Effects of Silicon on Antioxidant Enzymes Activities and Ions Uptake of Rice Seedlings under Salt Stress

The effects of silicon on antioxidant enzymes activities and ion content of rice under the salt stress were studied by the method of K2SiO3 foliar spraying.The results showed that the SOD and POD activities were significantly decreased and the MDA content was significantly increased under salt stress.1.0-2.0 mmol L-1 K2SiO3 treatment significantly promoted SOD and POD activities,reduced the MDA content and alleviated the level of membrane lipid oxidation in rice seedlings under the salt stress.Salt stress significantly reduced K+,Ca2+,Mg2+ uptake of shoot and root but increased Na+ uptake.1.5-2.5 mmol L-1 K2SiO3 treatment significantly increased the K+,Ca2+,Mg2+ accumulation of shoot and root,but decreased Na+ accumulation.1.5 mmol L-1 was the best concentration of silicon to alleviate the salt injury of rice.In addition,the SiO2 content of rice stalk was improved after silicon treatment,so the stalk was lodging resistant.