控释氮肥适量减施对玉米产量和氮素利用效率的影响

Reducing Application of Controlled-release Nitrogen Fertilizer to Improve Maize Yield and Nitrogen Utilization Rate

通过连续两年田间试验,研究控释氮肥较农民习惯用量减施对玉米产量与产量构成因素、氮素吸收利用的影响。试验设5个处理,分别为不施氮肥(N0)、农民习惯施氮(FP)、80%控释氮肥(CRU1)、70%控释氮肥(CRU2)、60%控释氮肥(CRU3)。结果表明,与FP处理相比,CRU1和CRU2处理显著提高了玉米产量(P<0.05),两年平均产量分别提高7.0%和5.4%。CRU1、CRU2处理两年平均玉米氮素最大积累速率和平均积累速率较FP处理分别提高9.6%、6.5%和7.9%、6.2%,玉米氮素最大增长速率出现天数分别提前7.2 d、5.0 d。与FP处理相比,控释氮肥减量施用处理显著提高了氮素回收率、农学利用率和偏生产力(P<0.05),其中,氮素回收率和偏生产力随控释氮肥减施比例的增加显著增加,氮素农学利用率表现为先增后降,以CRU2处理最高。控释氮肥减量30%(193 kg/hm^(2))可实现玉米产量和氮素利用率同步提高。

Two-year field experiment was conducted to investigate the effects of reduced application of controlled-release N fertilizer(CRU)compared with farmer conventional fertilization on maize yield,its components,N absorption and utilization.The experiment was set up five treatments,including no N fertilizer(N0),farmer conventional fertilization(FP),80%CRU(CRU1),70%CRU(CRU2),and 60%CRU(CRU3).The results showed that CRU1 and CRU2 treatments increased significantly maize yield(P<0.05)than FP treatment.The two-year average yield increased by 7.0%and 5.4%,respectively.The maximum and average N accumulation rates of maize under CRU1 and CRU2 treatments were increased by 9.6%,6.5%and 7.9%,6.2%than FP treatment,and the days of maximum N increase rate appeared 7.2 d and 5.0 d earlier,respectively.Compared with FP treatment,reduced application of CRU significantly improved REN,AEN,and PFPN(P<0.05).REN and PFPN significantly increased with increasing of the reduction ratio of CRU.While AEN increased at first and decreased later,and the highest value was found under CRU2 treatment.30%reduction of CRU(193 kg/ha)can achieve simultaneous improvement of maize yield and N use efficiency in this condition.