Plant Regeneration from Suspension Cultures Of Rice (Oryza sative L.)

Abstract

Suspension culture was established from root segments of rice (Oryza sativa L.) cul-tures in Murashige and Skoog's (1962) medium supplemented with 2.0mg/1 2.4-dichloro-phenoxyacetic acid (2, 4-D) and 2g/l casein hydrolysate. The suspensions were composed of cells rich in cytoplasm with a potential for division and of elongated cells which contained large vacuoles and could not divide. Suspension cultures which were maintained L0r more than 2 months in liquid medium were plated on agar medium containing 0.5 mg/l kinetin and 2g/l casein hydrolysate. Embryogenic calli emerged from the plated suspension cultures. Plantlets were formed from the embryogenic calli by transferring them onto the medium repeatedly. The capacity for plant regeneration decreased in the advanced subculture passages in liquid medium. However, repeated transfer of the embryogenic calli to new regeneration medium promoted plant regeneration efficiently even in long term suspension cultures.