Effects of different fertilization systems on yield of wheat and water and fertilizer use efficiency in the Loess Plateau.

Effects of different fertilization on yield of wheat and soil nutrient and water changes and its use efficiency were studied using a long-term experiment in rainfed lands of the Loess Plateau.The result shows that the best for the yield-increasing in the single applications is the application of the organic compound fertilizer(M),and its output can reach to 5265 kg/ha.The combined applications of organic fertilizer and chemical fertilizer increase the yield of wheat,and the highest yield is 5898.8 kg/ha under the NPM fertilization.Under the NPM combined application,wheat grain and stalk uptake the largest amounts of total N with the increase of 131.4 kg/ha compared to the single application of N fertilizer.The maximum fertilizer utilization is the combined application of organic fertilizer and nitrogen and phosphorus fertilizer,and the nitrogen utilization;nitrogen partial factor productivity,agronomic efficiency and physiological nitrogen utilization are 67.0%,49.16 kg/kg,36.97 kg/kg and 73.11 kg/kg.Different fertilization systems reflect the nearly same trend,that is: NNPNMNPM and have the significant differences among the treatments.Soil total nitrogen and available nitrogen are not significant difference between under the single application of N fertilizer and CK(no fertilizer),and the organic fertilizer can significantly increase the content of soil available K.In different fertilization systems,the water consumption of the NPM fertilizer can up to 558.3 mm,water use efficiency up to 31.5 kg/(ha·mm),and with the increase of water consumption at the same time,the soil appears dry trend.