种植密度和施氮量对不同株高夏玉米产量和氮素利用的影响

摘要

[目的]本研究旨在探讨不同株高夏玉米产量和氮素利用对种植密度和施氮量的响应.[方法]以矮秆玉米品种登海661 (DH661)、中秆品种郑单958 (ZD958)和高秆品种鲁单981 (LD981)为试验材料,在大田条件下设置2个种植密度(67500和82500 plant/hm2)和3个施氮量(N0、180和270 kg/hm2),以不施氮为对照,研究种植密度和施氮量对不同株高夏玉米氮素吸收与利用特性的影响.[结果]在密度为82500 plant/hm2条件下,品种DH661、ZD958和LD981的籽粒产量分别较67500 plant/hm2分别提高5.0％、10.2％和12.5％;施氮180和270 kg/hm2处理DH661、ZD958和LD981的籽粒产量差异不显著.高密度条件下(82500 plant/hm2),施氮270 kg/hm2时DH661氮素转运效率和转运氮贡献率较180 kg/hm2显著降低,ZD958和LD981变化不显著;低密度条件下(67500 plant/hm2),施氮270 kg/hm2时DH661和ZD958氮素转运效率和氮素转运贡献率较180 kg/hm2显著提高,LD981的则显著降低.DH661的氮素利用效率较ZD958和LD981分别提高7.4％和39.1％,LD981的氮素吸收效率较ZD958和DH661品种分别提高18.9％和25.0％.[结论]在低密度67500 plant/hm2条件下,增施氮肥,矮秆和中秆品种的氮素转运效率和氮素转运贡献率显著降低,而高秆品种的则提高.高密度82500 plant/hm2条件下,增施氮肥,矮秆品种氮素转运效率和氮素转运贡献率显著降低,中秆和高秆品种的无显著变化.%[Objectives] This study is to investigate grain yield,nitrogen uptake and use efficiency of summer maize with different plant height in response to plant density and nitrogen rate.[Methods] Three hybrids:highstalk (Ludan981,LD981),medium-stalk (Zhengdan958,ZD958) and short-stalk (Denghai661,DH661) were used as experimental materials in a field experiment.Two plant densities of 67500 and 82500 plants/hm2,and three nitrogen rate of 0,180 and 270 kg/hm2 were designed for each hybrid.The yield,N contents and accumulation were investigated;the N translocation rate and their contribution to yield were calculated.[Results] The grain yields of three hybrids DH661,ZD958 and LD981 in density of 82500 plants/hm2 were 5.0％,10.2％ and 12.5％ higher than those in density of 67500 plants/hm2,but the differences between N treatment of 180 and 270 kg/hm2 were not significant under the two densities.When the density was 82500 plants/hm2,the nitrogen translocation efficiency (NTE) and nitrogen contribution proportion (NCP) of DH661 in N 270 kg/hm2 were significantly lower than those in N 180 kg/hm2,those of hybrids of ZD958 and LD981 were not varied obviously.When the density was 67500 plants/hm2,the NTE and NCP of DH661 and ZD958 in N 270 kg/hm2 were higher than those in N 180 kg/hm2,but those of LD981 were opposite.Nitrogen use efficiency (NUE) of DH661 was 7.4％ and 39.1％ higher than those of ZD958 and LD981 respectively,and nitrogen uptake efficiency (NUPE) of LD981 was 18.9％ and 25.0％ higher than those of ZD958 and DH661,respectively.[Conclusions] Under density of 67500 plant/hm2,high nitrogen fertilizer input will decrease the nitrogen translocation efficiency and nitrogen contribution of medium and short stalk hybrids but increase those of high stalk hybrid.Under high density of 82500 plant/hm2,high N fertilizer rate will significantly decrease the two items of short hybrid,but not decrease those of medium and high stalk hybrids.