Effect of hormones, explants and genotypes in in vitro culturing of sorghum

In vitro culturing of sorghum is very much influenced by genotypes,explants, media composition and hormones. Among the genotypestested CO 25 was found to show high frequency of callus inductionand regeneration. Regeneration efficiency of embryogenic calli fromCO 25 was found to be greater (88-98%) than that of calli derivedfrom other explants (Immature inflorescence, Mature embryo andShoot tips) of different genotypes (CO 26, TNS 586 and CO-S-28).Out of the different media tried for callus induction and regenerationof sorghum, I6 medium + kinetin 0.5 mg l-1 + 2,4-D 2 mg l-1 showedhigh frequency of embryogenic calli from immature embryo ofCO25. Regeneration medium I6 + Kinetin (1.0) + NAA (0.5) +casein hydrolysate at levels of 250 mg l-1 and 500 mg l-1 was foundto best medium composition for regeneration. An efficient protocolhas been developed from suitable explant and genotype for callusinduction, regeneration of sorghum and thus to produce transgenicplants for biotic and abiotic resistance.