Figure 3. Effect of exogenous trehalose on the activities of antioxidant enzymes in rice seedlings with or without Cu stress.

(a) superoxide dismutase (SOD), (b) catalase (CAT), (c) glutathione peroxidase (GPX), and (d) glutathione reductase (GST). Control, Tre, Cu, and Tre+Cu correspond to control, 10 mM trehalose, 100 μM CuSO₄, and 10 mM trehalose + 100 μM CuSO₄, respectively. Bars represent standard deviation (SD) of the mean (n = 3). Different letters indicate significant differences among treatments at p < 0.05, according to Duncan’s multiple range test.