Sweetpotato plant named ‘NCPUR13-0315’

Abstract

Ipomoea batatas ‘NCPUR13-0315’ is a purple fleshed, smooth skinned, dark purple-colored, table stock sweetpotato. ‘NCPUR13-0315’ has good yields of well-shaped and uniformly sized No.1 sized roots. It is a mid-season cultivar for optimal production of No.1 sized roots.

Description

Latin name of the genus and species: The Latin name of the novel plant cultivar disclosed herein is Ipomoea batatas (L.) Lam.

Variety denomination: This new and distinct sweetpotato cultivar of Ipomoea batatas (L.) Lam. has been given the denomination ‘NCPUR13-0315’.

BACKGROUND OF THE INVENTION

Ipomoea batatas is a member of the morning glory family Convolvulaceae. This species is grown worldwide, and it exhibits a wide range of plant forms and colors. Grown by farmers worldwide, the cultivated members of Ipomoea batatas are commonly produced for consumption of their nutritious, enlarged storage roots. This contrasts with potatoes (Solanum tuberosum) that produce an edible tuber derived from an underground stem, which is similar in structure to above ground stems.

Purple fleshed sweetpotatoes are a small percentage of the US market with there being two distinct types. The first type is white skinned and purple fleshed with the main cultivar in this group being the heirloom cultivar ‘Okinawa’ (not patented), which is grown in Hawaii for the U.S. market. This heirloom cultivar is very poorly adapted to the growing regions on the mainland including NC, CA, LA and MS. The second type is purple skinned and purple fleshed. There are a few cultivars of this second type grown in the U.S., mainly ‘Mokuau’ aka ‘Molokai Purple’ (not patented), which is grown in Hawaii, and ‘Stokes Purple’ (U.S. Plant Pat. No. 17,976), which is grown on the U.S. mainland. Several different names have been used for these and other similar varieties, some of which have been previously introduced from Southeast Asia via various methods. However, none of these are particularly well adapted to NC growing conditions. ‘NCPUR06-0020’ (U.S. Plant Pat. No. 25,538) was developed and released for its high pigment value for industrial use, but its eating quality is poor.

‘NCPUR13-0315’ provides an improvement over ‘Stokes Purple’ and other purple-skinned, purple-fleshed cultivars known to the inventors for table stock use in terms of its adaptability, yield, and marketable shapes.

Lineage. ‘NCPUR13-0315’ originated from a paired cross between ‘NCP06-0016’, the female parent, and ‘NC08-0553’, the male parent, in Raleigh, N.C. Both parents are non-patented lines from the breeding program. Plants were crossed from October 2011 to April 2012 with seed from the same cross combined across the crossing dates.

Seedlings from the 2012 purple polycross nursery were planted in greenhouses in Clinton, N.C. in March of 2013. A single cutting was taken from each seedling and planted in the field on May 23, 2013 in Kinston N.C. and ‘NCPUR13-0315’ was selected as a “single plant selection” on Aug. 27, 2013. This “single plant selection” included all of the storage roots derived from the single plant cutting planted on May 23^rd, with 2-10 storage roots being saved over the winter in our storage facility in Clinton, N.C. for propagation the next year via vegetive propagation in the same location.

Asexual Reproduction. The first asexual reproduction of ‘NCPUR13-0315’ occurred in Clinton, N.C. ‘NCPUR13-0315’ has been propagated as vegetative stem cuttings and/or storage root derived stem cuttings derived from adventitious sprouts emanating from its storage roots since its original selection in August of 2013 in Kinston, N.C. After further cycles of selection for horticultural traits and disease screenings, ‘NCPUR13-0315’ was subjected to meristem tip culture and subsequent tissue culture maintenance to eliminate viruses and pathogens via meristem tip culture. The characteristics disclosed herein for ‘NCPUR13-0315’ have remained stable and the plant has reproduced true to type through successive generations of asexual propagation.

SUMMARY OF THE INVENTION

‘NCPUR13-0315’ is a purple-fleshed, dark purple skin colored table stock sweetpotato. The storage roots of ‘NCPUR13-0315’ tend to be blocky to round elliptic; longer than ‘Covington’ (U.S. Plant Pat. No. 18,516) and shorter than ‘Stokes Purple’, and more uniform in size and shape than ‘Stokes Purple’. Marketable yields of ‘NCPUR13-0315’ are similar to ‘Covington’ and higher than ‘Stokes Purple’, the main orange and purple fleshed sweetpotato cultivars produced in the US, respectively. Plants from sprouted roots are ready about a week before ‘Covington’, and a week or two later than ‘Stokes Purple’. The anthocyanin content averages about twice as much as ‘Stokes Purple’. The flavor of baked storage roots of ‘NCPUR13-0315’ have been judged to be good by standardized and informal taste panels, similar to ‘Stokes Purple’, the main cultivar of this type.

BRIEF DESCRIPTION OF THE DRAWINGS

The photographs in the drawings were made using conventional techniques and show the colors as true as reasonably possible by conventional photography. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description, which accurately describe the colors of the new Ipomoea batatas.

FIG. 1 is a color photograph of the above ground plant canopy produced by the new cultivar ‘NCPUR13-0315’ (abbreviated as NCP13-0315) (left panel), ‘Stokes Purple’ (‘NC413’) (middle panel) and ‘NCPUR06-0020’ (abbreviated as NCP06-0020) (right panel) 57 days after planting at in Kinston, N.C. in 2017.

FIGS. 2A-2C are color photographs of typical mature leaves of ‘NCPUR13-0315’ (abbreviated as ‘NCP13-0315’) (FIG. 2A), ‘Stokes Purple’ (‘NC413’) (FIG. 2B), and ‘NCPUR06-0020’ (abbreviated as ‘NCP06-0020’) (FIG. 2C), 57 days after planting in Kinston, N.C. in 2017.

FIGS. 3A-3C are color photographs showing typical vines and the variety of leaves of ‘NCPUR13-0315’ (abbreviated as ‘NCP13-0315’) (FIG. 3A), ‘Stokes Purple’ (‘NC413’) (FIG. 3B) and ‘NCPUR06-0020’ (abbreviated as ‘NCP06-0020’) (FIG. 3C), 57 days after planting in Kinston N.C. in 2017.

FIGS. 4A-4C are color photographs showing typical storage roots produced by ‘NCPUR13-0315’ (FIG. 4A), ‘Stokes Purple’ (‘NC413’) (FIG. 4B) and ‘NCPUR06-0020’ (FIG. 4C). The photographs were taken of storage roots that had been stored in a sweetpotato storage facility for approximately three months after harvest.

DETAILED BOTANICAL DESCRIPTION

The following is a detailed description of the botanical characteristics of a new and distinct cultivar of Ipomoea batatas plant given the designation ‘NCPUR13-0315’. All colors cited herein refer to The Royal Horticulture Society Colour Chart designations (The Royal Horticultural Society, London, 1995, 4^th ed.) except where general terms of ordinary dictionary significance are used. Plant descriptions are based on the standardized international sweetpotato descriptors established jointly by the International Potato Center (CIP), Lima, Peru; The Asian Vegetable Research and Development Center (AVRDC), Taipei, Taiwan; and the International Board for Plant Genetics Resources (IBPGR), Rome, Italy (CIP, AVRDC, IBPGR. 1991. Descriptors for Sweet Potato. Huaman, Z., editor. International Board for Plant Genetic Resources, Rome, Italy, 134pp.). Where dimensions, sizes, colors, and other characteristics are given, it is to be understood that such characteristics are approximations or averages set forth as accurately as practicable.

The descriptions and measurements of plant canopy reported herein were done on field grown plants 57 days after planting (DAP). The plants were grown in Kinston, N.C. under common commercial sweetpotato production practices during June through October. ‘NCPUR13-0315’ has not been observed under all possible environmental conditions; therefore, the phenotype may vary under different environmental conditions such as season, temperature, light intensity, day length, cultural conditions, and the like, without however, any variance in the genotype.

The following discussion provides a description of the new Ipomoea batatas ‘NCPUR13-0315’ with ‘Stokes Purple’ and ‘NCPUR06-0020’ for comparison. The parent lines ‘NC06-0016’ and ‘NC08-0553’ were no longer propagated at the time when ‘NCPUR13-0315’ was being evaluated, so they were not used for comparison. Neither of the parent lines are grown commercially.

• Classification.
  • • Botanical name.—Ipomoea batatas (L.) Lam.
    • Common name.—Sweetpotato.
    • Variety name.—‘NCPUR13-0315’.
• Growth conditions whole-plant canopy structure: FIG. 1 is a color photograph of the canopy biomass produced by the new cultivar ‘NCPUR13-0315’ and contrasted with ‘Stokes Purple’, and ‘NCPUR06-0020’. Measurements were collected on field-grown plants at 57 DAP using 20 measurements per trait and recorded as the mean±standard deviation. Measurements of key features are presented in Table 1.
• Foliage: The leaves of ‘NCPUR13-0315’ are alternate and simple in structure, and cordate to lobed in shape with 1-3 teeth to slight lobing and 0-3 lobes. (see FIGS. 2A and 3A). The leaves have a smooth texture and matte finish. The shape of the central lobe is triangular. Stem tip anthocyanin coloration is absent and stem tip pubescence is absent. A detailed description of leaf traits is provided in Table 1. A typical inflorescence of ‘NCPUR13-0315’ has one cluster of 7.6±1.8 flowers per peduncle. Peduncles are green (144A), averaging 16.5±3.3 cm long and about 2.9±0.3 mm in diameter. Flowers are 4.6±0.5 cm long from the base of the calyx, and the corolla 4.0±0.2 cm wide. Petals are fused to form a rounded limb with smooth edges. The inner throat color is purple (N81A) with a light purple (76C) inner and outer limb. Upper and lower flower texture is smooth. The five sepals making up the calyx are ovate with an acuminate tip. The three inner sepals are 11±0.0 mm long and 6.2±0.6 mm wide while the outer two sepals are shorter, 8.0±0.0 mm long and 2.6±0.2 mm wide. All sepals are green (144A) with smooth edges. The stigmata average 14.4±1 mm in length and are white and the stigma is inserted. Anthers are white with the style white with purple at the base (76C). No fragrance is present.

TABLE 1
Descriptive traits for ‘NCPUR13-0030’, ‘Stokes Purple’ and ‘NCPUR06-
0020’ measured on field plants 57 days after planting in Kinston NC
in 2017. Numerical measurements are averages of 20 values with
standard deviation.
			‘Stokes
		‘NCPUR13-	Purple’	‘NCPUR06-
Clone	Units	0315’	(‘NC413’)	0020’
#Main vines		1.7 ± 0.6	1.4 ± 0.5	1.6 ± 0.5
Main vine length	cm	125 ± 27	150 ± 27	95 ± 29
Main vine diameter	mm	7.3 ± 1.3	7.1 ± 1.8	7.0 ± 2.1
at base
Main vine diameter	mm	6.1 ± 0.6	4.7 ± 0.7	5.0 ± 0.8
at 50 cm from base
Number of lateral		5.9 ± 1.8	5.5 ± 2.2	5.5 ± 1.8
branches on main
vine
Predominant vine		green 144B	green 144B	green 144A
color		to 144C		to 144B
Secondary vine		purple nodes	green with	none
color		N79A	few purple
			spots N79A
First fully expanded	cm	4.1 ± 0.9	5.0 ± 0.8	4.0 ± 1.2
internode length
Mature leaf color;		green, 147A	green, 147A	green,
upper surface				between
				147A and
				147B
Mature leaf color;		green, 146B	green, 147B	green,
lower surface				between
				147B and
				147C
Mature leaf venation		green, 146B	green, 146B to	purple spot
		to 146C	C	in the base
				of the main
				rib, N79B
Young leaf color:		green, 146A	green (146B	green, 146B
upper surface		to 146B	to146C) with
			slight purple
			(N79A)
			margins
Young leaf color:		green, 146B	green (146B	green, 146D
lower surface		to 146C	to 146C) with
			slight purple
			(N79A)
			margins
Mature Leaf length	cm	10.8 ± 1.1	11.0 ± 0.9	11.9 ± 1.2
Mature leaf width	cm	13.8 ± 1.4	13.5 ± 1.7	11.1 ± 0.8
Mature leaf shape;		lobed	lobed	triangular to
general outline				slightly
				lobed
Mature leaf shape;		slight to	very slight to	very slight to
lobing		moderate	slight	moderate
Mature leaf shape;		0-5	0-3	0-3
number of lobes
Petiole color:		green with	green 144B to	green 144B
primary		purple near	144C
		stem 144A
		and 144B
Petiole color:		N79A	none	none
seconday
Petiole length	cm	17 ± 2.7	17.1 ± 1.7	21.4 ± 2.4
Petiole diameter	mm	5.9 ± 1.1	5.2 ± 0.7	5.2 ± 0.7
Storage root skin		purple,	purple, N79B	purple, N77A
color		N186C to	to N79C	to N79B
		N77A
Storage root flesh		61A to 71A	purple, 71A	N79B
color

• Storage roots: ‘NCPUR13-0315’ produces purple-fleshed (61A to 71A), smooth skinned, storage roots that are generally blocky to round elliptic. The skin color of ‘NCPUR13-0315’ is dark purple (N186C to N77A) (FIG. 4A). One of the more desirable attributes of ‘NCPUR13-0315’ is that it produces uniformly shaped roots with a high percentage of number 1 grade sized roots. Length to diameter ratios of storage roots in 9 trials over four years averaged 2.5, 3.2 and 2.3 for ‘NCPUR13-0315’, ‘Stokes Purple’ and ‘NCPUR06-0020’, respectively. Root number was measured for seven trials in 2017-2019 with ‘NCPUR13-0315’ averaging 4.4 roots per plant, while ‘Stokes Purple’ and ‘NCPUR06-0020’ averaged 2.6 and 4.7 roots per plant, respectively. Carbohydrate profiles, anthocyanin and asparagine levels are presented in Table 2. All three of these cultivars have moderate starch levels, with anthocyanin levels being greater in ‘NCPUR06-0020’. The flavor of the baked storage roots of ‘NCPUR13-0315’ have been judged to be good by standardized and informal taste panels comparing similarly with ‘Stokes Purple’.

TABLE 2
Select chemistry of storage roots of ‘NCPUR13-0315’,
‘NCPUR06-0020’ and ‘Stokes Purple’ from trials from 2014 to 2018,
samples measured 6-10 weeks after harvest.
			Fructose	Glucose	Sucrose
			g/100 g	g/100 g	g/100 g
Clone	n	% DM	fresh wt	fresh wt	fresh wt
‘NCPUR13-	22	24.1 ± 2.0	0.64 ± .10	0.88 ± .15	1.31 ± .44
0315’
‘NCPUR06-	51	27.8 ± 1.8	0.34 ± .06	0.44 ± .08	0.87 ± .20
0020’
‘Stokes	39	28.2 ± 1.7	0.31 ± .04	0.36 ± .06	1.07 ± .21
Purple’
			Starch	Asparagine	TMA
			g/100 g	mg/g fresh	mg/g
	Clone	n	fresh wt	wt	dry wt
	‘NCPUR13-	22	46.1 ± 3.8	0.86 ± .50	3.02 ± .73
	0315’
	‘NCPUR06-	51	51.9 ± 5.6	0.73 ± .37	3.55 ± .94
	0020’
	‘Stokes	39	57.3 ± 4.1	0.913 ± .50	1.42 ± .68
	Purple’
Values are based on predictions using Near Infrared Reflectance Spectroscopy (NIRS) calibrations.
Means ± std dev.
TMA total monomeric anthocyanins

• Storage root yield: Yield comparisons of ‘NCPUR13-0315’ are with ‘Stokes Purple’ (‘NC413’) the most common purple grown in NC and ‘Covington’, the major orange fleshed sweetpotato cultivar grown in North Carolina (Table 3). ‘NCPUR06-0020’ is not used in trials for table stock use and was not in these trials. In the 9 replicated yield trials, ‘NCPUR13-0315’ averaged 189% of the total marketable yield (TMY) of ‘Stokes Purple’ and 114% the TMY of ‘Covington’. ‘NCPUR13-0315’ had a higher percentage of No.1 roots, the most valuable class, and fewer jumbos and culls (62% No.1, 21% canner, 11% jumbo, and 6% culls) compared to ‘Stokes Purple’ (51% No.1, 16% canner, 19% jumbo and 14% culls). Thus, for ‘NCPUR13-0315’, the value per ton harvested is higher, in addition to the higher tonnage per acre, as compared to ‘Stokes Purple’.

TABLE 3
‘NCP13-0315’ average yield and standard deviation and
comparison to ‘NC413’ (‘Stokes Purple’) and ‘Covington’ in
9 replicated yield trials in 2016-2019.
		Market-	% Marketable yield
	Total	able	%	% ‘Coving-
Trial	yield bu/A	yield bu/A	‘NC413’	ton’
2016 Clinton Purple TS	1080 ± 106	998 ± 68	181 ± 64	130 ± 27
2016 Kinston Purple TS	858 ± 41	843 ± 41	221 ± 75	114 ± 8
2017 Clinton Purple TS	523 ± 49	513 ± 58	136 ± 21
2017 Kinston Purple TS	535 ± 105	519 ± 109	152 ± 46	124 ± 34
2017 Scott Purple TS	472 ± 120	446 ± 106	168 ± 110	110 ± 13
2018 Kinston Purple TS	416 ± 44	416 ± 44	205 ± 38	156 ± 24
2019 Kinston NCG	515 ± 147	478 ± 128	NA	91 ± 25
2019 Kinston Purple TS	356 ± 104	317 ± 95	318 ± 110	109 ± 40
2019 Clinton Purple TS	503 ± 74	474 ± 73	129 ± 46	83 ± 14
Average	584	556	189	114
		%	%	%	%
	Trial	No. 1's	Canner's	Jumbo's	Culls
	2016 Clinton Purple TS	61 ± 7	18 ± 5	14 ± 5	7 ± 5
	2016 Kinston Purple TS	65 ± 5	24 ± 6	10 ± 4	2 ± 0
	2017 Clinton Purple TS	67 ± 5	13 ± 2	17 ± 8	2 ± 2
	2017 Kinston Purple TS	76 ± 6	13 ± 5	8 ± 6	3 ± 4
	2017 Scott Purple TS	62 ± 14	14 ± 9	19 ± 19	5 ± 4
	2018 Kinston Purple TS	74 ± 13	20 ± 11	6 ± 8	0
	2019 Kinston NCG	51 ± 6	30 ± 7	9 ± 5	10 ± 5
	2019 Kinston Purple TS	44 ± 8	30 ± 5	12 ± 6	14 ± 5
	2019 Clinton Purple TS	57 ± 7	28 ± 7	8 ± 4	7 ± 1
	Average	62	21	11	6
*50 lb bushels per acre
Size grading uses the definitions of the National Sweetpotato Collaborators Group:
US # l's - Roots 2″ to 3½″ diameter, length of 3″ to 9″ , must be well shaped and free of defects.
Canners - Roots 1″ to 2″ diameter. 2″ in length.
Jumbo's - Roots that exceed the diameter, length and weight requirements of the above 2 grades, but are of marketable quality
Total Marketable Yield - Sum of US #1. Canners and Jumbo's.
Culls - Roots >1″ in diameter and so misshapen or unattractive that they could not fit as marketable roots in any of the above
Percent US #1's - Calculated by dividing the weight of US #1's by the Total Marketable Yield weight.

• Disease or pest resistance: The results of disease evaluations for ‘NCPUR13-0315’ are summarized in Table 4. Based on multiyear disease evaluations, ‘NCPUR13-0315’ is moderately resistant to Fusarium wilt (Fusarium oxysporum Schlect. f. sp. batatas (Wollenw.) Snyd. & Hans.), susceptible to Streptomyces soil rot (Streptomyces ipomoeae (Person & W. J. Martin) Waksman & Henrici) and to southern root knot nematode, Meloidogyne incognita (Kofoid & White).

TABLE 4
Disease screen results for ‘NCPUR13-0315’ by year over four years for
Southern root-knot nematode (Meloidogyne incognita) (Kofoid & White)
(SRKN), fusarium wilt (Fusarium oxysporum Schlect. f sp.batatas
(Wollenw.) Snyd. & Hans.) (FW), and Streptomyces soil rot
(Streptomyces ipomoeae (Person & W. J. Martin) Waksman & Henrici)
(Field SSR).
Year	SRKN	FW	Field SSR
2019	—	R	—
2018	MS	R	—
2017	S	MR	S
2016	—	MS	—
Long term average resistance ratings for select check clones
‘NCPUR06-0020’	MS	MR	S
‘Stokes Purple’	R	MR	S
‘Covington’	R	R	R
Scale - HS — highly susceptible, S — susceptible, MS — moderately susceptible, MR — moderately resistant, R resistant, HR — highly resistant.
The root knot nematode rating is based on the number of galls on roots counted eight weeks after inoculation with 10,000 eggs of M. incognita race 3 in plants established in four-inch pots. Gall count classes: HR = 0; R = 1-3; MR = 4-10; MS = 11-30; S = 31-100; HS = 101 + galls. 4 reps.
The Fusarium wilt rating involves dipping fresh cut plants in a solution of Fusarium oxysporum spores then rating for mortality and vascular tissue browning. 3 reps of five plants each are used.
Streptomyces soil rot is screened in a field trial with high levels of SSR pressure. Plots are rated for fibrous root damage, yield and storage root lesions.

• Long term storage: Sweetpotatoes from yield trials are stored and rated for the ability to last until the next crop season. They are rated on a visual pithiness scale from 0 to 4, where 0 has visible holes, to 4, where there is no visible pithiness, or they look like freshly harvested roots. This rating system is used as an estimate of how well the roots have lasted in storage. The sweetpotatoes are also rated for sprouting, another measure of long-term storage, which is also reflected in the pithiness score. ‘NCPUR13-0315’ had an average score of 1.8 on the pithiness scale over 5 trials from 2014 to 2019 (Table 5). In the same years, ‘Covington’ averaged 2.4, ‘Stokes Purple’ averaged 2.4, and ‘NCPUR06-0020’ averaged 2.8 on the pithiness scale, which are all considered good for storage ability. Thus, the storage ability of ‘NCPUR13-0315’ can be considered to be fair. Sprouting in storage was minimal for ‘NCPUR13-0315’.

TABLE 5
Pithiness rating as an estimate of long-term storage of
‘NCPUR13-0315’ compared to check lines 2014-2019.
	Clone	Pithiness	# Ratings
	‘NCPUR13-0315’	1.8 ± .8	5
	‘NCPUR06-0020’	2.8 ± 0.6	36
	‘Covington’	2.4 ± 0.4	185
	‘Stokes Purple’	2.4 ± 0.6	31
Pithiness rating: six storage roots cut and rated in August of the year after harvest. Mean ± std dev Scale: 0 = large holes; 1 = holes, light areas; 2 = no holes, some light areas; 3 = slightly pithy; 4 = no pithiness.

• Flood tolerance: The flood tolerance of ‘NCPUR13-0315’, observed under wet conditions, appears to be significantly less than ‘Covington’. ‘Covington’ is considered tolerant to wet conditions, though any cultivar will be lost if submerged. ‘NCPUR13-0315’ will show a proliferation of lenticels under wet conditions.

Claims

1. A new and distinct cultivar of Ipomoea batatas plant named ‘NCPUR13-0315’, substantially as illustrated and described herein.