Differential response of the two cotyledons of Vigna radiata in vitro.

Cotyledons of mature seeds of Vigna radiata were found to be variable in their response to N 6-benzytadenine, kinet in and zeatin. The two cotyledons of a seed were designated as CE and C; where CE referred to the cotyledon that remained closely attached to the embryonal axis, and the other more loosely attached cotyledon was referred to as C. Shoots formed from the proximal end of both explants in all nine cultivars studied. Shoot regeneration was faster and regeneration efficiency was higher in CE explants than in C explants in these cultivars. BA was found to be the most suitable cytokinin for both multiple shoot induction and regeneration.