Abstract
5-methyltryptophan (5MT) resistant cell lines, SAR-1, SAR-2 and SAR-3 were selected from anther derived calli of rice (Oryza sativa L. var Sasanishiki). Among these selected cell lines, two (SAR-1 and SAR-3) were stable in 5MT resistance and accumulated free tryprophan at least 50 times higher than that of the unselected cells. The resistant cell lines, however, were not able to produce plants on regeneration medium. Protoplasts from SAR-3 suspension culture cells were fused using dextran method with protoplasts of 5MT sensitive cells (Oryza sativa L. var. Hanahikari) which had the ability to regenerate plants. Prospective somatic hybrids were selected by culture on selection medium contianing 5MT and then on regeneration medium for plant formation. Three albino plants suspected to be somatic hybrids were regenerated from selected colonies. Calli, initiated from the plants, showed resistance to 5MT intermediate between that of the two parents. These results indicate that the combinaion of 5MT resistance ancl plant regeneratlon ability can be used as a complementary marker for selection and identification of somatic hybrlds in rice plants.
