The hydrolytic enzyme α-amylase (EC 3.2.1.1) is produced mainly in aleurone cells of germinating cereals, and the phytohormone gibberellin (GA) is essential for its induction. However, in rice ( Oryza sativa L.), sulfuric acid (H 2SO 4) induces α-amylase production in aleurone tissue even in the absence of GA. Here, the pre-treatment of rice aleurone cells with H 2SO 4 and incubation in water induced α-amylase activity, as if the cells had been incubated in GA solution.