Fig. 1. The phenotypes of the tagging mutant ahs1. (A) Growth of ahs1 in soil. Plants were grown in soil for three weeks. (B, C) ABA sensitivity of ahs1. Seeds were germinated and grown in a medium containing 0.75 μM ABA for seven days (B). For root elongation assay in (C), seeds were germinated and grown in an ABA-free medium for three days, the seedlings were transferred to media containing various concentrations of ABA, and primary root growth was measured five days after the transfer. Experiments were carried out in triplicates (n = 6), and the small bars indicate the standard errors. (D, E) Drought tolerance of ahs1. Water was withheld from 11 day-old seedlings for 11 days, after which they were re-watered. The picture in (D) was taken two days after re-watering. The survival rates in (E) represent the means of three independent experiments (n = 20 each), and the small bars indicate the standard errors. (F, G) Salt tolerance of ahs1. Seeds were germinated and grown in media containing 100 mM or 150 mM NaCl for four days, and seedlings with green cotyledons were then counted. All experiments were conducted in triplicates (n = 50), and standard errors are indicated by the small bars. (H) A diagram showing the position of T-DNA insertion in the AHS mutant. (I) The expression level of AtMYB52 (At1g17950) (MYB52) was determined by RT-PCR. Actin-1 was used as an internal control.