Effects of Brackish Water Salinity on the Soil Salt and Water Movements and the Cotton Seedling Growth under Film Hole Irrigation

Use of brackish water is becoming more and more important in agricultural irrigation, and it has not been effectively utilized. The effects of brackish water on the soil salt and water movements and the emergence rate of cotton with different salinities of brackish water (0 g/L (control group-CK), 2, 3, 5 and 7 g/L) through film hole irrigation were examined. The results showed that: (1) the cotton emergence rate significantly decreased under the salinity of brackish water more than 5 g/L, whereas the brackish water salinity of 0-5 g/L barely affected the cotton seedling growth; (2) the leaf net photosynthetic rate (Pn) and transpiration rate (E) gradually decreased with the increasing salinity brackish water; (3) the soil salinity increases with the increase of salinity brackish water; and, as time increased, soil salinity gradually moved downward. The results suggested that high salinity of brackish water may have impacts cotton seedling growth. The results may have important significance on cotton plantations with brackish water film hole irrigation.