Effect of nitrogen fertilizer application on yield and nutrition uptake of winter wheat planted in straw return field

【Objective】A field experiment aiming at the effect of nitrogen fertilizer application on yield and nutrition uptake of winter wheat planted in straw return field was conducted,to improve nitrogen application on field with straw return.【Method】A wheat cultivar,Zhoumai 23,was used in split block design field with 4 replicates.A total of 5 main treatments were coded as N0,N84,N168,N252,and N336 for nitrogen fertilizer application(0,84,168,252,and 336kg/hm2 nitrogen fertilizer applied,respectively)and return of maize straw was coded as vice treatment.【Result】Compared with treatments without straw return,wheat yields of S+N(straw return and nitrogen application)decreased,but differences were not significant statistically.Nitrogen fertilizer use efficiencies and agronomic nitrogen use efficiencies of S+N treatments were higher than those of N treatments by 3.29%-24.46%and 15.04%-30.05%,respectively.With the increase of nitrogen application rate,nitrogen contents in wheat grain,leaf and glume and potassium contents in wheat leaf and glume of S+N treatments increased significantly,while phosphorus contents in wheat glume decreased slightly.Nitrogen application rate had no significant affect to phosphorus contents in leaf and grain,and potassium contents in grain.【Conclusion】Returning straw to field had positive effects on nitrogen fertilizer application in winter wheat field under the experimental conditions,and no more than 336kg/hm2 was the suggested nitrogen application rate together with straw return.