Ontogeny of Somatic Embryos of Vigna aconitifolia, Vigna mungo and Vigna radiata

Abstract

Callus cultures were initiated from immature cotyledons of Vigna aconitifolia, V. mungo and V. radiata on MS medium supplemented with NAA, picloram or 2, 4-D. On transfer to L-6 liquid medium supplemented with low concentrations of picloram, GA₃ and cytokinins, large number of somatic embryos differentiated from the callus. The cells destined to become somatic embryos divided to form spherical or filamentous proembryos. From the filamentous proembryo, the embryo proper developed either at single or multiple sites. Development of somatic embryos from multiple sites resulted in several embryos connected by a common suspensor at the radicle end. Continued divisions of the proembryos led to globular, heart shaped and dicotyledonary stages of somatic embryogenesis. The somatic embryos of V. mungo and V. aconitifolia differentiated into tiny plantlets at low frequency (1%) in liquid suspension cultures supplemented with zeatin, picloram and GA₃.