Effects of different plant growth regulators on in vitro callus induction in physic nut (Jatropha curcus L.)

Jatropha (Jatropha curcas L.) is an oil bearing crop growing in tropical and subtropical parts of the world. The present study was undertaken to investigate the effects of different plant growth regulators on in vitro callus induction in physic nut (J. curcus). In the present study, it was observed that all the explants viz., leaf lamina, petioles, nodal segments and cotyledonary nodes showed good callus induction responses on various culture media thus tried. Leaf lamina and petioles showed 100.0% callus induction responses on different MS media supplemented with auxins and cytokinins alone or in combinations whereas, nodal segments and cotyledonary nodes showed maximum 89.6% and 83.9% callus induction respectively. The presence of 2, 4-D in culture media with auxins or cytokinins was essential for good callus growth. Among different explants tried, leaf lamina was the best responding explants and MS-13 media supplemented with 5×10-6 M NAA and 10-5 M 2, 4-D is the best callusing and growth supporting medium. However, the regenerative competence of the callus tissues can differ depending on the type of explants used because certain types of plant tissues have more favorable regeneration responses than others. Callus induction rate from all explant types was highest than other reports. The results obtained in the present study would facilitate the high callus induction and regeneration responses in J. curcus for its improvement using biotechnological tools