氮肥用量对稻田迟直播油菜产量、效益及氮素吸收和利用的影响

Effects of Nitrogen Application Rate on Yield,Profit and Nitrogen Absorption and Utilization of Rapeseed under Delayed Sowing Condition in Jiangxi Province

以＂赣油杂5号＂为试验材料,通过大田试验研究氮肥用量对江西双季稻区迟直播油菜产量、效益、花后干物质转移及氮肥吸收和利用的影响。结果表明：与对照（不施氮）相比,施氮显著提高了油菜产量和效益,增产幅度在49.65%~66.75%,效益增幅达50%以上,但当施氮量高于180 kg/hm2,增施氮肥的增产效应不显著,经济效益、干物质转移效率和转移干物质对籽粒的贡献率则明显降低;N150处理与N90和N120处理间氮肥农学利用率（ANUE）差异均未达到显著水平,N150与N180、N210和N240处理间氮肥农学利用率（ANUE）差异达到显著水平,且显著高于N180、N210和N240处理。因此,为达到同步实现油菜高产和氮肥高效利用,较好地协调油菜高效生产与氮肥合理利用的统一,江西双季稻区迟直播油菜生产适宜施氮量为150~180 kg/hm2。

Field experiments were carried out to study the effects of nitrogen （N） application rate on rape- seed yield,post-anthesis dry matter translocation and N fertilizer use efficiency under delayed sowing condition in its yield-increasing effect was not significant, its profits, dry matter translocation efficiency and contribution of dry matter transloeation amount to grain decreased significantly.The agronomic nitrogen use efficiency（ANUE） did not reach 0.05 level in N150, N120 and N90 treatments, but the agronomic nitrogen use efficiency（ANUE） reached 0.05 lever between N150 and N180 ,N210 and N240 treatment, the agronomic nitrogen use efficiency （ANUE） iri N150 treatment was significantly higher than that in N180,N210 and N240 treatments.Based on rapeseed yield, profit and nitrogen use efficiency, the optimum N fertilizer application rate was 150-180 kg/hm2 under delayed sowing condition in Jiangxi Province.