EFFECT OF GROWTH REGULATORS ON CALLUS INDUCTION FROM CYCLEA PELTATA (LAM.) HOOK. F. THOMS.

Objective: To evaluate the effect of nutrient media and growth regulators on the stem explants of Cyclea peltata followed by the histological observations for the induction of callus.Methods: The stem explants were inoculated on to MS, B5 and Nitsch media to check the suitable nutrient medium for the in vitro culture. Growth regulators such as 2, 4 – D, NAA, IAA, BAP and Kn were added to MS medium prior to the inoculation of stem explants and observed for the induction of callus, nature and color/pigmentation of the callus and initiation of roots and shoots. Callus induction was confirmed by histological observations.Results: The young stem explants of Cyclea peltata cultured on MS medium supplemented with different concentrations of growth regulators showed the induction of callus. The callus obtained on the medium supplemented with either 2, 4 –D alone or in combination with BAP/Kn was yellowish cream and friable whereas, the callus obtained in the medium fortified with NAA/IAA alone or with BAP/Kn was compact and light to dark green in color. NAA (2mg/l), 2, 4 – D + BAP (1 + 3mg/l), 2, 4 – D + Kn (1 + 2, 2 + 0.1mg/l), NAA + BAP and IAA + BAP (3 + 2mg/l and 0.1 + 0.5mg/l) of concentrations induced significantly a higher number of calli. The histological study revealed the induction of callus from the cambial region of the explants.Conclusion: The study revealed the induction of callus from the cambial cells of stem explants of Cyclea peltata when cultured on MS medium supplemented with combinations of auxin and cytokinins.    Key words: Cyclea peltata, auxin, cytokinin, callu