稳定氮肥用量对夏玉米产量和氮肥利用率的影响

通过大田小区试验,研究了稳定氮肥不同用量对夏玉米产量、养分累积量、氮肥利用效率及经济效益的影响。结果表明,与不施稳定氮肥相比,稳定氮肥施氮量90、150、210 kg·hm^-2和270 kg·hm^-2分别增产36.7%、62.1%、76.6%和81.9%,地上部氮素总累积量分别增加39.0%、60.3%、79.0%和113.4%,经济效益分别增加36.1%、61.2%、72.7%和77.1%;与农民习惯施用氮肥相比,高量稳定氮肥用量210 kg·hm^-2和270 kg·hm^-2分别增产7.3%和10.5%,地上部氮素总累积量分别增加3.2%和23.0%,经济效益分别增加9.7%和11.4%。施用稳定氮肥促进夏玉米对氮素的吸收累积,高量210 kg·hm^-2和270kg·hm^-2处理较习惯施氮提高总吸氮量。施用稳定氮肥各处理氮肥表观利用率和农学效率显著高于农民习惯施氮,偏生产力高于农民习惯施氮,生理效率除270 kg·hm^-2处理外,高于农民习惯施氮。稳定氮肥施氮量在210 kg·hm^-2时,能较好地协调玉米高产与稳定氮肥合理利用的统一。

Effects of Stabilized Nitrogen Fertilizer on Grain Yield and Nitrogen Use Efficiency of Summer Maize

A summer maize field experiment was carried out in 2013 to investigate the effects of stabilized nitrogen fertilizer rates on yield, nitrogen accumulation, nitrogen efficiency of summer maize, and economic efficiency. Compared with no stabilized nitrogen fertilizer, the yield of stabilized nitrogen fertilizer treatments as 90, 150, 210 N kg·hm^-2 and 270 N kg·hm^-2 increased 36.7%, 62.1%, 76.6%and 81.9%respectively. Total N absorbed by above ground parts increased 39.0%, 60.3%, 79.0%and 113.4%, and economic benefits increased 36.1%, 61.2%, 72.7%and 77.1%respectively. Compared with farmer conventional nitrogen fertilizer practices, the yield of stabilized nitrogen fertil-izer treatments as 210 N kg·hm^-2 and 270 N kg·hm^-2 increased 7.3%and 10.5%respectively. Total N absorbed by above ground parts in-creased 3.2%and 23.0%, and economic benefits increased 9.7%and 11.4%respectively. The results demonstrated that stabilized nitrogen fertilizer application significantly promoted growths yield and N accumulation. 210 N kg·hm^-2 and 270 N kg·hm^-2 increased total nitrogen absorption higher than farmer conventional nitrogen fertilizer practices. Nitrogen apparent recovery efficiency(NARE)and nitrogen agronom-ic efficiency(NAE)of application with stabilized nitrogen fertilizer were significant higher than those of farmer conventional nitrogen fertiliz-er practices. Nitrogen partial factor productivity(NPFP)of applied stabilized nitrogen fertilizer was higher than that of conventional nitrogen fertilizer practices. Nitrogen physiological efficiency(NPE)was higher than that of conventional nitrogen fertilizer practices with exception of 270 N kg·hm^-2. Based on summer corn yield and N use efficiency, the optimum stabilized nitrogen fertilizer application rate was 210 N kg·hm^-2.