丹江口库区玉米和水稻氮合理用量研究

Studies on Rational Nitrogen Application Rates for Corn and Rice in Danjiangkou Reservoir Area

采用田间小区试验研究了丹江口库区玉米和水稻的氮合理用量。结果表明,在施用90kg/hm2P2O5和135.0kg/hm2K2O基础上,玉米最高产量施氮量和最佳经济施氮量分别为276.4kg/hm2和236.2kg/hm2;在施用90.0kg/hm2P2O5、75.0kg/hm2K2O和3.0kg/hm2大粒锌基础上,水稻最高产量施氮量和最佳经济施氮量分别为213.8kg/hm2和189.6kg/hm2;当玉米施氮量为225.0kg/hm2时,比不施氮增产35.8%,氮肥产投比、农学效率和表观利用率分别为4.90、11.4kg/kg和29.9%,玉米氮吸收总量为174.9kg/hm2,养分吸收量之比为N∶P2O5∶K2O=1.00∶0.51∶1.01;当水稻施氮量为180.0kg/hm2时,比不施氮增产28.5%,氮肥产投比、农学效率和表观利用率分别为5.67、12.1kg/kg和39.1%,水稻氮吸收总量为156.1kg/hm2,养分吸收量之比为N∶P2O5∶K2O=1.00∶0.34∶1.20。

Rational nitrogen（N） fertilizer application rates for corn and rice in Danjiangkou reservoir area were studied by field trials.Results showed that on the basis of 90.0 kg/hm^2 P2O5 and 135.0 kg/hm^2 K2O,the N fertilizer application rates on corn for highest yield and the optimum economic yield were 276.4 kg/hm^2 and 236.2 kg/hm^2 respectively.On the basis of 90 kg/hm^2 P2O5,75.0 kg/hm^2 K2O and 3.0 kg/hm^2 ZnSO4·7H2O,the N fertilizer application rates on rice for highest yield and the optimum economic yield were 213.8 kg/hm^2 and 189.6 kg/hm^2 respectively.With N fertilizer application rate of 225.0 kg/hm^2,corn yield increased by 35.8% compared with CK,and the VCR,agronomic efficiency and apparent N recovery by corn of N fertilizer were 4.90,11.4kg/kg and 29.9% respectively.The total N uptake by corn plant was 174.9 kg/hm^2,and the nutrients uptake ratio by corn was N∶P2O5∶K2O=1.00∶0.51∶1.01.With N fertilizer application rate of 180.0 kg/hm^2,rice yield increased by 28.5% compared with CK,and the VCR,agronomic efficiency and apparent N recovery by rice of N fertilizer were 5.67,12.1 kg/kg and 39.1% respectively.The total N uptake by rice plant was 156.1 kg/hm^2,and the nutrients uptake ratio by rice was N∶P2O5∶K2O=1.00∶0.34∶1.20.