Regeneration Enhancement in Tissue Culture of Indica Rice’s through Partial Desiccation and Chemical Supplements

Indica rice genotypes are known to be recalcitrant to culture and several efforts have been made over years to enhance their callus induction and regeneration rates. Some of the effective approaches employed include use of phytohormones in a proper combination and proportion, amino acids like tryptophan, proline or supplements like casein hydrolysate and yeast extract etc. which have shown positive improvements in callus induction but enhancement of regeneration rates stills remains a major bottleneck in Indica rice tissue culture. Keeping in view that the rates of callus induction and regeneration are not related, an effort was made to enhance regeneration potential of the Indica rices through supplementation of media with chemicals like silver nitrate and adenine sulphate, sugar alcohols like sorbitol and subjecting the calli to stress through partial desiccation prior to regeneration. The results suggest that significant improvement of callus regeneration rates is feasible that is genotype independent as a twofold increase of regeneration rates can be induced in most of the genotypes through partial desiccation. The results can widen the scope of Indica genotypes that are used for development of transgenic Indica rices.