施氮量和底追比例对小麦氮素吸收转运及产量的影响

Effects of Nitrogen Rate and Ratio of Base Fertilizer and Topdressing on Uptake,Translocation of Nitrogen and Yield in Wheat

应用15N示踪技术研究了高产麦田中施氮量和底施与追施氮肥的比例对小麦氮素吸收转运及籽粒产量的影响。共设7个处理,对照为不施氮肥(N0);在施纯氮量为168和240kg/hm2条件下,各设底肥氮量与追肥氮量比例(底追比例)为1∶1(N1和N4)、1∶2(N2和N5)、0∶1(N3和N6)。结果表明,播种至拔节期植株积累的底施氮占植株全生育期积累底施氮总量的78.04%～89.67%;小麦植株对追肥氮的利用率显著高于对底肥氮的利用率,适当增加追施氮肥的比例可提高氮肥利用率,其中N2处理的最高。在相同底追比例下,不同施氮量处理相比较,植株与籽粒中的氮素积累量均无显著差异;施氮量相同,随追施氮肥比例的增加,开花前贮存氮素的转运量和转运效率呈先增加后降低的趋势,N2和N5的转运量及转运效率最高;开花后氮素的同化量及对籽粒的贡献率则随追施氮比例的增加而提高;籽粒氮素积累量在N2、N3、N5和N6处理间无显著差异,但显著高于N1和N4。适量施氮并增加追施氮肥的比例可显著提高籽粒产量、蛋白质含量,N2、N5和N6均效果较好。在本试验条件下,施氮量为168kg/hm2及底追比例为1∶2的处理是兼顾产量、品质和效益的最佳氮肥运筹方式。

Application of nitrogen(N)fertilizer is one of the most important measures to increase grain yield and protein content in winter wheat(Triticum aestivum L.)production.However,misuse of N fertilizer will not only affect grain yield and quality,but also cause the decline of economic effects and related environmental effects.It is essential to study reasonable nitrogen applying regimes for profitable yields,efficient N utilization,and reduction of possible environment pollution.The objectives of this study wer...