Fig. 1.

Loss-of-function of AHP2, AHP3, and AHP5 results in enhanced drought tolerance. (A) Two-week-old WT and ahp2,3,5 plants were transferred from germination medium (GM) plates to soil and grown for an additional week. (B) Three-week-old plants were exposed to drought stress for 13 d and photographed 3 d subsequent to rewatering and after the removal of inflorescences. (C) For control purposes, 2-wk-old WT and ahp2,3,5 plants were transferred from GM plates to trays and grown under well-watered conditions in parallel with the drought test as shown in (B). (D) Soil relative moisture contents and relative humidity were monitored during the drought tolerance test (A and B). (E) Survival rates and SEs (error bars) were calculated from the results of three independent experiments (n = 30 plants/genotype). Asterisks indicate significantly higher survival rates than WT as determined by a Student’s t test analysis (***P < 0.001). (F) Two-week-old WT and ahp2,3,5 plants were transferred to soil in an alternate order and grown for an additional week. (G) Three-week-old plants were exposed to drought stress; plants were photographed 20 d after the withholding of water. (H) For control purposes, WT and ahp2,3,5 plants were grown in an alternate order in parallel under well-watered conditions.