Induction and proliferation of callus derived from fruits of different varieties of Capsicum annuum

Callus was initiated on Murashige and Skoog (MS) medium containing different combinations of growth regulators or different concentrations of vitamins from pericarip of six varieties of Capsicum annuum differing in their capsaicin content. Callus derived from pericarp of low capsaicin containing varieties was snowy white, friable and showed excellent growth. Callus initiation was delayed (10-15 days) in Punjab Lal, which had very high fruit capsaicin content (7.0 mg g(-1) DW). It also showed relatively slow proliferation although callus obtained was white and friable. Several different media were tried to improve the initiation and the proliferation of the callus in this variety. Callus growth improved greatly by doubling the concentration of MS salts. Initiation time was reduced to 4-6 days by adding 10 mg l(-1) NAA and 0.5 mg l(-1) Kin in MS medium. Other combinations of growth regulators or increase in concentration of vitamins or activated charcoal (0.1%) resulted in poor callus growth and callus texture. Of all media tried, MS medium containing 2 mg l(-1) 2,4 D and 0.5 mg l(-1) Kin was the best for callus initiation and proliferation.