Abstract: A method for promoting maturation and development of vigorous conifer (gymnosperm) somatic embryos comprising the use of S(+)-ABA as the substantive form of ABA.

Abstract: A method for promoting maturation and development of vigorous conifer (gymnosperm) somatic embryos comprising the use of S(+)-ABA as the substantive form of ABA.

Abstract: A method for promoting maturation and development of vigorous conifer (gymnosperm) somatic embryos comprising the use of S(+)-ABA as the substantive form of ABA.

Abstract: A method for reproducing conifers by somatic embryogenesis is disclosed. A galactose-containing compound is used as a carbon source for an embryogenic culture during at least one of the steps of induction, proliferation, and prematuration.

Abstract: The invention provides a nutrient medium useful for sowing a somatic plant embryo or germinant of conifer species, which comprises particles of a solid component present within a flowable or semi-solid component containing water and a carbohydrate nutrient for the embryos or germinants. The nutrient medium has a fluidity such that at least some of the flowable or semi-solid component containing the carbohydrate nutrient remains in contact with the embryos or germinant at least until the embryo or germinant establishes vigorous growth under environmental conditions effective for such growth. The particles of the solid component are adapted to remain in contact with the embryo or germinant after of the flowable or semi-solid material dissipates, thereby providing continuing physical support for the embryo or germinant after the dissipation.

Abstract: A method of sowing a somatic plant embryo or germinant of a conifer species to facilitate subsequent development of the embryo or germinant into an autotrophic seedling. The method involves the following steps carried out ex vitro in non-sterile conditions: providing a nutrient medium comprising particles of a solid component present within a flowable or semi-solid component containing water and a carbohydrate nutrient for the embryo or germinant, dispensing a quantity of the nutrient medium onto a surface of a porous solid growth substrate for the somatic plant embryo or germinant, to and contacting the plant embryo or germinant with the nutrient medium. The nutrient medium has a fluidity such that at least some of the flowable or semi-solid component containing the carbohydrate nutrient remains in contact with the embryo or germinant at least until the embryo or germinant establishes vigorous growth under environmental conditions effective for such growth.

Abstract: A method of sowing a somatic plant embryo or germinant of a conifer species to facilitate subsequent development of the embryo or germinant into an autotrophic seedling. The method involves the following steps carried out ex vitro in non-sterile conditions: providing a nutrient medium comprising particles of a solid component present within a flowable or semi-solid component containing water and a carbohydrate nutrient for the embryo or germinant, dispensing a quantity of the nutrient medium onto a surface of a porous solid growth substrate for the somatic plant embryo or germinant, and contacting the plant embryo or germinant with the nutrient medium. The nutrient medium has a fluidity such that at least some of the flowable or semi-solid component containing the carbohydrate nutrient remains in contact with the embryo or germinant at least until the embryo or germinant establishes vigorous growth under environmental conditions effective for such growth.

Abstract: A method for reproducing conifers by somatic embryogenesis is disclosed. A galactose-containing compound is used as a carbon source for an embryogenic culture during at least one of the steps of induction, proliferation, and prematuration.

Abstract: The invention comprises methods for producing mature desiccated and desiccation-tolerant somatic embryos, particularly conifer embryos. The methods include the application of a growth-promoting hormone such as abscisic acid (ABA) to the immature embryos during development. The embryos are also water stressed during development. The concentration of the ABA undergoes a net increase relative to its initial concentration to reach a peak prior to discontinuing ABA treatment when the embryos have attained a moisture content of between 32 and 55%. The water stressing may remain constant or may undergo a net increase in intensity over the period of time during which it is applied to the embryos. The method may optionally include the further water stressing of the mature embryos to further reduce moisture contents of the embryos preferably to the level at which the embryos are tolerant of freezer storage.

Abstract: A desiccation-tolerant mature viable gymnosperm somatic embryo is characterized by a moisture content of less than about 55%. Preferably the moisture content is less than about 45%, and for optimal storage capability at freezing temperatures, less than about 36%. The embryo may have a dry weight and per embryo lipid content higher than the lipid content and dry weight of the corresponding gymnosperm zygotic embryo. Preferred desiccation-tolerant gymnosperm somatic embryos are coniferous somatic embryos having a moisture content of less than about 55%.

Abstract: Desiccated mature gymnosperm somatic embryos, preferably coniferous somatic embryos having a moisture content of less than about 55%, are prepared by water stressing immature embryos in a medium comprising a metabolizable carbon source and a suitable growth regulator influencing embryo development, for a period of time and under conditions sufficient to yield mature viable somatic embryos having a moisture content in the specified range. The water stressing should may be environmental, as by controlled declining relative humidity. Or a suitable osmotic or non-osmotic water stress agent can be used. The use of a non-permeating osmotic water stress agent such as polyethylene glycol of molecular weight at least about 1,000 is preferred, in which case the water stress should simulate a non-osmotic water stress. An example of a suitable preferred growth regulator is abscisic acid.

Abstract: A desiccated mature gymnosperm somatic embryo characterized by having a moisture content which is lower than the moisture content of its corresponding zygotic embryo and a dry weight and per embryo lipid content which are higher than the lipid content and dry weight of its corresponding gymnosperm zygotic embryo. Preferred desiccated gymnosperm somatic embryos are conifer somatic embryos having a moisture content ranging between 10 and 55%. Also within the scope of the invention is a method for producing desiccated somatic embryos. The method comprises developing immature embryos in a medium comprising at least one non-permeating water stress agent, a metabolizable carbon source and a growth regulator having an influence on embryo development for a period of time sufficient to yield the recovery of mature somatic embryos having a moisture content which is lower than the moisture content of corresponding zygotic embryos.

Abstract: Conifer somatic embryos can be desiccated to a moisture content below 50%. A moisture content as low as 10% can be produced. The desiccated somatic conifer embryos have greatly increased ability to store lipids and other nutrients as compared to the corresponding zygotic embryo. The embryos are desiccated using a method which requires the utilization of ABA and PEG.