Content of RCS in the epidermal tissues of WT and AER-OE plants P1#11, P1#14 and P1#18 treated with or without 50 µM MeJA for 30 min. Excised leaves of 5- to 7-week-old tobacco plants were blended for 25 s, and epidermal tissues were collected and floated on a stomatal bioassay buffer solution containing 5 mM KCl, 50 µM CaCl₂ and 10 mM MES-Tris, pH 6.15, for 2 h in the light followed by the addition of MeJA. Error bars represent standard error of mean (n = 5). Differences among treatments were analyzed by Tukey’s test: P < 0.05.