Fig. 1

Differences in stomatal conductance, transpiration water loss and stomatal dynamics for accession identified as drought tolerant (284, 510 and 521 identified with plain colours on the histograms bars of all the figures) and drought sensitives (502, 506 and 545 identified with ornamented wefts on the histogram bars of all the figures). a. Stomatal conductance values measured in the field. Graphic indicates a representative measurement (May 2018; rainfed condition; “La Canaleja” Madrid), recorded in triplicate on at least 6 plants of each variety. b. Water content and transpiration water loss from detached vetch leaflets of greenhouse-grown plants 3 h after detach. One-week-old vetch varieties were grown with (control) or without water (drought) for additional 3 weeks, before being dried and weight at 3 h. Relative leaf weight was expressed as a percentage based upon the initial fresh weight (% FW). Three independent experiments; n = 20 leaflets each. Statistical differences (ANOVA and Tukey HSD test) are only referred to same time, for simplification. c. Analysis of stomatal index (number of stomatal complex×100/number of total epidermal cells). Cell analysis of abaxial leaf epidermal layers (4-week -old leaves) of different greenhouse-grown genotypes analysed by microscopy. d. Stomatal closure by drought. Stomatal apertures were measured on epidermal peels of leaves from greenhouse-grown 4-week-old plants grown in control (white columns) or drought (black columns) conditions. Values obtained from triplicate experiments (n > 60). e. ROS production was analysed by measuring carboxifluorescein diacetate fluorescence levels in guard cells from greenhouse-grown 4-week-old plants grown in control (white columns) or drought (black columns) conditions. Experiments were carried out in triplicate. a-e. Values are means ± sd. Different letters indicate significantly differences analysed by ANOVA and Tukey HSD post hoc test post-test; p < 0.05