EMBRYOGENIC ABILITY IN LONG-TERM CALLUS-CULTURES OF RICE (ORYZA-SATIVA L)

Embryogenic cultures with potential for green plant regeneration in lo ng term cultures were established in indica rice cultivars. White, com pact, embryogenic callus cultures with high plant regenerability were derived from mature seed embryos. Selective subculturing of yellowish white and compact regions (embryogenic clusters) of the primary callus onto MS medium with 2.32 mu M kinetin, 3.78 mu M ABA, 1 g/l caesin hy drolysate and 164.8 mM mannitol produced somatic embryos. Cultures mai ntained on this medium exhibted capacity for plant regeneration even a fter 24 months of culture. Green plants obtained from somatic embryos were grown to maturity.