Importance of various concentrations of auxins in in vitro regeneration of guar species

Abstract

Different explants of different species of guar ie. C. tetragonoloba cv. HG 563, C. serrata and C. Senegalensis viz. cotyledon, hypocotyls, cotyledonary node measuring 4-5mm obtained from asceptically grown seedlings were inoculated on the surface of culture medium. Embryo explants were excised from surface sterilized 10 day old green pods taken from net house and three explants per flask were cultured.

Direct shoot regeneration from hypocotyls was observed in medium adjuncted with 1mg/l BAP in C. serrata. Cotyledonary node produced multiple shoot on MS medium supplemented with 2mg/l BAP. C. senegalensis showed direct multiple shoot formation only from hypocotyl explants in medium supplemented with 1mg/l BAP. Maximum callus induction from cotyledon explant was evident in  C. serrata and C. senegalensis on MS medium with B5 vitamins and supplemented  2, 4-D (2mg/l). Hypocotyl explants of all the tested species of Cyamopsis showed very good callus induction response in media supplemented with 2mg/l 2, 4-D.

Half strength MS + NAA(2mg/l) was the best for rooting of shoots in C. tetragonoloba while ½ MS with 0.5 mg/l and 1 mg/l IBA supported best rooting in C. senegalensis and C. serrata.  C. tetragonoloba showed flowering in MS medium adjuncted with NAA (2mg/l) with BAP (2mg/l) from shoots obtained from cotyledonary node explant after 80-90 days of inoculation. In vitro  regenerated plantlets were  successfully transferred to paper cups.Micropropagation of C. serrata and C. senegalensis on the above media will help to produce true to type plants and reduce dependence on seeds for plant production.