FC reduces ABA-induced H
level in guard cells. Guard cells of Vicia faba shown in image (A) were treated with CO2-free MES/KCl buffer alone for 3 h under light conditions (300 μmol m-2 s-1) at 25°C. Guard cells shown in image (B) were treated with 10 μM ABA, (C) with 0.1 μM FC, (D) 0.1 μM FC +10 μM ABA, (E) 100 units mL-1 CAT, (F) 100 units mL-1 CAT +10 μM ABA, (G) 10 μM DPI, (H) 10 μM DPI +10 μM ABA. (I) The average fluorescence intensity of guard cells in images (A–H), data are means ± s.e. Values in (I) with different letters are significantly different at P <0.05 based on Fisher LSD post hoc test. The guard cells shown in image (a–h) are the representative of guard cells shown in image (A–H). The insets show the bright-field images corresponding to the fluorescence images (a–h). Scale bars in image (H) and (h) represent 40 and 15 μm for images (A–H) and (a–h), respectively. The bar in inset of image (h) represents 8 μm for all insets. Each experiment was repeated at least three times, and the selected confocal image represented the same results from approximately nine time measurements.