ID NO: 578). PEGylation of the N-terminus of the peptide increases the hydrophilicity of the polypeptide and may increase affinity for the peptide-binding pocket of the FLS2 receptor. The cyclized version of Syn05Flg22-Cyc (SEQ ID NO: 578), however, required more polypeptide provided in the ROS activity assay (+57.1 nM more) compared to the non-cyclized version of Syn05Flg22 to reach a total RLU production of 50,000 RLU in the soybean ROS assay. This suggests that the cyclization of the Flg22 polypeptide (Syn05Bt.4Q7Flg22-Cyc) may result in a more rigid polypeptide backbone with altered binding to the FLS2 receptor, such that more cyclized peptide is required to reach an equivalent ROS response. However, increased stability of a cyclized polypeptide in the environment may compensate for the slight loss in activity.
In a corn ROS assay, the PEGylated version of Syn05Flg22-PEG required substantially less amount (almost 5 nM less) of the polypeptide to achieve a total of 15,000 RLU, which resulted in an increased activity of +30% as compared to the non-PEGylated version or Syn05Flg22 (Table 74).
Modification of Flg22 (Bt) or Syn05Flg22 (Bt) polypeptides by N-terminal acetylation, N-terminal PEGylation, C-terminal amidation, and/or head-to-tail cyclization produces a peptide that retains activity, as measured through ROS assays with corn and soy tissues. These polypeptides could be used to deliver a further stabilized Syn05Flg22 (SEQ ID NO: 578) derived polypeptide variant for agricultural uses (either by foliar application, seed treatment, in furrow application, application at transplant, or trunk injection). Cyclization of Syn05Flg22-Cyc may be used to increase the stability of the polypeptide yet compromised the ROS activity, likely by affecting the affinity of the synthetic polypeptide to the membrane FLS2 receptor.
Example 48. Adjuvant Compatibility with Flg22 PolypeptidesProduct formulations using Flg22 polypeptides can generally include antimicrobial biostatic preservatives such as Proxel and surfactants. Therefore, the compatibility of these types of adjuvants were tested using ROS activity assays to determine the effect in solution on Flg22 responsiveness when used in combination with such adjuvants. Proxels in general are broad spectrum biocides for the preservation of many agricultural based products that protect them against spoilage from bacteria, yeast and fungi. Surfactants in general are also commonly used in agricultural formulations to improve the penetration of many agrochemical products into the plant for improved performance. In this study, five different Proxels and two different non-ionic surfactants were tested in formulations combined with Bt.4Q7Flg22 (SEQ ID NO: 226) for effectiveness in producing a ROS response using a ROS activity assay in soybean leaves. The different Proxel formulations (Lonza) are described below in Table 75. Theses Proxel formulations were mixed with 40 μM Flg22 polypeptide at a range of recommended label rates by the manufacturer (Lonza), and then diluted into the ROS assay to a final polypeptide concentration of 100 nM and Proxel concentrations indicated in Table 75. The tested non-ionic surfactants were provided in the ROS assay at a range of recommended label rates by the individual distributer or manufacturer. The average four sample measurements RLU values obtained after performing a ROS assay were collected using soybean leaf disks as previously described in Example 15 with the exception that Relative light units (RLUs) were recorded with a SpectraMax L luminometer (0.5 s integration; 2.0 min intervals) over a time course of 40 minutes. The average of these 4 RLU values is reported in Table 76.
All Proxel preservative treatments as described in Table 76 were compatible when used in formulations with the Flg22 polypeptide (Bt.4Q7Flg22; SEQ ID NO: 226) as indicated by the high RLU values (19.0-28.3× fold increase over mock treatment) as comparable to the Bt.4Q7Flg2 polypeptide control without a Proxel preservative (17.0× fold increase over mock treatment).
All surfactant (non-ionic) treatments as described in Table 77 were compatible when mixed at the indicated concentrations with 52.2 nM Flg22 polypeptide (Bt.4Q7Flg22; SEQ ID NO: 226), a polypeptide concentration equivalent to 4.0 Fl oz/Ac usage rate of Composition 1 (Bt.4Q7Flg22; SEQ ID NO: 226; 16.7 μM) applied in water at a spray rate of 10 gallons per acre. Fold-increase in ROS production over the mock-treated control were comparable between the Bt.4Q7Flg2 polypeptide control without a surfactant (6.8× over control) versus Bt.4Q7Flg2 polypeptide with non-ionic surfactant NIS90:10 applied at 0.25% v/v or 0.5% v/v of treatment solution (5.8-6.4×), or slightly lower for Bt.4Q7Flg2 polypeptide with Silwet-L77 applied at 0.025% v/v or 0.1% v/v of treatment solution (2.8-3.2×). Silwet-L77 (Helena), a non-ionic organosilicone surfactant is formulated as a co-polymer that has enhanced wetting and spreading characteristics when used in aqueous sprays. NIS90:10 (Precision Laboratories) is a low-foaming, non-ionic surfactant that enhances crop protection and performance by improving spray solution coverage and penetration of target leaf surfaces. Both the non-ionic surfactants combined with Bt.4Q7Flg22 permitted ROS production in response to the Flg22 polypeptide in target leaf tissues (Table 77), and as such, are compatible with Flg22 polypeptide foliar application in the field.
Example 49: Production of BL4Q7Flg22 Using Fermentation Methods and Activation by Enterokinase Cleavage for Disease Prevention Trials in Potato, Lentils and Citrus TreesThe Bt.4Q7Flg22 (SEQ ID NO: 226) was provided in a confirmation to stabilize the polypeptide and enhance activity for an alternative production method, namely bacterial fermentation. The Bt.4Q7Flg22 polypeptide was combined with an amyQ secretion signal from Bacillus amyloliquefaciens alpha-amylase) fused to glutathione S-transferase (GST) and an enterokinase cleavage tag sequence as described: amyQ secretion signal (Bacillus amyloliquefaciens alpha-amylase) GST (Schistosoma japonicum)_linker_Enterokinase cleavage site_Bt.4Q7Flg22_stop codon (Table 78).
The sequences in Tables 78, 79 and 80 were cloned into a standard cloning vector containing an ampicillin selection marker and either a chloramphenicol (Cm) or Tetracycline (Tet) selection marker that can replicate in E. coli and then be transferred to Bacillus subtilis strain K08 for production purposes (Production strain codes: H101=amyQ-GST-EK-BtFlg22, H114=amyQ-GST-EK-BtFlg22-Syn01, and H117=amyQ-Thionin-like). The fermentation production was carried out by starting an overnight culture in sterile 2XYT media (16 g Bacto tryptone, 10 g yeast extract, and 5 g NaCl per liter; pH adjusted to 7.0) with 10 μg/mL Cm or Tet, and then diluted into fresh 2XYT media with 10 μg/mL Cm or Tet the following day. Productions were performed using 50 mL (shake flask) or 3 L (glass bioreactor vessel) media volumes with a constant temperature of 30° C. Larger scale up volumes can include 5 L to 1000 L+, including up to 30,000 L volumes). Bacterial growth was monitored until the culture reached an optical density of 0.6-1.0, after which Isopropyl β-D-1-thiogalactopyranoside (IPTG) was added to a final concentration of 0.1-1.0 mM to induce production of the GST-Bt.4Q7Flg22 fusion protein. The induced production continued in culture conditions for an additional 12-24 hours to produce the fusion protein which is secreted into the growth media. Upon secretion, the amyQ secretion tag is cleaved from the fusion protein. The cultures were then centrifuged at 5000×g for 20 min and filtered through a 0.22 μm bottle-top vacuum filter to remove the bacterial cells. The sterile filtrate was then collected and used as a foliar treatment on lentil and potato plants in Sclerotinia disease prevention trials (Example 50) or as a trunk injection of citrus trees for eradication and prevention of HLB disease symptoms (Example 51).
After fermentation, two versions of the Bt.4Q7Flg22 (SEQ ID NO: 226) polypeptide product were used in potato and lentil disease prevention trials, one without enterokinase treatment (H101 filtrate, non-activated) and another with activation using a enterokinase to cleave off the GST tag fused to the Flg22 polypeptide (H101 filtrate EK-activated). To activate Bt.4Q7Flg22, the addition of 32 U (units) of enterokinase (EK: Enterokinase light chain; New England BioLabs, Inc, Product No. P8070) was added per 1 mL of H101 filtrate with an incubation period for 2-3 hours at 30° C. for the enzymatic release of Bt.4Q7Flg22 from the GST-EK cleavage site resulting in an activated and released product comprising the 22 amino acid Bt.4Q7Flg22 polypeptides. For the citrus tree injection trial, H101 filtrate and H114 filtrate were EK-activated with the addition of 0.8 U Enterokinse, light chain (New England Biolabs, Inc, Product No. P8070) per mL of filtrate with an incubation of 3 hours at 30° C. for the enzymatic release of Flg22 polypeptide. No activation treatment was required for release of the thionin-like peptide which was produced without a GST tag.
Example 50: Foliar Pre-Treatment with Bt.4Q7Flg22 Polypeptides Protect Lentil and Potato Plants from Sclerotinia Stem Rot (White Mold) DiseaseTreatment applications of Bt.4Q7Flg22 (SEQ ID NO: 226) were examined for protection of lentil and potato plants against disease infection and progression with Sclerotinia sclerotiorum strain MT07 (white mold). Three different versions of the Bt.4Q7Flg22 polypeptides were examined in the disease assessment studies. A formulated Bt.4Q7Flg22 (100 μM) in sodium phosphate buffer, pH 5.7 and two different versions of Bt.4Q7Flg22 produced using fermentation methods as described (Example 49) and provided with and without activation of Flg22 with an enterokinase (EK) and referred to as H101 filtrate.
Prior to using the three versions of the polypeptides in disease protection assays with lentil and potato plants, a ROS activity assay was performed using corn petiole tissues using methods as described previously in Example 15 to ensure that the Bt.4Q7Flg22H101 filtrate, particularly with the EK was active. The H101 Bt.4Q7Flg22 filtrates without and with enterokinase (EK=8 U/mL filtrate) activation were compared to the synthetic Bt.4Q7Flg22 (SEQ ID NO: 226) which was used to generate a series of concentration comparisons to predict the Flg22 concentrations in the H101 filtrates generated using fermentation procedures.
The fermentation produced H101 filtrates of Bt.4Q7Flg22 provided with and without EK activation bath resulted in ROS activities (RLU values) that were higher than the control (0 nM Bt.4Q7Flg22). The H101 Bt.4Q7Flg22 filtrates (0.1% v/v) with EK treatment provided to corn stem in the ROS assay resulted in a 3.0× increase in RLU values as compared to the control treatment without any Flg22 polypeptide and the ROS response was greater than Bt.4Q7Flg22 (SEQ ID NO: 226) provided at a concentration of 25 nM; therefore, the estimated Bt.4Q7Flg22 activity in the undiluted EK-activated filtrate was Z 25 μM The fermentation produced H101 filtrates of Bt.4Q7Flg22 treatments that were provided without EK still had ROS activity (2.0×RLU) over the negative control treatment but with a lower increase seen in RLU values as compared to the H101 filtrates of Bt.4Q7Flg22 with EK. Once it was confirmed that the H101 filtrates had activity in ROS assays (Table 81) they were assessed in disease protection studies with potato and lentil.
Various formulations of Bt.4Q7Flg22 polypeptides were provided to lentil and potato plants as a foliar pre-treatment to plants 48 hours prior to inoculation with the Sclerotinia sclerotiorum fungus and provided in combination with and without a fungicide (Endura, active ingredient 70% boscalid), which is effective in the treatment and protection of plants from infection with the Sclerotinia fungus (white mold). The Bt.4Q7Flg22 formulations were tested using a crop-disease model (Montana State University, Extension Services Crop Protection) to examine the effects of each of the foliar pre-treatments on the prevention and protection against disease and the development of symptoms. All treatments including the water control were applied to the lentil and potato plants using an air brush connected to a regulated air compressor set with an output pressure to the brush at 50 psi. After the pre-treatment, plants were inoculated with Sclerotinia sclerotiorum using mycelial plug (agar plug covered with mycelium) placed with the mycelia side touching the plant stem and placed in humidity (100%) chambers for a set amount of time.
Lentils
Lentil (variety Pennel) plants were grown in soilless media consisting of a mixture of 1:1 peat moss to perlite in 4′4′ pots with one plant per pot for 24 days in a controlled growth chamber under growth conditions: 300-400 μmol m−2 s−1 (light photons) for a 13/11 light/day cycle and a 21° C. day/15° C. night temperature range. The disease studies included five lentil plants per each of six different foliar treatments with 6 replicate plants per treatment, a total of 30 plants per foliar treatment as described in Table 35. All of the foliar treatments used for pre-treatments were applied with the addition of a non-ionic surfactant (ALLIGARE SURFACE; Alligare, LLC) to a final concentration of 0.1% (v/v) or a concentration of alkylpolyoxethylene, glycol derivatives. Each of the Bt.4Q7Flg22 treatments from the formulated and fermentation-derived productions were provided at an application use rate of 0.1% (v/v) or 300 μL of product to 300 mL water and provided to each plant in an equivalent number of sprays completely covering the foliage, using 8 mL of each treatment application for all 30 plants per treatment. The Endura fungicide pre-treatment was applied at an equivalent application use rate of 11 Fl. oz/Ac (803.8 mL/Ha) following the application instructions on the specimen label. The treatments were randomized using a complete random block design. Approximately 48 hours after the pre-treatment, plants were inoculated with a Sclerotinia sclerotiorum strain isolated locally in Montana using mycelial plug (agar plug covered with mycelium) placed with the mycelia side touching the plant stem. The lentil plants were then placed in humidity (100%) chamber for a period of 72 hours. At 11 days after inoculation disease symptoms were assessed and scored and average fresh weight (total weight of each replicate—grams) were collected (Table 82). Plants were allowed to dry for approximately 3 weeks, and then dry weight was collected (total weight per replicate—grams) (Table 82)
Disease scoring (disease scoring scale 0-7) and fresh weight and dry weight (grams) were collected for each replicate of five plants and then averaged for the total number of plants (n=30). The disease scoring was ranked on a scale of 0-7, with a score of 0 equivalent to no disease and a score of 10 ranked as all plants did not survive (Table 82).
Foliar application of formulated Bt.4Q7Flg22 was compared to the Endura fungicide, the Endura fungicide combined with formulated Bt.4Q7Flg22 and the two Bt.4Q7Flg22 treatments provided with the Flg22 polypeptides produced from the fermentation reactions with and without EK activation as previously described in Table 82. All of the foliar treatments in the crop-disease model were compared to the each other and to water control treated plants and assessed 11 days post inoculation for the appearance of disease symptoms. Each plant was assigned a disease score from 0-7. The total fresh and dry weights (grams) were also determined per plant. The Endura fungicide, a commercially available treatment for Sclerotinia sclerotium resulted in the least disease symptom development on lentil compared across all of the foliar treatments with a disease score of 0.50 whereas, the water treatment (control) resulted in a disease ranking score of 2.83. Foliar application of the formulated Bt.4Q7Flg22 treatment to lentil plants resulted in an increased resistance to Sclerotinia with a disease score of 1.33 (p value=0.0972) compared to plants that received the water control treatment. Unlike the Endura fungicide treatment which resulted in slowed growth compared to the plants treated with the water control, the formulated Bt.4Q7Flg22 treatment resulted in continued vigorous growth during early symptom development. The lentil plants that received the pre-treatment with the formulated Bt.4Q7Flg22 had an average fresh weight of 5.44 grams per plant compared to plants treated with the Endura fungicide alone (2.89 g) or the water control (4.52 g). The combination treatment of the Endura fungicide with the formulated Bt.4Q7Flg22 polypeptide further increased protection of the lentil plants from symptom development with a disease score of 1.0 (p value=0.0524) compared to the plants treated with the water control. Plant weight (fresh and dry) for plants that received the pre-treatment with the formulated Bt.4Q7Flg22 polypeptide was greater than the fresh or dry weights from plants that received the water control or the Endura fungicide alone. The Bt.4Q7Flg22 polypeptides provided from the fermentation derived products (non-EK activated and EK activated) were equivalent in the disease symptom ranking with a disease score of 2.17, which was less than the disease score of plants treated with the water only control application. However, the fresh weight per plant treated with the EK-activated version of the Bt.4Q7Flg22 polypeptide had a significantly increased fresh weight of 6.11 grams (p value=0.0266) as compared to the water treated plants. The EK-activated version of the Bt.4Q7Flg22 polypeptide also had the overall highest fresh and dry weights compared to all of the other treatments in Table 82. Other significant findings of this study were that the formulated Bt.4Q7Flg22 polypeptide pre-treatment of lentil plants protected the lentils from fungicide-induced damage. The average fresh weight of the plants that received the Endura fungicide was 2.89 g while the formulated Bt.4Q7Flg22 treatment was 5.44 g (p value=2.645×10-05). The fermentation produced Bt.4Q7Flg22 containing the enterokinase (EK) enzyme was used to cleave the Bt.4Q7Flg22 polypeptide from the GST-EK-Bt.4Q7Flg22 as previously described. This Bt.4Q7Flg22 filtrate treatment provided to lentil increased activity of the Flg22 polypeptide thus resulting in significantly enhanced plant growth during the infection period compared to the water treated control plants (p value=1.180×10-05). The non-activated EK or GST-EK-Bt.4Q7Flg22 or non-cleaved Bt.4Q7Flg22 filtrate did not increase plant growth compared to the plants that received the water control only treatment (p value=0.9852).
Potatoes
Seed potatoes (variety: Russet Burbank) were planted from 2 cm potato sections from which eye buds protrude (1 section per pot) with the cut side down and planted approximately 7-8 cm deep in soilless media consisting of a mixture of 1:1 peat moss to perlite in 10×10 cm pots. Potatoes were grown with one plant per pot for 19 days in a controlled growth chamber under standard conditions of receiving approximately 300-400 μmol m−2 s−1 (light photons) for a 13/11 light/day cycle and a 21° C. day/15° C. night temperature range. 19 days after planting, the potato plants were pre-treated with the foliar applications as described in Table 36. The disease studies included five potato plants per each of six different foliar treatments with 6 replicate plants per treatment, a total of 30 plants per foliar treatment as described in Table 83. All of the foliar treatments used for pre-treatments were foliar applied with the addition of a non-ionic surfactant (ALLIGARE SURFACE; Alligare LLC) to a final concentration of 0.1% (v/v) or a concentration of alkylpolyoxethylene, glycol derivatives. Each of the Bt.4Q7Flg22 treatments from the formulated and fermentation derived productions were provided at an application use rate of 0.1% (v/v) or 300 μL of product to 300 mL water and provided to each plant in an equivalent number of sprays completely covering the foliage using 15 mL of each treatment application for all 30 plants per treatment. The Endura fungicide pre-treatment was applied at an equivalent application use rate of 11 Fl. oz/Ac (803.8 mL/Ha) following the application instructions on the specimen label. The treatments were randomized using a complete random block design. Approximately 48 hours after the pre-treatment, plants were inoculated with Sclerotinia sclerotiorum using mycelial plug (agar plug covered with mycelium) placed with the mycelia side touching the plant stem and placed in a humid chamber (100%) for 192 hours. At 16 days after inoculation disease symptoms were assessed and scored and average stem fresh weight (total stem weight—grams) were collected (Table 83). Plants were allowed to dry for 12 days, and then dry weights were recorded (total stem weight—grams) (Table 83).
After 48 hours, the potato plants were inoculated with mycelia plugs placed on the soil near each plant and placed in a humid misting chamber. The treatments were randomized using a random block design. Disease scoring (scoring scale 0-6). Stem fresh and dry weight (grams) were also collected from each plant and then averaged for the total number of plants (n=30). Stem dry weight was taken after the plants were fully desiccated at approximately 12 days after harvest. Disease scores were assessed 16 days after the initial inoculation. The disease scoring was ranked on a scale of 0-6, with a score of 0 equivalent to no disease and a score of 6 ranked as all plants did not survive.
Foliar pre-treatment applications using the formulated Bt.4Q7Flg22 and Bt.4Q7Flg22 polypeptides derived from the fermentation products (H101 filtrates) were compared for disease symptom development on potato plants that received the Endura fungicide and the water control treatment. Foliar application of formulated Bt.4Q7Flg22 (SEQ ID NO: 226) provided as a pre-treatment to potato plants resulted in a disease score of 1.83 as compared to plants that received the water control (disease score=2.83). Plants that received pre-treatment with the Endura fungicide had the least disease symptoms with a disease score of 0.50 (p value=0.0045) compared to plants treated with the water control. The formulated Bt.4Q7Flg22 polypeptide pre-treatment resulted in plants with an average disease score similar to the enterokinase activated Bt.4Q7Flg22 (H101 EK-activated) provided in a filtrate (fermentation product)—both had disease scores of 1.83. The non-activated EK or GST-EK-Bt.4Q7Flg22 or non-cleaved Flg22 filtrate (H101 non-activated) provided to plants had a score of 2.33 and was not significantly different from the disease score of plants that were treated with the water control (p value=0.4835). However, potato plants that received the pre-treatment with the EK-activated Bt.4Q7Flg22 filtrate resulted in an increased average stem fresh and dry weight per plant compared across all treatments with approximately a 20 g increase in stem fresh weight and an almost 6 g increase in stem dry weight per plant compared to plants that received the water control pre-treatment. Plants that received the formulated Bt.4Q7Flg22 polypeptide all had increased stem fresh and dry weight as measured on a per plant basis compared to plants that received the water only control application.
Example 51: Treatment of Candidatus Liberibacter asiaticus infection with Flg22 and Anti-Microbial PolypeptidesBt.4Q7Flg22 formulations were applied by trunk injection treatments to both Valencia orange (Citrus sinensis) and Ruby Red grapefruit (Citrus x paradisi) trees. The study was conducted at a commercial grove orchard located in central Florida (Okeechobee county). Injection treatment using the Bt.4Q7Flg22 polypeptide (SEQ ID NO: 226) provided using a 1× Low Rate (0.55 micromoles peptide; 0.138 μM estimated concentration in phloem) and a 10× High Rate (5.5 micromoles peptide; 1.38 μM estimated concentration in phloem) was compared to the non-treated control trees. The injection treatments were set up using a randomized complete block design with 10 grapefruit trees (4 years old) per treatment. The injections were provided in April (2017) at first flush, a stage in growth from the emergence of leaves until they expand to full size. Injection of grapefruit trees were conducted using a low-pressure injection device, BRANDTENTREE (BRANDT). Leaves from each of the grapefruit trees were sampled at the time of injection (Day 0), 21 and 56 days post injection. A total of six leaf samples per tree were selected to represent the population of leaves on the tree in terms of leaf age, location, and presence of visual symptoms. Each midrib was separated from the leaf blade and immediately chopped into very small pieces with a new sterile razor blade. Leaf samples from each tree were then placed in an individual tube that was subsequently stored in a freezer at −80° C. until further processing. DNA extraction and real-time polymerase chain reaction or quantitative PCR (qPCR) analysis on these leaves was performed at Southern Gardens Citrus (Clewiston, Fla.).
The presences of the CLas bacterial titers in the HLB infected citrus trees can be determined with quantitative real-time polymerase chain reaction (qPCR) methods using specific primers to confirm the presence of the disease (Li, W. B., Hartung, J. S. and Levy, L. 2008 “Optimized quantification of unculturable ‘Candidatus Liberibacter spp.’ In host plants using real-time PCR”, Plant Disease 92: 854-861). DNA extraction and quantitative PCR (qPCR) analysis on these leaves was performed at Southern Gardens Citrus (Clewiston, Fla.) using HLB primer set targeting the 16S DNA of C. liberibacter bacteria 5′>>3′ (forward): HLB as TCGAGCGCGTATGCAATACG (SEQ ID NO: 773); (reverse) HLBr: GCGTTATCCCGTAGAAAAAGGTAG (SEQ ID NO: 774); HLBpc (probe): AGACGGFTGAGTAACGCG (SEQ ID NO: 775) labeled with an intercalating fluorescent reporter dye]. Forty cycles of qPCR were conducted and the fluorescent signal which is proportional to the amount of dsDNA in solution was measured. The qPCR analysis allows for the detection of the CLas bacteria in citrus tissue. The cycle threshold (Ct) values from the qPCR analysis were obtained per each treatment. The Ct measurement is equivalent to the number of PCR cycles required to produce a relative threshold level. As in common practice within the field of molecular biology, the change in Ct value is reported to indicate the relative quantity of CLas DNA either in treated vs untreated samples or in treated samples at one time point vs another time. The higher the Ct value, the greater or more effective the treatment effect, which is indicated by the reduction/elimination of CLas bacteria from the tree. A percentage reduction in bacterial load can be computed as:
The results from the grapefruit trial are shown in
In another study using Valencia orange (Citrus sinensis) also conducted at the commercial grove orchard located in central Florida (Okeechobee county). Injection treatments using formulations of Bt.4QFlg22 (SEQ ID NO: 226) were compared to antimicrobial polypeptides known as thionins. Thionin injection was provided as a mixture of thionin polypeptides (SEQ ID NOs: 651, 652 and 653) which are characterized as “un-tagged” or without a phloem localization sequence. In addition to the un-tagged thionin mixture, a “tagged” thionin polypeptide that comprised a phloem localization sequence (SEQ ID NO: 650) was used as a comparative injection treatment. The phloem targeted or “tagged” version was used to target the thionin specifically to the phloem where CLas bacteria reside and multiply. The injection treatments were applied to orange trees using a randomized complete block design with a total of 8 orange trees (8 years old) per treatment for the untreated control and Bt.4QFlg22 treatments, and a total of 5 orange trees per treatment for the thionin treatments. The injections were provided in April (2017) at first flush, a stage in growth from the emergence of leaves until they expand to full size. Injection of the orange trees were conducted using a low-pressure injection device, BRANDTENTREE (BRANDT). The Bt.4Q7Flg22 polypeptide 1× (0.138 μM) and a 10× (1.37 μM) concentrations, the “untagged” and the “tagged” thionin polypeptides were all compared to trees that received no injection treatment (control). Leaves from the orange trees were sampled per each treatment at the time of injection (Day 0) and at T56, or 56 days post injection.
A total of six leaf samples per tree, were selected to represent the population of leaves on the tree in terms of leaf age, location, and presence of visual symptoms. Each midrib was separated from the leaf blade and immediately chopped into very small pieces with a new sterile razor blade. Leaf samples from each tree were then placed in an individual tube that was subsequently stored in a freezer at −80° C. until further processing. DNA extraction and real-time polymerase chain reaction or quantitative PCR (qPCR) analysis on these leaves was performed at Southern Gardens Citrus (Clewiston, Fla.) using the methods as described above for performing Ct analysis.
Results from the Valencia orange trial are shown in
The Bt.4Q7Flg22 polypeptides provided as injection treatments using final concentrations at the 1× (0.138 μM) and 10× (1.38 μM) were both effective in reducing CLas titer levels in the leaf tissue sampled 8 weeks post injection. The higher concentration of the Bt.4Q7Flg22 polypeptide 10× (1.38 μM) however was even more effective resulting in a 37% reduction (Trial 1) and a 43% reduction (Trial 2) in CLas titer levels.
Previous results indicate that Bt.4Q7Flg22 (SEQ ID NO: 226) promotes plant growth throughout periods of disease (Example 50). To assess for a potential plant growth benefit to injecting HLB-infected ‘Valencia’ Orange and ‘Ruby Red’ Grapefruit trees with Bt.4Q7Flg22 (SEQ ID NO: 226), current year growth was measured in May 2018 for the same trees that were injected with Bt.4Q7Flg22 in April 2017 and assessed for CLas bacterial titer at the commercial grove orchard located in central Florida (Okeechobee county). Each tree was visually assessed for regions of current season growth with green color to the branches, as compared to old growth branches that are more woody in appearance with a dark greenish-brown to brown hue. Three representative branches with new growth were selected per tree, and the distance in inches from the start of green growth (oldest node) to the tip of the youngest node was measured with a flexible measuring tape. Data was collected for trees injected with 1× and 10×Bt.4Q7Flg22 (SEQ ID NO: 226) as well as the untreated control, with 8 trees per treatment for the ‘Valencia’ orange trial and 9-10 trees per treatment for the ‘Ruby Red’ Grapefruit trial (n=24-30 measurements per treatment). Only one tree in the ‘Ruby Red’ Grapefruit trial was lost from the original trial (1× Bt.4Q7Flg22 treatment group), presumably due to hurricane-strength wind damage in September 2017. For each trial, the average new growth length (inches) was calculated and normalized to the untreated control (Table 85).
These results demonstrate the ability of Flg22 compositions, which displayed reduced CLas bacterial titer compared to untreated plants (
As these plants were not 100% cleared of disease-causing bacteria, these results also demonstrate the ability of the plants injected with Bt.4Q7Flg22 to continue to grow despite the presence of HLB-causing bacteria. Provided that CLas strains with antibiotic resistance are predicted to emerge and become an additional hurdle for HLB-control, Flg22 injection represents a desirable alternative to antibiotic treatments for ameliorating plant growth and reducing bacterial titer. The trees receiving the Flg22 injections in this example were maintained with a standard commercial citrus treatment program, which further demonstrates the ability to add Flg22 citrus injections to standard grower practices.
Example 52: Foliar and Trunk Injection of Flg22 Applied Alone or in Combination with Antimicrobial or Plant-Health Promoting Compounds Increase New Shoot Growth in Orange TreesIn subsequent trials in April (2018), Flg22 formulations were applied by trunk injection treatments or foliar spray at two independent trial sites. Trials were designed to 1) test Flg22 polypeptide variants produced synthetically and by fermentation, 2) compare the efficacy of the Flg22 variant previously used for citrus injection trials in 2017, Bt.4Q7Flg22 (SEQ ID NO: 226), versus Syn01Bt.4Q7Flg22 (SEQ ID NO: 571) which was effective as both a foliar and seed treatment for increasing yield in row crops, 3) compare Flg22 application methods, namely trunk injection versus foliar spray to the canopy, and 4) test combinatorial treatments between Flg22 peptides and oxytetracycline injection, L-cysteine, and Benzo (1,2,3) thiadiazole-7-carbothioic acid-S-methyl ester (also known as BTH) as the commercially available formulation ACTIGARD WG. L-cysteine is an essential, proteinogenic amino acid; and BTH is a salicylic acid analog with increased stability that is used agriculturally as an activator of plant immune responses and is approved for application to citrus trees as root drench or irrigation treatment to prevent citrus canker caused by Xanthomonas axonopodis pv citri.
In March 2018, trees were treated at two separate sites. Three-year old Hamlin orange trees (Citrus sinensis) were treated at a commercial grove orchard located in central Florida (Okeechobee County). A similar trial was conducted in a commercial grove of 6-year old Vemia orange trees on Swingle rootstock at Lake Wales, Fla. (Polk County). Treatments were applied as listed in Table 85 below using a low-pressure injection device, BRANDT ENTREE (BRANDT) for trunk injection or a CO2-pressurized backpack sprayer that produced a fine mist for foliar spray. Trunk injections were as described in Example 51. Foliar compositions of Bt.4Q7Flg22 were diluted in water with a non-ionic surfactant (Precision Labs NIS90:10; 0.1% v/v of spray tank volume) and evenly applied to the canopy of the tree at a spray rate of 3 Liters per tree. Blocks of trees receiving a foliar treatment were spaced in the trial area with a gap (skipped tree) in between treatment blocks to avoid drift of treatment into neighboring treatment blocks. Treatments were applied during the early morning or late evening during a period of low wind (<5 mph), and conditions were such all spray treatments dried on leaves within a period of 4 hours. Combination treatments described in Table 86 were either co-injected in the same BRANDT ENTREE battle (Citrus Composition 7, Citrus Composition 8) or applied separately as an oxytetracycline injection followed by a Bt.4Q7Flg22-Syn01 foliar treatment on the same day (Citrus Composition 11, Citrus Composition 12). For all treatments, 10 trees were used per treatment, separated into two replicated blocks of five trees each. Citrus compositions 1-8 were applied at bath the Okeechobee and Polk County groves, while Citrus Compositions 9-12 were applied at Okeechobee grove alone.
To assess for a potential plant growth benefit to injecting or spraying HLB-infected orange trees with different formulations of Flg22 polypeptides alone or in combination with antimicrobial or plant-health promoting compounds, new flush length was measured in May 2018 for trees that were treated in March 2018 at commercial groves in Okeechobee county, FL and Polk county, FL. At the time of treating plants at both locations (March 2018), trees exhibited darker green leaves with 2018 season fruit beginning to develop. In the two-month interval between treatment (March 2018) and the time of tree measurement (May 2018), trees entered a period of spring flush with new growth visible as very light green, flexible branches with similarly light green leaves. Each tree was assessed for new flush, and three representative branches with new growth were selected per tree. The distance in inches from the start of light green growth (oldest node) to the tip of the youngest node was measured with a flexible measuring tape. Data was collected for 10 trees per treatment including the untreated control, for a total of 30 measurements per treatment. Represented in Table 86 is the average flush length (inches) for each treatment across the two grove sites in Okeechobee and Polk counties, with growth normalized to the untreated control.
Growth measurements of ‘Hamlin’ and ‘Vemia’ new shoots, taken two months after either trunk injection or foliar spray application of Flg22 variants, indicated that Bt.4Q7Flg22 (SEQ ID NO: 226) and Syn01Flg22 (SEQ ID NO: 571) are both effective at promoting greater growth than the untreated control. On average, untreated control shoots were 3.08 inches in length, while Bt.4Q7Flg22-injected trees had 25% longer shoots (3.84 inches) and Syn01Flg22 injected trees 146% longer shoots (4.48 inches). Bt.4Q7Flg22 and Syn01Flg22 produced through fermentation methods described in Example 49 were also effective at increasing shoot growth when injected into the trunk at a rate of 80 mL/tree. Citrus composition 3 containing Bt.4Q7Flg22 produced by fermentation of strain H101 and treated with 0.8 U/mL Enterokinase (New England Biolabs; Product Code P8070) was the most effective, with shoots measuring on average 169% (5.18 inches) longer than the untreated control.
Foliar application of Flg22 variants, which is effective for promoting growth of kiwi, soy, lentils, and potatoes under disease pressure were also tested for the ability to promote growth of HLB-infected orange trees. Table 88 shows that Citrus Compositions 5 and 6 comprised of a 1× or 4× dose of Syn01Bt.4Q7Flg22 (SEQ ID NO: 571), respectively, are also effective at promoting new shoot growth in orange trees. The 1× and 4× doses were similarly effective, with the 1× foliar rate measuring 119% longer shoots than the control, and the 4× rate measuring 122% longer shoots than the control. These results show that a foliar application of Flg22 polypeptide can be used as part of a standard program of care of citrus grove trees.
Next, the combination of Syn01Bt.4QFlg22 (SEQ ID NO: 571) with BTH (ACTIGARD WG) or L-cysteine was investigated at both the Melvin locations and Lake Wales groves. Both combination treatments in Table 88 showed greater new flush length in comparison to the untreated control, showing that Flg22 polypeptides can be used in combination with amino acids, plant hormones, or plant hormone-mimics to improve citrus tree health.
In a separate trial, the combination of Syn01Flg22 (SEQ ID NO: 571) and oxytetracycline treatments were observed. On the same day that trees were injected with oxytetracycline, groups of 10 trees were also sprayed with a foliar application of Syn01Flg22 at a 1× rate or 10× rate. These results show that the antibiotic and polypeptide treatments are compatible and that no phytoxicity was observed due to the dual treatment. A standard program could be envisioned where grower alternated tree injections with foliar treatments for enhanced control of HLB symptoms and for reducing CLas titer.
Example 53: Disease Protection Using Bt.4Q7Flg22 and Gm.RHPP Foliar Applications on Soybean Plants to Protect from Diseases Caused by Phakopsora Pachyrhizi and Cercospora KikuchiiTable 90 describes the compositions and corresponding use rates tested in the following example.
Replicated field trials were conducted across three locations in Paraguay (Yatytay, Obligado, and Capitcn Miranda) using a foliar application comprising a compositions of the Bt.4Q7Flg22 polypeptide and RHPP polypeptide provided with a broad-spectrum fungicide, Fox (16.0% prothioconazole and 13.7% thiofloxystrobin). FOX is a commercially available foliar fungicide in South America with limited efficacy for preventative and curative treatment of Asian soybean rust caused by Phakopsora pachyrhizi and Cercospora leaf blight of soybean caused by Cercospora kikuchii applied as a foliar spray following the recommendations on the specimen label at a use rate of 5.48 fluid ounces per acre (Fl. oz/Ac) (400 mL/hectare). Beginning at the R1 stage of development, soybean plants received two foliar applications of the compositions described in Table 90 with an interval of 13-14 days between spray applications. Foliar treatments were applied to a single soy variety (which one? Same at all 3 sites) at the three sites, with 4 replicated plots (3×10 meters, 30 m2; with minimum of 6 rows per treatment). Disease assessments for trials that were naturally infected were scored for the severity of infection (0-100% of foliage affected) were scored for 10 plants within each plot for both Asian soybean rust caused by Phakopsora pachyrhizi and Cercospora leaf blight of soybean caused by Cercospora kikuchii at the R4-R5 stage of soy development (4-15 days after second foliar application) with guidance from Godoy et al (1997; Journal of plant diseases and protection 104:336-345). Percent phytotoxicity (0-100% of foliage affected) was also scored at the R4-R5 stage of soy development. Severity of infection and phytotoxicity were averaged across all four replicates per site (Total=12 replicates, 3 sites with 4 replicates each). Standard deviation for each treatment between the three sites was calculated. Untreated control plants at the Yatytay site displayed 99% defoliation at 11 days post-application of the second foliar treatment and were scored for defoliation (0-100% defoliated) at this time. Disease severity, phytotoxicity, and defoliation results are provided in Table 91 as percentages, with standard deviation in parentheses.
Foliar application of Bt.4Q7Flg22 and Gm.RHPP during reproductive phases of soy development provided increased protection against Asian soybean rust and Cercospora leaf blight as compared to the untreated control. Foliar applications of Bt.4Q7Flg22-treated plants at 150 and 300 mL/Ha displayed 12.4-13.0% less Asian soybean rust leaf area damage and 2.8-3.5% less Cercospora leaf area damage compared to the untreated control; and foliar applications of Gm.RHPP-treated plants at 150 and 300 mL/Ha displayed 10.5-11.3% less Asian soybean rust leaf area damage and 3.3-4.5% less Cercospora leaf area damage compared to the untreated control. Combination treatments including either Bt.4Q7Flg22 or RHPP with FOX fungicide increased protection against Asian Soybean Rust and Cercospora relative to the Fox Fungicide treatment alone. At the Yatytay site, less defoliation was observed at the R7 stage of development due to severe disease symptoms upon Bt.4Q7Flg22 or Gm.RHPP treatments+/−FOX fungicide. While the untreated control was 99% defoliated at this stage, Bt.4Q7Flg22 treatment at 150 or 300 mL/Ha decreased defoliation to 70 or 60% with green leaves still visible, respectively. The Gm.RHPP treatment at 150 or 300 mL/Ha decreased defoliation to 96% or 70%, respectively. Combination treatment with Bt.4Q7Flg22 or Gm.RHPP treatments with FOX fungicide decreased defoliation to 25% with green leaves visible, while Fox fungicide alone decreased defoliation to only 45% without green leaves visible. Overall, polypeptide treatments provided increased protection over FOX Fungicide alone for control of Asian soybean rust and Cercospora leaf blight. No phytotoxicity was observed for any polypeptide application alone, and combination of either polypeptide with FOX fungicide neither significantly increased or decreased phytotoxicity relative to the FOX Fungicide alone (Table 93).
Example 54. Flg22-PSA Foliar Application on Kiwi Protects Plants from Pseudomonas syringae pv. actinidiae (PSA-V)Pseudomonas syringae pv. actinidiae (PSA) is a devastating plant pathogen causing bacterial canker of both green- (Actinidiae deliciosa) and yellow-flesh (Actinidiae chinesis) kiwi plants throughout zones of kiwi production, causing severe harvest loss in New Zealand, China, and Italy. In New Zealand alone, cumulative revenue losses to the most devastating biovar PSA-V are predicted to approach $740 million New Zealand leaves Dollars (NZD) by 2025 (Agribusiness and Economics Research Institute of Lincoln University “The Costs of Psa-V to the New Zealand Kiwifruit Industry and the Wider Community”; May 2012). PSA-V colonizes the outer and inner surfaces of the kiwi plant and can spread through the xylem and phloem tissues. Disease symptoms of PSA-V on kiwi include bacterial leaf spot, bacterial canker of the trunk, red exudates, blossom rot, discoloration of twigs, and ultimately dieback of kiwi vines. The standard method of control for PSA-V currently employs frequent foliar applications of metallic copper to kiwi vines which is predicted to lead to the selection of copper-resistant form of the pathogen and loss of disease control. Novel methods of control are urgently needed.
To test the sensitivity of kiwi leaves to 22-amino acid fragments of flagellin, 1 mm slices were cut through Actinidiae deliciosa Kiwi ‘Hayward’ leaf petioles and floated in 150 μL of water in a 96-well plate, with one slice per well. Flg22 polypeptides in Table 94 were prepared for the assay by re-suspending lyophilized polypeptide in deionized water to a concentration of 10 mM; peptides were then serially diluted to 10 μM in 100 mM sodium phosphate (pH 7.8-8.0) buffer with 0.1% Tween-20. Water was removed from kiwi leaf petiole samples after 20 hours and replaced with 100 μL of an elicitation solution containing 100 nM peptide (diluted from 10 μM stock), 34 μg/mL luminol, and 20 μg/mL horseradish peroxidase in deionized water. Recognition of the Flg22 polypeptide by the plant tissue resulted in activation of immune signaling and the production of apoplastic reactive oxygen species (ROS). In the presence of ROS (H2O2), horseradish peroxidase catalyzed the oxidation of luminol and production of visible light. Relative light units (RLUs) were recorded with a SpectraMax L luminometer (0.5 s integration; 2.0 min intervals) over a time course of 40 minutes. In two independent experiments, a total of 6 kiwi leaf petiole samples were treated with each Flg22 polypeptide in Table 94. The average total RLU and standard error of the means (SEM) was calculated for each treatment. A two-tailed T-test was used to determine significance at the 90% confidence level (P<0.1) between treatments. Relative ROS production was determined for each polypeptide in comparison to total RLUs for the 100 nM Bt.4Q7Flg22 control.
Across two independent experiments Kiwi ‘Hayward’ leaf petioles were significantly more sensitive to Flg22 derived from Pseudomonas syringae pv. actinidiae (Flg22-PSA; SEQ ID NO:540) in comparison to Flg22 derived from Bacillus thuringiensis strain 4Q7 (Bt.4Q7Flg22; SEQ ID NO: 226). While ROS production was increased in kiwi leaf petioles in response to the synthetic Syn01Flg22 (SEQ ID NO: 571) in comparison to Bt.4Q7 Flg22 (SEQ ID NO: 226) the difference was not significant. Based on these results, Flg22-PSA (SEQ ID NO: 540) was formulated as indicated at 100 nM final concentration (Table 94) for disease prevention trials in potted Kiwi ‘Hayward’ plants in New Zealand.
Foliar compositions contained 0.1% (v/v) PROXEL BC preservative, an aqueous dispersion of a blend of 330.7 mM 1,2-benzisothiazolin (BIT), 53.5 mM 5-chloro-2-methyl-4-isolthiazolin-3-one (CMIT), and 26.1 mM 2-methyl-4-isothiazolin-3-one (MIT). Foliar compositions were diluted to the indicated concentrations in water (g/L water or mL/L water) with 0.05% (v/v) Contact Xcel™ non-ionic surfactant. The diluted products were applied in fine droplets with a pressurized backpack sprayer to the entire canopy of each plant, until thoroughly covered.
To assess the efficacy of Flg22-PSA (SEQ ID NO: 540) for control of Pseudomonas syringae pv. actinidiae (PSA-V), a potted kiwi disease trial was conducted in the Bay of Plenty area of New Zealand by HortEvaluation Ltd in collaboration with NuFarm Limited. PSA-V symptom-free potted kiwi Actinidiae deliciosa ‘Hayward’ plants were evenly distributed between the 6 treatment groups, with 12 potted plants per group. One day prior to inoculation with PSA-V, potted plants were treated with ChampION++™, the industry standard for PSA-V control, or formulated Flg22-PSA according to the application rates in Table 96 (Treatment groups 3,4) at a plant nursery in Te Puka, New Zealand. After 24 hours, all plants except for the uninfected controls were sprayed with 1×108 cfu/mL PSA-V inoculum using a 5 L hand-held pressurized sprayer aimed at the underside of leaves until thoroughly covered. The uninfected control was sprayed with water alone. Potted plants were then transported to Pukehina and placed in an area with overhead misting for 48 hours to mimic environmental conditions for PSA-V infection, with uninfected control plants separated from infected plants. After 48 hours, a subset of plants was then removed from the misting area and allowed to briefly dry. After the final treatments, all plants were moved to their final outdoor trial site, randomized positions in Pukehina. Average daily temperature at the trial site was 20.75° C. with a total rainfall of 277 mm over 34 days. Additionally, each plant was watered twice a day for two hours at a time by drip irrigation. Environmental conditions were favorable for progression of PSA-V disease symptoms. Plants were visually monitored throughout the trial period for PSA-V disease assessments, with the same assessor recording the % of leaf area covered in spots at 6 days after inoculation (6 DAI), 16 DAI, 23 DAI and 29 DAI. Additionally, each plant was assessed for treatment phytotoxicity effects at 29 DAI on a scale of 0-10, with 0=no leaf phytotoxicity and 10=very severe leaf phytotoxicity symptoms. The average disease scores at 6, 16, 23, and 29 DAI and phytotoxicity score at 29 DAI are reported in Table 96 for each treatment (n=12 plants per treatment). P-values were calculated for each treatment vs. the untreated control.
Application of Flg22-PSA significantly reduced PSA-V leaf spot symptoms (P<0.1; 90% confidence interval) at 6, 16 and 23 DAI in comparison to the untreated control. Combination of Flg22-PSA pre-treatment further decreased the severity of leaf spot compared to Flg22-PSA treatment alone at all assessment timepoints and prolongs the period of significant protection to 29 DAI (14.3% less leaf spot compared to untreated control; P=0.002). In conclusion, Flg22-PSA can be used both as a stand-alone treatment and in combination with other treatments aimed at restricting pathogen growth. While the industry standard ChampION++™ which is the currently used copper containing treatment to treat PSA causes mild leaf phytotoxicity (AVE score=1.6), no significant phytotoxicity was observed for Treatments 3-4 (Table 97). Flg22-PSA can be used as an alternative to other phytotoxic treatments.
Elf18 and Elf26 polypeptides derived from the consensus Bacillus cereus Elongation Factor-TU (EF-Tu) protein were tested for ability to produce a ROS response in corn (hybrid 5828 YX), soy (variety Morsoy), and Arabidopsis thaliana. Polypeptides were synthesized by Genscript USA (Piscataway, N.J.) using standard solid-phase synthesis methods and provided as a lyophilized powder with greater than or equal to 70% purity. Dry powder was re-suspended to a concentration of 10 mM in ultrapure water, and then serially diluted in ultrapure water to the concentrations tested in the ROS assay in Table 98.
For the ROS assay, Arabidopsis leaves were excised from 4-week-old plants, and using a cork borer 4 mm disks were removed from the leaves. Each disc was cut in half using the edge of a razor blade, and then each disc half was floated on 150 μL of water abaxial side touching the water in a 96-well plate to rest overnight. The next day, the water was removed from each well just prior to polypeptide treatment. RLU values and relative ROS activity was reported as the average of 4 measurements. ROS activity assays were conducted using the methods as previously reported in Example 15). ROS activity results are reported in Table 97 below.
The receptor for EF-Tu polypeptides, EF-Tu Receptor (EFR) was previously identified in the Brassica clade, of which Arabidsopis thaliana is a model plant. Results in Table 99 indicate that newly identified polypeptides from Bacillus cereus EF-Tu (SEQ ID NO: 616 and SEQ ID NO: 617) can be used to elicit a ROS response similar in magnitude to Bt.4Q7Flg22 (SEQ ID NO: 226) when each was tested at a 100 nM concentration. In comparison to the mock-treated control, EF-Tu N-terminal polypeptides gave a response that was 3.2- to 2.5-fold increased, while Bt.4Q7Flg22 was 3.1-fold increased over mock control. These results suggest that 18- and 26-amino acid fragments from the N-terminus of Bacillus cereus can be used similarly to Bt.4Q7Flg22 in the Brassica crops, including but not limited to kale, cabbage, collard greens, cauliflower, Brussel sprouts, savoy, kohlrabi and gai lan, to increase plant biomass, yield and disease prevention.
Combination treatments of EF-Tu N-terminal peptides (SEQ ID NO: 616 and SEQ ID NO: 617) and Bt.4Q7Flg22 (SEQ ID NO: 226) resulted in similar ROS responses to the EF-Tu peptides alone, indicating that the combination of peptides treatments in the field would provide no interference of activity; however, due to the shared mechanisms between downstream signaling events for EF-Tu and Flg22 peptides, recognized by the EFR and FLS2 receptors respectively, a staggered application of peptide treatments may provide the greatest growth benefit to the plant.
Example 56: Disease Protection using Bt.4Q7Flg22 and Gm.RHPP Foliar Applications on Soybean Plants to Protect from Diseases Caused by Phakopsora pachyrhizi and Cercospora kikuchiiFoliar application of Bt.4Q7Flg22 (SEQ ID NO: 226) and Gm.RHPP (SEQ ID NO: 600) during reproductive phases of soy development was previously found to decrease disease symptoms caused by Phakopsora pachyrhizi and Cercospora kikuchii infections (Example 53). These plants were taken to yield, and Bt.4Q7Flg22 (SEQ ID NO: 226) and Gm.RHPP (SEQ ID NO: 600) foliar applications were found to increase yield in comparison to the untreated control plants in replicated trials in Paraguay where plants were infected with Asian soybean rust and Cercospora leaf blight. Foliar applications of Bt.4Q7Flg22 at 150 and 300 mL/Ha increased yield by +342.2 kg/Ha and +427.2 kg/Ha, respectively, in trials where the average yield for untreated plants was 1266.3 Kg/Ha. The increase in yield for 300 mL/Ha foliar application of Bt.4Q7Flg22 (36.1%) was comparable to FOX Fungicide alone (36.6%), demonstrating that Bt.4Q7Flg22 is effective as an anti-fungal foliar treatment for both reducing disease symptoms and boosting yield. The relative yield across all three trial sites was for plants treated with a combined application of FOX Fungicide and Bt.4Q7Flg22 was slightly increased over FOX fungicide or Bt.4Q7Flg22 foliar application alone, demonstrating that the treatments are compatible. Foliar applications of Gm.RHPP at 150 and 300 mL/Ha further increased yield by +294.2 kg/Ha and 506.8 kg/Ha, respectively, in comparison to the untreated control. When applied in combination with FOX Fungicide, Gm.RHPP provided the greatest protection against disease in the trials as evidenced by increased yield of +517.6 kg/Ha and +539.9 kg/Ha for the 150 mL/Ha and 300 mL/Ha application rates of Gm.RHPP, respectively. Foliar application of Gm.RHPP consistently improved plant health and increased yield, thus Gm.RHPP is an effective treatment for growth promotion and fungal disease resistance.
Previous results summarized in Example 51 indicate that Bt.4Q7Flg22 (SEQ ID NO: 226) trunk injection reduces pathogen titer and promotes new growth in citrus trees infected with Candidatus Liberibacter asiaticus, the causative agent of Huanglongbing (HLB). To assess for a potential increase in fruiting and obtain early estimates of yield, fruit set was measured in June 2018 for the same HLB-infected ‘Valencia’ Orange (to be harvested spring 2019) and ‘Ruby Red’ Grapefruit trees (to be harvested fall 2018) that were trunk-injected with Bt.4Q7Flg22 in April 2017 at the commercial grove orchard located in central Florida (Okeechobee county). As described in Example 51, trees were injected in April 2017 with either a 1×Bt.4Q7Flg22-Low Rate (0.55 micromoles peptide; 0.138 μM estimated phloem concentration) or a 10×Bt.4Q7Flg22-High Rate (5.5 micromoles peptide; 1.38 μM estimated phloem concentration). In June 2018, the Bt.4Q7Flg22-injected trees were compared to untreated control trees within the same area of the grove using established methods for projecting citrus tree yield (“Forecasting Florida Citrus Production: Methodology & Development; 1971; by S. R. Williams for Florida Crop and Livestock Reporting Service). To quantify fruit set, three quaternary limbs at eye level were randomly chosen on each tree (n=8 trees per treatment ‘Valencia’ orange, n=10 trees per treatment ‘Ruby Red’ grapefruit). The circumference of each quaternary limb was measured at the junction where the limb began and used to calculate the cross-sectional area (CSA) of the limb using the following equations (where C=circumference, CSA=cross-sectional area, and r=radius):
Then, the total number of fruit on the quaternary limb distal to that junction were counted. To normalize for limb size, fruit set for each quaternary limb was quantified as the number of fruit on the limb divided by the CSA of the quaternary limb:
The fruit count per quaternary limb CSA is reported in
To further assess the size and volume of fruit setting per tree, the fruit diameter (mm) of at least 10 randomly chosen fruit per tree was measured using calipers placed at the widest point on each fruit. The average fruit diameter (mm) per tree for each treatment is reported in
The estimated volume of fruit normalized by limb CSA for each treatment is reported in
The measurements collected in June 2018 to assess fruit set in ‘Valencia’ orange and ‘Ruby Red’ grapefruit trees in Okeechobee, Fla. show increased fruit per limb and increased fruit size for trees of both varieties receiving trunk injections of 1× Low and 10× High rates of Bt.4Q7Flg22 (SEQ ID NO: 226) in April 2017, when comparing the mean and median values for all parameters measured versus the untreated control. The increased fruit set and size are predicative of increased yield. These results provide further evidence that trunk injection of citrus trees with Bt.4Q7Flg22 can be utilized to reduce C. liberibacter bacterial titers in orange (
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above polypeptides, recombinant organisms, methods, and seeds, without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.
Claims
1.-206. (canceled)
207. A method for treating a bacterial or fungal infection in a citrus plant, the method comprising injecting at least one antimicrobial peptide into the citrus plant.
208. The method of claim 207, wherein the injecting comprises injecting into a trunk or phloem of the plant.
209. The method of claim 208, wherein the injecting comprises injecting into the trunk of the plant.
210. The method of claim 207, wherein the bacterial infection comprises Huanglongbing (HLB), Asian Citrus Greening disease or Citrus Canker disease.
211. The method of claim 210, wherein the bacterial infection comprises Huanglongbing (HLB).
212. The method of claim 207, wherein the bacterial infection is caused by a bacterial species comprising any one of Candidatus liberibacter spp., Xanthomonas citri, and Xanthomonas axonopodis pv.
213. The method of claim 212, wherein the bacterial species comprises Candidatus liberibacter spp.
214. The method of claim 213, wherein the Candidatus liberibacter spp. comprises liberibacter asiaticus.
215. The method of claim 207, wherein the antimicrobial peptide is derived from a plant.
216. The method of claim 214, wherein the antimicrobial peptide is derived from a plant.
217. The method of claim 215, wherein the antimicrobial peptide is derived from a Citrus spp. plant.
218. The method of claim 216, wherein the antimicrobial peptide is derived from a Citrus spp. plant.
219. The method of claim 207, wherein the antimicrobial peptide comprises cysteine bonds.
220. The method of claim 215, wherein the antimicrobial peptide comprises cysteine bonds.
221. The method of claim 217, wherein the antimicrobial peptide comprises cysteine bonds.
222. The method of claim 207, wherein the antimicrobial peptide is produced in a bacterial expression system.
223. The method of claim 215, wherein the antimicrobial peptide is produced in a bacterial expression system.
224. The method of claim 217, wherein the antimicrobial peptide is produced in a bacterial expression system.
225. The method of claim 219, wherein the antimicrobial peptide is produced in a bacterial expression system.
226. The method of claim 207, wherein the antimicrobial peptide comprises a thionin or thionin-like polypeptide, a defensin, a flagellin or flagellin-associated polypeptide, or a harpin or harpin-like polypeptide.
227. The method of claim 226, wherein the antimicrobial peptide is a thionin, thionin-like polypeptide or defensin.
228. The method of claim 226, wherein the thionin, thionin-like polypeptide or defensin is injected in combination with a flagellin or flagellin-associated polypeptide, and/or a harpin or a harpin-like polypeptide.
229. The method of claim 227, wherein the thionin, thionin-like polypeptide or defensin comprises any one of SEQ ID NOs: 650-749.
230. The method of claim 229, wherein the thionin-like polypeptide comprises SEQ ID NO: 651.
231. The method of claim 207, wherein the antimicrobial peptide is fused to a phloem targeting sequence to form a fusion polypeptide.
232. The method of claim 231, wherein the phloem targeting sequence comprises any one of SEQ ID NOs: 641-649.
233. The method of claim 232, wherein the phloem targeting sequence comprises SEQ ID NO: 641.
234. The method of claim 227, wherein the thionin, thionin-like polypeptide or defensin is fused to a phloem targeting sequence to form a fusion polypeptide.
235. The method of claim 234, wherein the phloem targeting sequence comprises any one of SEQ ID Nos: 641-649.
236. The method of claim 235, wherein the phloem targeting sequence comprises SEQ ID NO: 641.
237. The method of claim 226, wherein the flagellin or flagellin-associated peptide comprises any one of SEQ ID NOs: 226, 1-225,227-375, 526, 528, 530, 532, 534, 536, 538, 540, 541, 751, 752, 754-766, 571-579, and 753.
238. The method of claim 237, wherein the flagellin or flagellin associated peptide comprises SEQ ID NO: 226, SEQ ID NO: 571 or SEQ ID NO: 752.
239. The method of claim 226, wherein the harpin or harpin-like polypeptide comprises any one of SEQ ID NOs: 587, 589, 591, 593, 594 and 595.
240. The method of claim 239, wherein the harpin or harpin-like polypeptide comprises SEQ ID NO: 587.
241. The method of claim 207, wherein treating the bacterial infection comprises a prophylactic treatment, treatment, prevention, and decreased disease progression on or in the plant or plant part.
242. The method of claim 207, wherein the citrus plant comprises Sweet orange (Citrus sinensis, Citrus maxima x Citrus reticulata), Bergamot Orange (Citrus bergamia, Citrus limetta x Citrus aurantium), Bitter Orange, Sour Orange or Seville Orange (Citrus aurantium, Citrus maxima x Citrus reticulata), Blood Orange (Citrus sinensis), Orangelo or Chironja (Citrus paradisi x Citrus sinensis), Mandarin Orange (Citrus reticulate), Trifoliate Orange (Citrus trifoliata), Tachibana Orange (Citrus tachibana), Clementine (Citrus clementina), Cherry Orange (Citrus kinokuni), Lemon (Citrus limon, Citrus maxima x Citrus medica), Indian Wild Orange (Citrus indica), Imperial Lemon (Citrus limon, Citrus medica x Citrus paradisi), Lime (Citrus latifoli, Citrus aurantifolia), Meyer Lemon (Citrus meyen); hybrids of Citrus x meyer with Citrus maxima, Citrus medica, Citrus paradisi and/or Citrus sinensis, Rough Lemon (Citrus jambhin), Volkamer Lemon (Citrus volkameriana), Ponderosa Lemon (Citrus limon x Citrus medica) Kaffir Lime (Citrus hystrix or Mauritius papeda), Sweet Lemon, Sweet Lime, or Mosambi (Citrus limetta), Persian Lime or Tahiti Lime (Citrus latifolia), Palestine Sweet Lime (Citrus limettioides), Winged Lime (Citrus longispina), Australian Finger Lime (Citrus australasica), Australian Round Lime (Citrus australis), Australian Desert or Outback Lime (Citrus glauca), Mount White Lime (Citrus garrawayae), Kakadu Lime or Humpty Doo Lime (Citrus gracilis), Russel River Lime (Citrus inodora), New Guinea Wild Lime (Citrus warburgiana), Brown River Finger Lime (Citrus wintersii), Mandarin Lime (Citrus limonia; (hybrids with Citrus reticulata x Citrus maxima x Citrus medica), Carabao Lime (Citrus pennivesiculata), Blood Lime (Citrus australasica x Citrus limonia) Limeberry (Triphasia brassii, Triphasia grandifolia, Triphasia trifolia), Grapefruit (Citrus paradisi; Citrus maxima x Citrus xsinensis), Tangarine (Citrus tangerina), Tangelo (Citrus tangelo; Citrus reticulata x Citrus maxima or Citrus paradisi), Minneola Tangelo (Citrus reticulata x Citrus paradisi), Orangelo (Citrus paradisi x Citrus sinensis), Tangor (Citrus nobilis; Citrus reticulata x Citrus sinensis), Pummelo or Pomelo (Citrus maxima), Citron (Citrus medica), Mountain Citron (Citrus halimii), Kumquat (Citrus japonica or Fortunella species), Kumquat hybrids (Calamondin, Fortunella japonica; Citranqequat, Citrus ichangensis; Limequat, Citrofortunella floridana; Orangequat, hybrid between Satsuma mandarin x Citrus japonica or Fortunella species; Procimequat, Fortunella hirdsiie; Sunquat, hybrid between Citrus meyeri and Citrus japonica or Fortunella species; Yuzuquat, hybrid between Citrus ichangensis and Fortunella margarita), Papedas (Citrus halimii, Citrus indica, Citrus macroptera, Citrus micrantha), Ichang Papeda (Citrus ichangensis), Celebes Papeda (Citrus celebica), Khasi Papeda (Citrus latipes), Melanesian Papeda (Citrus macroptera), Ichang Lemon (Citrus ichangensis x Citrus maxima), Yuzu (Citrus ichangensis x Citrus reticulata), Cam sành (Citrus reticulata x Citrus maxima), Kabosu (Citrus sphaerocarpa), Sudachi (Citrus sudachi), Alemow (Citrus macrophylla), Biasong (Citrus micrantha), Samuyao (Citrus micrantha), Kalpi (Citrus webber), Mikan (Citrus unshiu), Hyuganatsu (Citrus tamurana), Manyshanyegan (Citrus mangshanensis), Lush (Citrus crenatifolia), Amanatsu or Natsumikan (Citrus natsudaidai), Kinnow (Citrus nobilis x Citrus deliciosa), Kiyomi (Citrus sinensis x Citrus unshiu), Oroblanco (Citrus maxima x Citrus paradisi), Ugli (Citrus reticulata x Citrus maxima and/or Citrus x paradisi), Calamondin (Citrus reticulata x Citrus japonica), Chinotto (Citrus myrtifolia, Citrus aurantium or Citrus pumila), Cleopatra Mandarin (Citrus reshni), Daidai (Citrus aurantium or Citrus daidai), Laraha (Citrus aurantium), Satsuma (Citrus unshiu), Naartjie (Citrus reticulata x Citrus nobilis), Rangpur (Citrus limonia; or hybrid with Citrus sinensis x Citrus maxima x Citrus reticulata), Djeruk Limau (Citrus amblycarpa), lyokan, anadomikan (Citrus iyo), Odichukuthi (Citrus odichukuthi), Ougonkan (Citrus flaviculpus), Pompia (Citrus monstruosa), Taiwan Tangerine (Citrus depressa), Shonan gold (Citrus flaviculpus or Citrus unshiu), Sunki (Citrus sunki), Mangshanyen (Citrus mangshanensis, Citrus nobilis), Clymenia (Clymenia platypoda, Clymenia polyandra), Jabara (Citrus jabara), Mandora (Mandora cyprus), Melogold (Citrus grandis x Citrus paradisii/Citrus maxima/Citrus grandis), Shangjuan (Citrus ichangensis x Citrus maxima), Nanfengmiju (Citrus reticulata), or ShikwAsai (Citrus depressa).
243. The method of claim 232, wherein the citrus plant comprises Bergamot Orange (Citrus bergamia), Sour or Bitter Orange (Citrus aurantium), Sweet Orange (Citrus macrophylla), Key Lime (Citrus aurantiifolia), Grapefruit (Citrus paradisi), Citron (Citrus medica), Mandarin Orange (Citrus reticulate), Lemon (Citrus limon, or hybrids with Citrus medica x Citrus maxima, Citrus limonia, Citrus medica x Citrus maxima x Citrus medica), Sweet Lime (Citrus limetta), Kaffir Lime, (Citrus hystrix or Mauritius papeda), Lemon hybrid or Lumia (Citrus medica x Citrus limon), (Citrus medica x Citrus maxima x Citrus medica), Omani Lime (Citrus aurantiifolia, Citrus medica x Citrus micrantha), Jambola (Citrus grandis), Kakadu Lime or Humpty Doo Lime (Citrus gracilis), Pomelo (Citrus retkulata), Tangor (Citrus nobilis), or Sour Lime or Nimbuka (Citrus acida).
Type: Application
Filed: Dec 2, 2021
Publication Date: Mar 24, 2022
Inventors: Brian Thompson (Creve Coeur, MO), Michelle Leslie (Webster Groves, MO)
Application Number: 17/540,823
