Effects of Different Soil Moisture on Growth,Grain Yield and Water Use Efficiency of Spring Wheat Under Drip Irrigation

A soil moisture controlled experiment under drip irrigation was conducted under the ecological and climatic conditions of South Xinjiang to study the effects of soil moisture on shoot growth, grain yield and water use efficiency(WUE) of spring wheat with tall variety of Xinchun 19 and dwarf variety of Xinchun 22 . The results indicated that the moisture-sensitive stage of spring wheat was at jointing to flowering stage and water deficit would significantly affect plant height, biomass, leaf area and yield components. In all water treatments, the soil relative moisture content of T2 at emergence to jointing, jointing to flowering and flowering to milk maturation being 65%-70%, 70%-75% and 65%-70%, respectively, showed a highest values of grain yield, WUE and harvest index(HI). The soil relative moisture content of T4 at emergence to jointing being 45%-50% and at other stages being the same as T2, was the secondary in grain yield, and its WUE, HI, number of kernels per spike and grain weight were no significant difference compared with T2, so T4 was economically feasible in deficit irrigation. Different genotypes had different response to soil moisture. Dwarf variety of Xinchun 22 was susceptible to soil moisture, and its water consumption of each treatment was below Xinchun 19, so it was a water saving cultivar. Studies showed that the suitable amount of drop irrigation for dwarf variety and tall variety in South Xinjiang were 318.86 mm -368.72mm and 394.52 mm -458.14mm respectively.