Effects of Exogenous Salicylic Acid on Physiology of Rice Seedlings under Salt Stress

The effect of extraneous salicylic acid( SA) on the tolerance responses to NaCl stress in rice seedlings was studied. Rice seedlings were sprayed by 1mmol / L SA and were then stressed under 100 mmol / L NaCl for 0- 48h. The results indicated that exogenous salicylic acid significantly increased the contents of proline( Pro) and soluble protein and also increased the activities of protected enzymes such as superoxide dismutase( SOD) and peroxidase( POD) in rice seedlings leaves,but decreased the content of malondialdehyde( MDA) in rice leaves. It is proposed that exogenous salicylic acid participated in the tolerance responses to NaCl stress in rice,which enhanced the tolerance of rice against NaCl stress by regulated the activity of antioxidant enzymes and decrease damage degree of salt stress.