Effect of genotype, explants, growth regulators and sugars on callus induction in cotton (Gossypium hirsutum L.)

Ten cotton (Gossypium hirsutum L.) genotypes were chosen for tissue culture. Callus initiation was genotype dependent, and R405-2000 has the best callogenesis response. Callus was induced from three media, the percentage of callus induction and dry weight of callus varied, but MS was the best callogenesis medium. It appeared that it was much easier to induce callus from hypocotyl than cotyledon or root explants. Induction callus of cotton was varied with hormone regimes. In effect, a proper combination of 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin (KIN) promoted the callus initiation. Glucose was the best sugar to promote the production of callus. However, the concentrations of glucose were critical to the induction of callus. The optimum glucose concentration for callus induction was 40 g/L. The best medium for the proliferation of callus was MS medium with 0.1 mg/l 2,4-D, 0.5 mg/l KIN and 4% glucose. An efficient protocol for the production of high frequency callus of cotton has been developed.