The constitutive expression of ThbZIP1 decreases ROS levels and enhanced GST activity. A, B: The leaves from Col-0 and transgenic plants were pretreated with NaCl, mannitol, or ABA, and were stained with NBT to visualize O2-(A), or were stained with DAB to visualize H2O2(B). C: Analyses of ROS production in intact guard cells of transgenic and Col-0 plants indicated by H2DCF-DA. Epidermal peels were loaded with H2DCF-DA after the incubation with 10 μM ABA or 150 mM NaCl for 2 h. (1) peel cells imaged under bright field; (2) ROS in guard cells were detected by H2DCF-DA (ROS shown as green fluorescence); (3) Chloroplast in the leaves that shown as red fluorescence; (4) merge of bright field and fluorescence (chloroplast shown as red fluorescence). D: Detection of ROS accumulation in root tips of transgenic and Col-0 plants using H2DCF-DA staining method. E: Measurement of H2O2 level in transgenic and Col-0 plants. F: Comparison of GST activity between Col-0 and ThbZIP1-transformed plants. All experiments were repeated three times. Data are means ± SD from three independent experiments. * Significant (t test, P < 0.05) difference compared with Col-0 plants.