A METHOD FOR LONG-TERM MICROPROPAGATION OF PHASEOLUS-COCCINEUS L

A method for long-term plant regeneration of Phaseolus coccineus L, is described. Shoot-tips and cotyledonary nodes cultured on a Murashigc and Skoog medium supplemented with N6-benzylaminopurine, 10 muM, and a lpha-naphthaleneacetic acid, 1 muM, formed multiple bud-shoots. These shoots were transferred to medium containing BAP 1 muM, NAA 0.1 muM, a nd gibberellic acid 3 muM to promote shoot growth and further shoot mu ltiplication. Rooting was achieved in medium with 11 muM indole-3-acet ic acid. Rooted plants grew to maturity and were fertile. Cultures hav e maintained their ability to regenerate plants for more than two year s. A sample of 30 regenerated plants (R0) was tested for chromosome nu mber, all of them being diploid; seven isozymatic systems were electro phoretically analyzed in 82 R0 regenerated plants. No differences were observed in their electrophoretic patterns in comparison with those s hown by seedlings. Histological studies revealed the origin of buds fr om calluses via organogenesis.