Embryogenic ability in long term callus cultures of rice (Oryza sativa L.)

Embryogenic cultures with potential for green plant regeneration in long term cultures were established in indica rice cultivars. White, compact, 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 2.32μM kinetin, 3.78μM ABA, 1 g/1 caesin hydrolysate and 164.8 mM mannitol produced somatic embryos. Cultures maintained on this medium exhibted capacity for plant regeneration even after 24 months of culture. Green plants obtained from somatic embryos were grown to maturity.