Somatic embryogenesis in angiosperm cell tissue and organ cultures

Abstract

A survey of literature shows that somatic embryogenesissensu stricto has been achieved in only 102 species, subsequent plantlet formation in 51 of these species and eventual propagation in still fewer of them. The contrast between zygotic and somatic embryogenesis is rather marked. The potential for somatic embryogenesis is genotype-specific. Ultrastructural, histological and biochemical studies are limited. Published evidence shows that auxins affect both transcriptional and translational events involved in the induction of somatic embryogenesis; nonetheless, the primary action of auxin is not known. Growth inhibitors occurring in developing seeds play a significant role in somatic embryogenesis. Employing histologically simpler tissue systems such as nucellus and endosperm as primary explants is advocated. Some limitations in the existing studies and certain prospects are identified.