Effects of nitrogen application on yield,nitrogen uptake in high-yield winter wheat and soil inorganic nitrogen accumulation

In order to establish the technical parameters of scientific nitrogen fertilization in winter wheat high-yield and high-quality product,a field experiment was conducted to investigate the effects of different nitrogen amounts and dressing ratios on grain yield,quality,and spatiotemporal variation of soil inorganic nitrogen content. The results showed that the yield was increased by 6. 62% ~ 12. 57%by applying N fertilizer when the dressing ratio is 1∶ 3∶ 2 with base fertilizer N∶ greening N∶ jointing N,and grain yield and protein yield of winter wheat were significantly promoted by nitrogen amount increasing,but they were not significantly increased under 1∶ 1∶ 1 dressing ratio. While the nitrogen amount was 120 kg·hm- 2,grain yield and protein yield were promoted with base fertilizer increasing.While the nitrogen amount was 180 kg·hm- 2,the protein yield was significantly promoted with dressing fertilizer increasing,but the grain yield was not significantly changed. The nitrogen accumulationamount in plant of winter wheat was increased with nitrogen fertilizer amount increasing. With dressing fertilizer increasing,it was declined before reviving stage,but increased after reviving stage. While the nitrogen amount was 120 kg·hm- 2,soil inorganic nitrogen content in plough layer was decreased continuously during the whole growth stage of winter wheat. The soil inorganic nitrogen balance was maintained by nitrogen amount of 180 kg·hm- 2and dressing ratio of 1∶ 3∶ 2. Based on an integrated analysis of grain yield,protein yield and soil inorganic nitrogen balance,nitrogen amount of 180 kg·hm- 2with 1∶ 3∶ 2 dressing ratio was the optimal nitrogen fertilizer application in this region.