Fig. 4.

Response of the ahp double and triple mutants to treatment with exogenous ABA. Seeds were sown on germination medium-1% sucrose containing the indicated ABA concentrations; germination rates were quantified after 4 d of incubation by counting the number of open cotyledons. Error bars indicate SEs that were calculated from the results of four independent experiments. Asterisks indicate significant differences as determined by a Student’s t test analysis (*P < 0.05, **P < 0.01, ***P < 0.001).