不同耕作措施对黄土高原春小麦(Triticum aestivuml)氮素吸收与分配的影响

为了探索不同耕作措施下氮肥利用效率。本研究以春小麦品种‘定西42号’为试验材料进行田间小区试验,设置4个处理:传统耕作覆盖(traditional tillage cover,TS)、免耕(no-tillage,NT)、免耕覆盖(no-tillage cover,NTS)和传统耕作(traditional tillage,T)(CK)的保护性耕作试验,研究不同耕作措施对黄土高原丘陵沟壑区春小麦氮素累积与转运的影响。研究表明:保护性耕作免耕覆盖促进小麦植株对氮素的吸收,TS、NT、NTS处理分别T处理的氮素吸收量增加24.2%、3.9%和58.7%,各处理差异显著(p<0.05)。成熟期春小麦各器官氮素的分配量和分配比例为:子粒>茎杆+叶鞘>叶片>根。NTS处理条件下,其子粒中的氮素分配量最大(152.78 kg/hm^2),与之相比,T、TS、NT处理分别减少了30.4%、12.1%及19.3%,各处理差异显著(p<0.05)。春小麦营养器官中的氮素向子粒的转移量和转移率在开花期之后均以NTS处理最大,分别比T、TS、NT处理显著增加37.0%、8.2%、19.1%和22.4%、5.3%、9.5%,但NTS处理小麦氮素转移量对子粒的贡献率最小(73.04%)。各处理氮肥生产效率和收获指数均呈NTS>TS>NT>T,以NTS处理最高,分别比T处理显著高37.8%、18.7%,各处理差异显著(p<0.05)。因此综合考虑氮素吸收、分配及氮素利用效率等因素,NTS是基于本试验条件下该地区春小麦最佳耕作模式。本研究为黄土高原丘陵沟壑区最佳耕作模式提供科学依据。

Effects of Different Tillage Practices on Nitrogen Absorption and Distribution of Triticum aestivuml in the Loess Plateau

In order to explore the utilization efficiency of nitrogen fertilizer under different tillage measures.In this study,the spring wheat variety’Dingxi No.42’was used as the experimental material for the field plot experiment,and four treatments were set up:traditional tillage cover(TS),no-tillage(NT),no-tillage cover(no-tillage cover,NTS)and traditional tillage Traditional tillage(T)(CK)conservation tillage experiments to study the effects of different tillage measures on nitrogen accumulation and translocation of spring wheat in hilly and gully regions of the Loess Pla teau.The results showed that:Conservation tillage no-tillage increased the nitrogen uptake by wheat plants,and the nitrogen uptake by TS,NT and NTS treatments increased by 24.2%,3.9%and 58.7%,respectively,compared with traditional tillage(T)treatment.Treatment differences were significant(p<0.05).The distribution and distribution ratio of nitrogen in various organs of spring wheat at maturity are:seed>stem+leaf sheath>leaf>root.Under the condition of NTS treatment,the nitrogen distribution in the grain was the largest(152.78 kg/hm^2),compared with 30.4%,12.1%and 19.3%in the treatment of T,TS and NT,respectively,with significant differences in treatment(p<0.05).The transfer amount and transfer rate of nitrogen to the granules in the vegetative organs of spring wheat were treated with NTS after the flowering period.With a significant increase of 37.0%,8.2%,19.1%,22.4%,5.3%,and 9.5%respectively over T,TS,and NT treatments.However,the contribution of NTS to wheat nitrogen transfer was the smallest(73.04%).The production efficiency and harvest index of each treatment nitrogen fertilizer were NTS>TS>NT>T,with the highest treatment with NTS,was significantly higher than T processing by 37.8%and 18.7%,respectively,with significant differences in treatment(p<0.05).Taking into account such factors as nitrogen absorption,distribution,and nitrogen utilization efficiency,NTS is based on the optimal cultivation model of spring wheat in the area under this test condition.This study provides a theoretical basis for the optimal tillage mode in Hilly and gully areas of the Loess Plateau.