Figure 6.

Effects of ZnO NPs on antioxidant enzyme activity in rice leaves under chilling stress. Superoxide dismutase (SOD, A), catalase (CAT, B), and peroxidase (POD, C) of rice seedlings subjected to 0, 25, 50, and 100 mg/L of ZnO NPs under chilling stress were measured, respectively. The tests were repeated three times. The data given are the averages of three replicates, with the SD shown by the error bars. Different letters above error bars show the differences at p < 0.05. FW, fresh weight.