PLANT-REGENERATION FROM PROTOPLASTS OF ADZUKI BEAN (VIGNA-ANGULARIS OHWI AND OHASHI)

Protoplasts were isolated from suspension cultures of adzuki bean (Vig na angularis OHWI & OHASHI). The isolated protoplasts were cultured on MURASHIGE and SKOOG (MS) medium containing 2,4-dichrolophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). First cell division occurr ed within 3 days. Plating efficiency of the protoplasts was about 30% after 10 days. Frequency of protoplast division on agarose-solidified medium was higher than that on liquid medium. When the concentrations of 2,4-D and BAP were 1 mg per liter each in the medium, the division frequency was highest among the six combinations of plant growth regul ators tested. A significant difference in the frequencies of protoplas t division was observed among the 5 cultivars. Colonies 0.5 mm to 1 mm in diameter were transferred to solid MS medium containing 0.5 mg/l 2 ,4-D and 1.0 mg/l BAP. Two weeks after the transfer, the diameter of t he colonies had become twice as large. Calli up to 2 mm in diameter we re transferred onto solid MS medium supplemented with BAP, kinetin, tr ans-zeatin and 3-indoleacetic acid (IAA) (regeneration medium). Shoots and the related organogenic tissues were observed in the calli which had been transferred to the regeneration medium. The shoots were trans ferred onto MS medium without plant growth regulators and they develop ed into whole plants in pots and produced normal seeds.