氮肥施用对水稻干物质积累量产量和氮肥利用率的影响

Effects of Nitrogen Fertilizer Application on Dry Matter Accumulation Yield and Nitrogen Use Efficiency of Rice

以最高施氮量225 kg/hm^(2)为基础依次递减,共设计4个施氮水平,于2022年4月-9月在贵州省黎平县中潮镇上黄村开展氮肥减量施用对水稻干物质积累量、产量和氮肥利用率的影响研究。结果表明:不同施氮处理下水稻生长季干物质积累量变幅在2.38~18.07 t/hm^(2)。其中,在施氮量150 kg/hm^(2)时干物质累积量最大,为18.07 t/hm^(2)。不同氮肥施用量下水稻有效穗数、穗粒数、千粒质量和产量均随着施氮量增加表现为先上升后下降的趋势,在施氮量150 kg/hm^(2)时取得最大值,同时氮素吸收利用率等指标也较施氮量225 kg/hm^(2)有较大提升。

Based on the maximum nitrogen application rate of 225 kg/hm^(2),four nitrogen application levels were designed to study the effects of nitrogen reduction application on rice dry matter accumulation,yield and nitrogen utilization rate from April to September 2022 in Huangcun Village.The results showed that the variation of dry matter accumulation in the growing season of rice under different nitrogen application treatments ranged from 2.38 to 18.07 t/hm^(2),and the maximum value was reached at the mature stage.The maximum dry matter accumulation was 18.07 t/hm^(2) when the nitrogen application rate was 150 kg/hm^(2).The effective panicle number,grain number per panicle,thousand grain mass and yield of rice increased first and then decreased with the increase of nitrogen application rate,and reached the maximum value at the 150 kg/hm^(2) nitrogen application rate.Meanwhile,the indexes of nitrogen absorption and utilization rate also increased significantly compared with the 225 kg/hm^(2) nitrogen application rate.