DEVELOPMENT OF SOMATIC EMBRYOS IN NORWAY SPRUCE

Embryogenic cell lines of Norway spruce consist of a large number of s omatic embryos. The cell lines have been divided into two groups, A an d B. The group B embryos are developmentally blocked, Extracts of matu re spruce seeds stimulate group B embryos to develop a morphology comp arable to group A embryos. However, seed extract inhibits early embryo development. The active components in seed extract were shown probabl y to be proteins. Extracts of mature seeds contain chitinase-like prot eins as recognized by an antibody towards chitinase 4 in sugar beet. P roteins of similar sizes were detected by the same antibody in the con ditioned medium of group A, but not in group B. A chitinase cl-related chitinase and a nod factor had a stimulating effect on early embryo d evelopment, but did not influence the later stages of embryo developme nt.