Fig. 5

Reactive oxygen species (ROS), antioxidant enzyme activity, and antioxidant gene expression in WT and SikCOR413PM1-overexpressing cotton plants under cold and drought stress. (A) O₂⁻ content; (B) H₂O₂ content; (C) SOD activity; (D) GhSOD expression; (E) POD activity; (F) GhPOD expression; (G) CAT activity; (H) GhCAT expression; (I) GST activity; (J) GhGST expression. The data shown for the WT are means of three replicates, whereas those for the transgenic plants are means of three different lines. Bars represent standard deviations (SDs). * and ** indicate significant differences relative to WT cotton plants at P < 0.05 and P < 0.01. The expression leve at 0h (control time point) was defined as 1.0