Influence of GA₃ and ABA on germination of immature rice Bo II You 15 seeds were investigated.The results of treatments with different concentration of GA₃ and/or ABA and distilled water (as control,CK) were as follows.Among those treatments,GA₃ with 500 mg/L was the best to promote germination,and the germination rate could break through to 80% on the fourth day,which was 56% higher than that of CK.Treatment of ABA with more than 500 mg/L,could inhibit the germination markedly.When treated with both GA₃ and ABA,with the ratio of GA₃/ABA=1(50 mg/L),GA₃/ABA=1/2(10 mg/L),promoted the germination respectively,and made the germination rate get to 60% and 50% on the seventh day,which was 30% and 20% higher than that of CK.Further study indicated that such regulation of GA₃ and ABA on germination of immature rice seeds was closely related to the α-amylase activity.