Abstract: By the method of solution culture, wheat was used to investigate the effects of exogenous NO donor SNP on seed germination and seedlings physiological characteristics under Pb²⁺ stress. The results showed that Pb²⁺ treatment resulted in significant decreases in seed germination and seedling growth of wheat，and notable reduction in the levels of chlorophyll a, chlorophyll b and chlorophyll fluorescence, 25 μmol·L^-1 SNP could alleviate the inhibition of Pb²⁺ on these indexes. No significant changes in the activities of CAT and POD were observed in comparison with the control under Pb²⁺ stress. However, the application of SNP induced increases of CAT activity and soluble protein content in wheat seedlings under Pb²⁺ treatment. Therefore, exogenous NO could alleviate the poison of Pb²⁺ and enhance the adaptation of wheat seedlings to Pb²⁺ stress.

Key words: Pb²⁺ stress, seed germination, chlorophyll, soluble protein, wheat