With calluses of hermaphrodite papaya as the tested material and MS as the basic medium, the effects of different plant growth regulators and their combinations on adventitious bud induction of calluses and rooting induction of sterile buds were investigated. The results showed that 6-BA and TDZ all showed certain induction effect on callus differentiation of papaya; the induction effect of 6-BA was better than that of TDZ, and the optimum concentration of 6-BA was 0.05 mg/L. GA3 could promote the induction effect of 6-BA for on callus differentiation. The optimum medium combination for inducing the callus differentiation of papaya was MS ＋ 6- BA 0.5 mg/L ＋ GA3 1.0 mg/L. Compared to NAA, IBA was more suitable for inducing the rooting of adventitious buds. The optimum rooting-induction medium combination was MS ＋ IBA 0.3 mg/L.
