摘要：

为探究拔节期灌溉和追施氮肥对旱地沟播小麦籽粒产量、品质和氮素积累转运的影响,2019年10月至2020年6月,在沟播种植小麦的基础上,于拔节期设置不灌溉不追氮肥(NIND)、全沟灌溉不追氮肥(EFIND)、隔沟灌溉不追氮肥(AFIND)、全沟灌溉追施氮肥(EFITD)、隔沟灌溉追施氮肥(AFITD)5个处理,分析了小麦产量及其构成因素、主要品质指标和地上部氮素积累转运分配特性。结果表明,拔节期灌溉与否、灌溉方式和追施氮肥均可显著调控旱地沟播小麦产量、品质和氮素积累转运特性,且作用效果有叠加效应。与NIND相比,EFIND、AFIND、EFITD、AFITD 的产量分别显著提高46.57%,67.72%,83.71%,95.88%;开花期氮素积累量、花后氮素积累量、花后氮素积累对籽粒氮素的贡献率均显著提高,从而使成熟期氮素积累量分别显著提高25.94%,41.00%,65.86%,82.64%。与NIND相比,EFIND、AFIND和EFITD显著降低小麦品质,而AFITD的品质不降低甚至显著提高。隔沟灌溉较全沟灌溉,开花期氮素积累量无显著差异,花后氮素积累量显著提高,从而使成熟期氮素积累总量和籽粒氮素积累量显著提高,不追施氮肥时产量显著提高,但除沉降值外各品质指标无显著差异,追施氮肥条件下产量和各品质指标均显著改善。追施氮肥与不追氮肥相比,开花期氮素积累量、花前氮素转运量、花后氮素积累量、花后氮素积累对籽粒的贡献率均显著增加,从而使成熟期地上部氮素积累量、籽粒分配比例显著增加,进而使籽粒产量和籽粒氮素积累量显著提高,品质多表现为显著改善,且隔沟灌溉的提质效应较全沟灌溉大。拔节期隔沟灌溉与追施氮肥结合不仅可显著提高开花期和开花后的氮素积累量,而且可显著提高花前氮素向籽粒的转运量,从而显著提高成熟期籽粒氮素积累量和分配比例,最终在提高产量的同时改善品质,是适宜旱地沟播小麦的灌溉施肥方式。

关键词: 小麦, 旱地, 隔沟灌溉, 追施氮肥, 沟播, 产量, 品质

Abstract:

In order to explore the effects of irrigation method and topdressing nitrogen on grain yield,quality and nitrogen accumulation and translocation of furrow-seeding wheat in dryland,a field experiment including five treatments,i.e.no irrigation and no topdressing nitrogen(NIND),every furrow irrigation and no topdressing nitrogen(EFIND),alternative furrow irrigation and no topdressing nitrogen(AFIND),every furrow irrigation and topdressing nitrogen(EFITD)and alternative furrow irrigation and topdressing nitrogen(AFITD),were set at jointing stage based on a no-tillage furrow-seeding wheat field from October 2019 to June 2020.The grain yield and its components,main quality index,as well as the shoot nitrogen accumulation,translocation and distribution were measured.The results showed that irrigation at jointing stage,irrigation mode and topdressing nitrogen significantly regulated the yield,quality and nitrogen accumulation and translocation of furrow-seeding wheat in dryland,and the regulation effects was additive.Compared with NIND,the grain yields in EFIND,AFIND,EFITD and AFITD were significantly increased by 46.57%,67.72%,83.71%,95.88%,as well as the nitrogen accumulation at anthesis,the post-anthesis nitrogen accumulation and its contribution rate to grain were significantly increased,so the nitrogen accumulation amounts at maturity were significantly increased by 25.94%,41.00%,65.86%,82.64%.Compared with NIND,the quality in EFIND,AFIND and EFITD was significantly decreased,while that in AFITD did not decrease or even significantly increased.Compared with EFI,AFI did not affect the nitrogen accumulation at anthesis,but significantly increased the post-anthesis nitrogen accumulation,and thus significantly increased the total nitrogen accumulation at maturity and grain nitrogen accumulation.Finally,compared with EFI,the grain yield in AFI was significantly increased,but the difference of quality indexes except the sedimentation value was not significant under ND,while the significant improvement of grain yield and various quality indexes was observed under TD.Compared with ND,the nitrogen accumulation at anthesis,pre-anthesis nitrogen accumulation and its translocation amount,post-anthesis nitrogen accumulation and its contribution rate to grain in TD were significantly increased,and thus the shoot nitrogen accumulation and grain nitrogen distribution rate at maturity were also significantly increased,so the grain yield,grain nitrogen accumulation and grain quality were significantly improved.Moreover,the regulation effect on quality under AFI was greater than that under EFI.In conclusion, AFITD could not only improve the shoot nitrogen accumulation at anthesis and after anthesis, but also significantly increased the amount of pre-anthesis nitrogen translocation to grain, and the shoot nitrogen accumulation and its distribution rate in grain at maturity, thus finally synergistically improved grain yield and quality of furrow-seeding wheat. Therefore, alternative furrow irrigation combined with topdressing nitrogen at jointing stage could be recommended as an alternative mode in dryland.

Key words: Wheat, Dryland, Alternative furrow irrigation, Topdressing nitrogen, Furrow-seeding, Yield, Quality