US 7,521,237 B2
Methods for promoting maturation of conifer somatic embryos
Pramod K. Gupta, Federal Way, Wash. (US); Bonnie Larson, Granite Falls, Wash. (US); and Diane Holmstrom, Sumner, Wash. (US)
Assigned to Weyerhaeuser NR Company, Federal Way, Wash. (US)
Filed on Jun. 04, 2004, as Appl. No. 10/861,168.
Claims priority of provisional application 60/480942, filed on Jun. 23, 2003.
Prior Publication US 2005/0003415 A1, Jan. 06, 2005
Int. Cl. C12N 5/00 (2006.01)
U.S. Cl. 435—422 14 Claims
 
1. A method for producing mature pine somatic embryos, comprising the steps of:
(a) culturing pre-cotyledonary pine somatic embryos in, or on, a medium comprising maltose as the principal or sole source of metabolizable sugar and less than 0.5% of gellan gum to form cotyledonary pine somatic embryos; and
(b) culturing the cotyledonary pine somatic embryos from step (a) in, or on, a maturation medium comprising between about 1% to about 6% sucrose to produce mature pine somatic embryos.