Optimization of conditions for fast propagation of papaya seedling stem

【Objective 】The effects of hormones on differentiation of papaya seedling stem were explored to provide technical references for large-scale fast propagation of papaya. 【Method 】The best seed treatment method was screened out of four different treatments,then the seedlings stems were used as explants to optimize the inducing medium,proliferation medium and rooting medium. 【 Result 】 Seeds soaked in equal volume mixture of 6- BA1. 0 mg / L and GA31.0 g/L for 18 h before sowing obtained the highest germination rate at 93.3 % and low rate of pollution at 3.3%. Induction medium MS +6-BA0.5 mg/L +NAA0.2 mg/L was suitable for papaya stem bud differentiation. The optimum medium for proliferation culture was MS +6-BA 0.2 mg/L +NAA 0.1 mg/L +sucrose 40.0 g/L,in which the proliferation coefficient reached 4.3, and the optimum medium for root inducing was MS+IBA1.0 mg/L+KT0.05 mg/L+AC 2.0 g/L.【 Conclusion 】 MS + 6- BA 0. 5 mg / L + NAA 0. 2 mg / L, MS + 6- BA 0. 2 mg / L + NAA 0. 1 mg / L + sucrose 40. 0 g / L and MS +IBA 1.0 mg/L +KT 0.05 mg/L +AC 2.0 g/L can be used as inducing medium,proliferation medium and rooting medium respectively for tissue culture and fast propagation of papaya seedling stem.