Protoplasts isolated enzymatically from cotyledons of immature pods can be rapidly obtained in great numbers. Protoplast regenerating a wall and sustaining division can be induced to form a callus. Protoplast division occurred after 2-3 days of culture and compact clusters of cells appeared in the second week of the culture. Transfers of these clusters to the liquid medium resulted in the formation of rapidly growing callus tissues, which turned green after exposure to light.