氮肥深施对水稻生长和产量的影响

目的]为氮肥在巢湖流域水稻生产中的合理施用提供参考。方法]试验设全程深施、基肥深施、面施和不施氮肥4个处理，采用完全随机排列研究了氮肥深施对水稻生长和产量的影响。结果]拔节期和抽穗期，不同处理的根冠比和根系干重的大小关系为：全程深施〉基肥深施〉面施。成熟期，不同处理的根冠比和根系干重的大小关系为：全程深施〉面施〉基肥深施。与不施氮肥处理相比．面施、基肥深施和全程深施处理的单位面积有效穗数分别提高了39．9％、40．5％和39．4％，每穗粒数分别增加了5．1％、5．7％和10．3％。与面施处理相比，基肥深施和全程深施处理的每穗粒数分别增加了0．6％和5．8％；全程深施处理的千粒重增加了5．5％。施氮处理较不施氮处理增产43．0％～52．5％，全程深施处理较面施处理增产6．7％。结论]氮肥深施可以促进水稻的生长发育，提高水稻的产量。

Effect of the Deep Application of N Fertilizer on the Growth and Yield of Rice

Objective] The study aimed to supply references for the reasonable application of N fertilizer in the rice production of Chaohu Lake basin. Method] Four treatments of full-process deep application, deep application of base fertilizer, superficial application and no N application were arranged in the experiment and the completely random arrangement was adopted to study the effects of the deep application of N fertilizer on the growth and yield of rice. Result] In jointing and heading stages, the sequence of root-shoot ratios and dry root weights of different treatments was as follow; full-process deep application > deep application of base fertilizer > superficial application. In maturing stage, the sequence of root-shoot ratios and dry root weights of different treatments was as follow: full-process deep application > superficial application > deep application of base fertilizer. Compared with no N application treatment, the effective panicles per unit area in the treatments of superficial application, deep application of base fertilizer and full-process deep application were increased by 39. 9% , 40. 5% and 39.4% resp. and their grains per panicle were increased by 5. 1 % , 5. 7% and 10. 3% resp. Compared with the treatment of superficial application , the grains per panicle in the treatments of deep application of base fertilizer and full-process deep application were increased by 0.6% and 5. 8% resp. and the 1 000-seed weight in the treatment of full-process deep application was increased by 5. 5%. Compared with no N application treatment, the yields were increased by 43.0% -52.5% in N application treatments. Compared with the treatment of superficial application , the yield in the treatment of full-process deep application was increased by 6.7%. Conclusion ] The deep application of N fertilizer could promote the growth and development of rice and increase its yield.