Tissue Culture Protocol for In-vitro Propagation of Papaya (Carica papaya L.)

Papaya is slowly emerging from the status of a homestead crop to that of commercial crop due to increasing awareness of multifold uses of papaya. Its cultivation is encountered with the problem of its dioecious nature. Micro propagation represents the only economic way of continuously producing uniform planting material of known sex. The studies on in-vitro propagation of papaya (Carica papaya L.) was carried out at the Department of Pomology and Floriculture, College of Agriculture, Vellayani. The propagation studies were carried out by enhanced release of axillary buds in Papaya variety Pusa Nanha. Apical buds and lateral buds from seedlings and mature plants were used as explant. Explants were subjected to different treatments of plant growth substances for culture establishment and shoot proliferation. The study revealed that full strength MS medium supplemented with sucrose 30.0 g/l and agar 6.5 g/l under light condition produced highest shoot number and longest shoot in papaya. Application of BA 0.50 mg/l along with NAA 0.1mg/l was found to be better for initial culture establishment and proliferation. Application of amino acid, glycine, 100.00 mg/l resulted in highest shoot proliferation rate, while highest shoot length was obtained from arginine100.0 mg/l. Addition of activated charcoal 0.05 per cent and Cobalt chloride 5.0 mg/l increased the shoot proliferation rate and shoot length in papaya. In vitro rooting was more in full strength MS medium supplemented with IBA 3.0 mg/l, sucrose 30.0 g/l and activated charcoal 0.05 per cent.