Figure 3

Enhanced tolerance of CaREL1-silenced pepper plants to drought stress. (a) qRT-PCR analysis of CaREL1 gene expression in pepper leaves 0–24 h after treatment with 50 μM abscisic acid (ABA) or drought. (b and c) Increased leaf temperatures of CaREL1-silenced pepper plants in response to ABA treatment. Leaf temperatures after treatment with 50 μM ABA were measured using thermal imaging and representative images were taken (b). Data represent the mean ± standard error of three independent experiments (c). (d and e) Stomatal apertures in control and CaREL1-silenced pepper plants treated with ABA. Leaf peels were harvested from 4-week-old plants of each line and incubated in SOS buffer containing 0 μM or 20 μM ABA. Stomatal apertures were measured under the microscope and representative images were taken (d). Data represent the mean ± standard error of three independent experiments (e). (f) The drought-tolerant phenotype of CaREL1-silenced pepper plants. Control and CaREL1-silenced pepper plants were grown in pots for 6 weeks under well-watered conditions. Thereafter, watering was withheld for 11 days, followed by re-watering for 2 days. (g) Survival rates of control and CaREL1-silenced pepper plants after 2 days of re-watering. Data represent the mean ± standard error of three independent experiments, each evaluating 20 plants. (h) Transpirational water loss from the leaves of empty vector control and CaREL1-silenced pepper plants at various times after detachment of leaves.