Patent ID: 8313946

Claim:
A method for developing plant embryos from proliferative plant cells, comprising (A) culturing proliferative plant cells for a first period of time in a liquid embryonic development medium that comprises (i) one or more phytohormones, (ii) a source of reduced nitrogen, and (iii) carbohydrate, wherein the liquid embryonic medium either (a) does not contain a non-permeating osmotic agent, or (b) comprises a low percentage concentration of a non-permeating osmotic agent selected from the group consisting of 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, and 3.5%; (B) separating the liquid embryonic medium from the embryos after expiration of the first period of time; and (C) conditioning the embryos by storing them in a high relative humidity environment for a second period of time prior to germination; wherein the conditioned embryos are plant embryos developed from proliferative plant cells.