Salicylic Acid Mitigating the Inhibition of Low Temperature Stress to Soybean Seedlings

Using soybean Zhongdou-31 as the material,effects of different concentration of salicylic acid(SA) on the growth of soybean seedling under 4℃ low-temperature stress was studied by hydroponic culture.Under low-temperature stress,The content of chlorophyll,soluble proteins and the root activity were significantly decreased;the contents of proline,soluble sugar,MDA and the activities of SOD and POD were significantly increased(P0.01).When the saybean seadlings were suffered from low-temperature stress for 2 days,exogenous SA significantly increased the contents of chlorophyll,soluble proteins,soluble sugar and proline,the root activity and the activities of SOD and POD,while significantly decreased MDA content(P0.01).The results showed that exogenous SA could effectively keep cytomembrane stabilization.and reduce the damage from membrane lipid peroxidation.Hence,mitigate the harmful effects from low-temperature stress on plants,with the optimal concentration of 1.5 mmol·L-1 SA.