Combination effects of nitrogen,phosphorus,potassium and organic manure on winter wheat in dryland of the Loess Plateau

The effect of different fertilizing treatments on dryland wheat yield and water and fertilizer use efficiency was studied.The results show that: The combination of N and P application has the highest fertilizing contribution rate,with a wheat yield of 5 099.8 kg/hm2 and an increasing rate of 21.5%;the yield-increasing rate of the combination of N and P application is 14.0% and 18.4% higher than that of N application and P application separately,and there is obviously positive interaction;the increasing rate of wheat yield of the single application of organic manure is 6.63%,4.12% and 11.3% higher than that of the combination of N and M,P and M,NP and M respectively.Fertilizer complication application can increase wheat yield,water use efficiency and fertilizer utilization,and the complication application of organic manure and N and P can increase fertilizer use efficiency of N and P by 17.71 and 12.55 percentage points;the combination of N and P can both increase the fertilizer use efficiency of N and P,with15.53% of the contribution ratio of fertilizer component of N and 12.26% of P,which can reduce water consumption coefficient by 21.4%,and increase water use efficiency by 17.57%.