Method of ex vitro sowing, germination, growth and conversion of plant somatic embryos or germinants

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. The particles of the solid component are adapted to remain in contact with the embryo or germinant after of the flowable or semisolid material dissipates, thereby providing continuing physical support for the embryo or germinant after the dissipation. The invention also relates to seedlings produced in this way and to the nutrient solution.