Effects of Exogenous Spermidine on Anti-oxidative Enzyme Activities in Rice Seedling Roots under Salt Stress

The effects of exogenous spermidine on anti-oxidative enzyme activities,contents of proline and soluble protein and root vigor in roots of rice cultivars(Pokkali,salt-tolerant and Peta,salt-sensitive) under salt stress were studied in this paper.The results showed that the activities of SOD,POD and CAT and contents of proline in roots of two rice cultivars with exogenous spermidine treatment under salt stress were increased,while the O2-· producing rate and contents of MDA were decreased.Moreover,the decline of contents of soluble protein and root vigor in roots of rice cultivars was alleviated by exogenous spermidine treatment.These results suggested that exogenous spermidine could alleviate the injury of NaCl stress in roots of rice cultivars.Moreover,the alleviation effect of exogenous Spd in roots of salt-tolerant was less than that of salt-sensitive Peta under salt stress.