Effects of Exogenous Salicylic Acid on Physiological Properties of Tomato Seedlings Under Salt Stress

Taking the seedlings of tomato varieties 'Tianyuan No.6'(salt-sensitive) as materials,the effects of different concentrations of extraneous source salicylic acid(SA)(10,50,150,300 mg/L) on superoxide dismutase(SOD) activity,MDA content,root activity,soluble protein content,soluble sugar content and the chlorophyll content of the tomato seedlings under NaCl stress(100 mg/L) were studied.The results showed that NaCl could inerease the activity of superoxide dismutase(SOD) and the content of MDA,soluble protein and soluble sugar,while decrease the content of chlorophyll and root vigor,but after further treatment with SA 50 mg/L,compared to only dealed with NaCl,MDA content decreased by 21.35%,while the activity of SOD and the content of soluble protein and sugar respectively increased by 14.15%,74.30% and 33.71%,and it prevented the decrease of chlorophyll and root vigor with 26.88% and 82.03%.