Effect of growth regulators on callus induction in Rice embryo culture

An experiment was conducted to study the effect of growth regulators on callus induction in rice embryo culture. In this experiment, caullogenesis was initiated from the matured seeds of seven indica rice varieties viz., TRY 1, TRY 2, Pokkali, CSR 10, W.Ponni, BPT 5204 and IR 29. The medium used for this callus induction was Murashige and Skoog (1962) commonly referred as MS medium with six different combinations of growth regulators viz., MS+2,4-D 25mMl-1, MS+2,4- D 20mMl-1, MS+2,4-D 15mMl-1, MS+2,4-D 10mMl-1, MS+2,4- D 15mMl-1+ KIN 2.5mMl-1, MS+2,4-D 10mMl-1+ KIN 2.5 mMl-1 Among the above combination of the growth regulators, MS + 2 mMl-1 2,4,D + 0.5 Kinetin performed well irrespective of all the genotypes. Analysis of variation showed that the genotype and medium are significantly different from each other and the interaction between Genotype X Medium also highly significant. Among the seven genotypes, Pokkali was significantly at (1%) superior for callus induction (63.57%) followed by W.Ponni (53.96%). The genotypes TRY 2 (51.70 %), TRY 1 (50.87) and CSR10 (49.22) are significantly at (5%) on par with each other. The well developed callus was transferred to regeneration medium for regeneration. The medium combination of MS +Kin 5mMl-1 + BAP 5mMl-1 + NAA 0.5mMl-1 recorded maximum average regeneration frequency of 57.25 percentage and higher response than the others. Among the varieties, Pokkali showed maximum regeneration frequency of 39.41 per cent and CSR 10 recorded minimum regeneration frequency of 20.23 per cent.