Efficient callus Regeneration and Multiple shoot induction in Brassica juncea var. Pusa Jaikisan

In the present work an efficient regeneration protocol has been established for mustard (Brassica juncea var Pusa Jaikisan) using hypocotyls of in vitro grown seedlings for callus induction and multiple shoot induction. Different concentrations of phytohormones, auxin (NAA: Naphthalene acetic acid) and cytokinins (BAP: Benzylaminopurine) were used. For callus induction and plant regeneration, the MS medium was supplemented with 3% sucrose and BAP (6-benzylamino purine) and NAA (Naphthalene acetic acid) at different concentrations of 0.2, 0.5, 1.0, 1.5, 2.0 and 2.5 mg/L. About 91.6-100% formation of callus from hypocotyls explants were observed in the MS media supplemented with BAP at 0.5-1.0 mg/L + NAA at 0.5-1.0 mg/L. In these conditions, the explants also produce more number of shoots ranging from 7 to 20 shootlets/explant. It was also observed that at MS medium with BPA at 2.0-2.5 mg/L + NAA at 0.5 mg/L, all the explants (100%) produced callus but shoot induction was found to be very less and about 8.3-33.3% explants showed shoot formation with as less as 1-2 shootlets/explant. This protocol can be further explored for transformation of mustard for incorporation of specific genetic traits for improvement of crops.