Effects of calcium on growth and expression of soluble protein in cucumber seedlings under salt stress

A hydroponic experiment was conducted to study the effects of exogenous calcium on growth and soluble protein expression of salt sensitive cucumber cultivar Jinchun 2(Cucumis sativus L.) under salt stress.Exogenous Ca2+ significantly increased the biomass under 75 mmol/L NaCl stress(P0.05).The soluble protein content in cucumber leaf significantly was decreased by salt stress(P0.05),however,it was improved at sixth day of Ca2+ application(P0.05).The soluble protein content of cucumber root was increased first and then decreased under salt stress(P0.05),however it was decreased first and then increased after Ca2+ application(P0.05).The results of SDS-PAGE analysis showed that the expressions of twelve proteins with relative molecular weights of 8.75×104,7.79×104,7.57×104,7.41×104,6.51×104,5.43×104,5.05×104,4.47×104,4.07×104,3.14×104,2.60×104 and 2.15×104 changed obviously in cucumber leaves,and seven proteins with relative molecular weights of 8.11×104,7.66×104,4.69×104,4.52×104,3.95×104,2.38 ×104 and 1.68×104 in roots changed in roots under salt stress as well.