Experimental Research on Crop Growth and Salinity of Soil under Light-saline Water Irrigation

Field irrigation experiment of different salt concentrations is conducted for wheat with normal quota and leaching quota in this paper,and crop growth,accumulation law of dry matter above the ground and crop yield.are also researched into.It is found that the soil salinity increases obviously in the definite deep zone when the salt concentration of irrigation water reaches the critical value.This critical value basically coincides with the salt concentration of irrigation water that restrains the crop growth and decreases the crop yield.Because the leaching irrigation can leach salt into deep layers,the resistance capacity to salt is enhanced through leaching irrigation.As a result,the soil salinity in the root area is decreased.By establishing a correlation between yield and salt concentration of irrigation water,the thresholds of salt tolerance for wheat is determined.The salt tolerance threshold of wheat in the normal quota is 4.0 g/L.In the leaching quota it is 4.5 g/L.The predicted value is basically accordant with the critical value.