In vitro Culture and Induction of Axillary Shoot Proliferation in Papaya (Carica papaya L.)

Papaya (Carica papaya L.) an important fruit crop has three sex types i.e. male, female and bisexual. Papaya \nplants derived from seeds are not genetically true-to-type. Vegetative propagation through grafting and \nrooting of cuttings are inefficient in generating large amount of planting stock Micropropagation by the in \nvitro technique is preferred. Though micropropagation of papaya has been successful, the rate of shoot \nmultiplication is still low and cannot fulfill the demand of large-scale application. This project was carried \nout with the objective to develop a protocol for establishment of contamination-free and viable culture and then to induce axillary shoot proliferation. An effective surface sterilization protocol has been developed by exposing explants obtained from rooted cuttings grown inside a plant house in 20% Clorox for 15 minutes. Shoots proliferated in medium supplemented with 0.5 mglL BAP and 0.1 mglL NAA. The temporary immersion system was found more efficient than the solid medium for shoot proliferation. Roots were induced in shoots cultured in medium containing IBA at 2.0 mglL.