Sodium uptake and carbon/nitrogen metabolism by different winter wheat genotypes during germination under salt stress.

The effect of salt stress on sodium uptake and accumulation,carbon and nitrogen metabolism and the ameliorative effect of calcium on wheat seed germination were studied.Results indicate that wheat seed germination is inhibited by 150mmol/L NaCl.Xiaoyan6is more tolerant than Shaan229during wheat germination.The ameliorative effect of exogenous calcium on the germination of the two wheat genotypes is different.Salt injury on Shaan229 is significantly reduced by the addition of 6 mmol/L Ca2+,but calcium has no ameliorative effect on Xiaoyan6.Salt stress can decrease proteinase and amylase activities during wheat germination.Xiaoyan6 enzyme activity is higher than that of Shaan229.Proteinase activity is improved by calcium while amylase activity is little affected by calcium.Na+ content in wheat seeds increases remarkably while K/Na ratio decreases significantly under salt stress.Na+ content of wheat seed is affected by exogenous calcium,but K+ content is little affected under 150 mmol/L NaCl and calcium.