Effects of PP333 on bulbing culture of garlic’s test-tube seedings

In vitro experiments were carried out, using test-tube seedings of garlic stem tip as explants and taking MS as basic culture medium.The results showed that PP333 have a significant effect on formalion of garlic bulb and enlargement in vitro. Within the 2～8 mg/L concentration range, raising concentration could inhibit the formation and differentiation of the bulb, the leaves and roots were shortened and thinned. The 6 mg/L PP333 was the optimal treatment concentration for inducing formation and developmen of bulb. Variations in contents of endogenous bormone indicated that after PP333 treatment, ratio of IAA to ABA inside leaf sheath in the test-tube garlic seedlings dropped suddenly, the greater the decrease, the better the expanding in the formation of bulb.