氮肥运筹对棉花干物质积累、氮素吸收利用和产量的影响

Effect of nitrogen fertilizer management on the dry matter accumulation,N uptake and utilization and yield in cotton

通过膜下滴灌田间试验,研究不同氮肥运筹模式对棉花干物质积累、氮素吸收利用及产量的影响。结果表明,各处理棉花干物质及氮素积累均符合Logistic方程;棉花干物质积累最快时期出现在出苗后83～139 d。不同的氮肥运筹可明显影响棉花氮素吸收最大速率及其出现时间,以有机无机氮肥配施(N2+M)处理的氮素吸收最大速率较高,且其出现时间相对较早。棉株对干物质分配中心与氮素吸收分配中心一致。各施氮处理氮肥利用率在32.11%～49.24%之间,N2+M处理氮肥利用率最高,其它处理氮肥利用率随施氮量的增加而降低。本试验中,N2+M处理产量达1890 kg/hm2,显著高于其它处理。

The effects of different nitrogen fertilizer managements on the accumulation of cotton dry matter,N uptake and utilization and yield were studied under field experiment with drip irrigation.The results showed that the cotton dry matter and nitrogen accumulation fit the Logistic equation.The fastest dry matter accumulation period occurred in 83-139 d after seeding stage.Different managements of nitrogen fertilizer significantly influenced the maximum N uptake rate and present time.Combine application of organic and inorganic N fertilizer（N2＋M） resulted in the maximum N uptake rate and earlier present time.The dry matter distributing center was consistent with that of nitrogen uptake.The nitrogen fertilizer use efficiency was ranged between 32.11% and 49.24% and the highest N utilization rate was found under the treatment N2＋M.Nitrogen use efficiency increased with the reduction of nitrogen application rate.In this experiment,treatment N2＋M had the largest yield 1890 kg/ha,which was significantly higher than the others.