Effects of Salicylic Acid on the Growth and Physiological Property of Wheat Seedlings under Hg~(2+) Stress

To understand the regulation effects of applying salicylic acid(SA)on the resistance to Hg2+of wheat seedlings,wheat cultivar Yumai 58was used as the experimental material in this study, the effects of SA on the growth of wheat seedlings under Hg2+stress were studied through hydroponic method.The results showed that after application of SA,the root length,plant height,fresh weight per plant,the contents of chlorophyll content,soluble proteins and proline,the root activity and the activities of antioxidant enzymes of the Hg2+stressed wheat seedlings were significantly increased, while,the content of malonaldehyde and the production rate of superoxide anion were significantly decreased(P0.01).Which suggested the harmful effects of Hg2+stress on wheat seedlings were mitigated by applying SA through increasing the contents of soluble proteins and proline in the wheat seedlings and increasing the activities of the antioxidant enzymes to reduce the damage from peroxidation of membrane lipid,and the optimal SA concentration was 40mg·L-1.