The Function Of The Nitric Oxide In The Soybean Under Aluminum Stress

About30percent of the world’s total land area are acidic soils, bout50%of potential arable land is acidic. In china, about21%of arable land is acidic. In general, aluminum (Al) in the form of aluminum silicate minerals and oxides exist in the soil. When soil is acidified, Al will be released from the solid phase in to the soil solution or in the form of exchangeable Al adsorbed at the surface of the soil, so that the concentration of the activated Al is increased. For most plants, micro-molar concentrations of the actived Al is able to significantly inhibit root elongation. It is a problem that Al toxicity has been represented one of the major constraint on plant growth in acid soil worldwide. Al-induced citrate exudation has been identified as an Al-resistance mechanism in plant. Salicylic acid (SA), whick considered as a small signal molecule, can play an important role in regulated the plant resistance. It has been proposed that SA can involve in modulation of acclimation responses to abiotic stresses such as drought, salinity, heat shock, low temperature and so on. Nitric oxide (NO) is a important signaling molecules in vivo. it not only regulates plant seed germination and seedling growth. but also play an important role in the resistance of plants. Studies have shown that NO plays an important role in resistance of Al. Soybean is considered a pioneer crop for improving redients acidic soils, which is always occupy an important position in China’s agricultural economy. Thus, this study was to research the relationship of NO and SA under Al stress. Results were as follows:(1) Lateral root pay an important role in the plant under Al stress;(2) When the plant under Al stress, it will produce NO distribution throughout the plant roots, in order to reduce the toxic effects of Al;(3) The low concentration of SNP alleviated the inhibitory of soybean root elongation under Al stress:(4) SNP can alleviate the poison of Al on soybean, but it can not decreased accumulation of Al in roots and decreased citric acid content and secretion of the soybean;(5) SNP can reduce oxidative stress.it not only can Improve the activities of antioxidant protective enzymes.but also regulate the metabolism of oxidative;(6) SNP can increase the concentration of the SA and SAG in roots:.(7) The main synthetic spaces of SA is the root.