Effect of Salt and Drought Intercross Stress on Lipid Peroxidation and Activity of Cell Defense Enzymes in Leaves of Gleditsia sinensis Seedlings

Lipid peroxidation and activity of cell defense enzymes in leaves of one-yearold Gleditsia sinensis seedlings were studied under drought and salt stress.The results showed that under drought and salt stress,the content of MDA and electrolyte leakage appeared an increasing trend,the largest increase of MDA was 165%;the activities of SOD,POD,CAT increased at first and decreased later,the lowest activities compared with the highest,SOD decreased 70%,CAT decreased 80%,POD was not significant;as the prolonging of treatment,electrolyte leakage and content of MDA appeared an increasing trend;the activities of SOD,POD decreased;the activities of CAT increased at first and then decreased later.The comprehensive analysis indicated that under the intercross stress of salt and drought,the seedings of G.sinensis showed certain tolerate to salt and drought and this indicated that appropriate drought stress could increase the seedling resistant to salt stress.