Effects of exogenous nitric oxide donor on antioxidant metabolism in wheat leaves under aluminum stress

With the enhancement of aluminum stress, the content of chlorophyll in wheat seedlings (Triticum aestivum L.) decreased dramatically. At 0.2 mM AlCl₃, the chlorophyll content halved. The aluminum-induced decrease in chlorophyll content could be alleviated by exogenous nitric oxide donor, sodium nitroprusside (SNP) in a dose-dependent manner. Treatment with SNP dramatically promoted the activities of superoxide dismutase, catalase, ascorbate peroxidase and increased the proline content, whereas it decreased hydrogen peroxide and malondialdehyde and maintained the level of soluble protein as compared with water controls. Therefore, NO donor enhanced the antioxidant capacity in wheat seedlings under aluminum stress.