不同施氮水平及氮钾配比对玉米产量及氮素积累和利用效率的影响

为探究山西中部地区耐密性玉米品种最佳施氮水平及氮钾配比,以提高玉米产量和品质,制定了优化配方施肥方案,试验选用当地大面积种植的3种耐密性玉米先玉335、郑单958及大丰30,设置200 kg·hm-2、300 kg·hm-2、350 kg·hm-23个施氮量水平,并设1∶1.0、1∶1.5、1∶2.0和1:3.0的氮钾施用配比,分设对照,在成熟期对植株及籽粒含氮量、各处理产量进行测定分析。结果表明:3种供试玉米品种均在施氮量为350kg·hm-2时,达到高产。先玉335和大丰30,在氮钾比为1∶1.5时,玉米单产进一步显著增加,分别达13 773.0 kg·hm-2、14 434.5 kg·hm-2,增产幅度分别达到37.97%和37.10%,同时氮肥利用率分别提升到11.54%和10.02%。郑单958在氮钾比为1∶2.0时,玉米单产极显著提高,达13 464.0 kg·hm-2,增产幅度达40.62%,同时氮肥利用效率提高到12.04%。先玉335以及大丰30整体对氮肥施用水平变化的敏感程度高于郑单958。

The Influence of Different Nitrogen Level and Nitrogen/Potassium Ratio on Maize Yield and Nitrogen Accumulation and Utilization Efficiency

In order to explore the best nitrogen level and nitrogen/potassium ratio of high-density-tolerance maize variety in central Shanxi for improving the yield and quality of maize, this paper formulates the fertilization scheme with optimum formulation, selects three kinds of high-density-tolerance maize varieties for large-area planting in local place including Xianyu 335, Zhengdan 958 and Dafeng 30, sets three nitrogen levels of 200 kg· hm-2, 300 kg· hm-2 and 350 kg· hm-2, and sets four nitrogen/potassium ratios of 1：1.0, 1：1.5, 1：2.0and 1：3.0, and sets up the matched groups respectively, and makes the determination and analysis of the plant and grain nitrogen contents, and the maize yield with different treatments in the mature period. The results show that the three tested maize varieties has achieved high yield at the nitrogen level of 350 kg-hm-2, the per unit yield of Xianyu 335 and Dafeng 30 has further increased significantly at the nitrogen/potassium ratio of 1：2.0, achieving 13 773.0 kg·hm-2 andl4 434.5 kg·hm-2 respectively with the yield rate of 37.97% and 37.10% respectively, and the nitrogen utilization efficiency has increase to 11.54% and 10.02% respectively; the improvement of per unit yield of Zhengdan 958 is highly significant to reach 13 464.0 kg＇ hm-2 at the nitrogen/potassium ratio of 1：2.0 and with the yield rate of 40.62% ,and the nitrogen utilization efficiency has increase to 12.04%; the sensitivity of Xianvu 335 and Dafeng 30 to the ehane of nitrogen level is higher than that of Zhengdan 958.