中国农业科学 ›› 2021, Vol. 54 ›› Issue (14): 3065-3076.doi: 10.3864/j.issn.0578-1752.2021.14.012

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

不同降雨年型旱地冬小麦水分利用及产量对施氮量的响应

刘朋召(),周栋,郭星宇,于琦,张元红,李昊昱,张琦,王旭敏,王小利,王瑞,李军()   

  1. 西北农林科技大学农学院,陕西杨凌 712100
  • 收稿日期:2020-08-27 接受日期:2020-10-14 出版日期:2021-07-16 发布日期:2021-07-26
  • 通讯作者: 李军
  • 作者简介:刘朋召,E-mail: liupz0819@foxmail.com
  • 基金资助:
    国家科技支撑计划(2015BAD22B02);国家自然科学基金(31801300)

Response of Water Use and Yield of Dryland Winter Wheat to Nitrogen Application Under Different Rainfall Patterns

LIU PengZhao(),ZHOU Dong,GUO XingYu,YU Qi,ZHANG YuanHong,LI HaoYu,ZHANG Qi,WANG XuMin,WANG XiaoLi,WANG Rui,LI Jun()   

  1. College of Agronomy, Northwest A&F University, Yangling 712100, Shaanxi
  • Received:2020-08-27 Accepted:2020-10-14 Online:2021-07-16 Published:2021-07-26
  • Contact: Jun LI

摘要:

【目的】降雨和施氮是影响渭北旱塬冬小麦生产的主要因素,降雨年际变幅大对其影响更大,因此小麦增产效应受降雨年型显著影响。分析不同降雨年型下施氮量对旱地麦田水分利用、籽粒产量和蛋白质含量的影响,能够为实现渭北旱地冬小麦 “因雨施氮”和稳产优质提供理论依据。【方法】于2017—2020年连续3年在陕西合阳县开展田间定位施氮试验,以晋麦47为试验材料,设置5个施氮量处理0、60、120、180、240 kg·hm-2(分别以N0、N60、N120、N180、N240表示),研究不同降雨年型施氮量对冬小麦生育期0—200 cm土层水分变化动态、水分利用效率、产量构成及蛋白质含量的影响。【结果】降雨年型和施氮对冬小麦播前底墒及生育期土壤含水量、耗水量、水分利用效率、籽粒产量和蛋白质含量影响显著。(1)休闲期降雨与播前底墒呈线性相关,每增加1 mm夏季降雨,底墒增加0.9 mm。在丰水年和平水年休闲期降雨充足,前季小麦增加施氮量对下季小麦播前底墒无显著影响;在欠水年休闲期降雨较少,前季小麦每增施氮100 kg·hm-2,下季小麦播前底墒减少15.4 mm。丰水年较欠水年和平水年均能提高冬小麦生育期0—200 cm土层土壤含水量,因而分别增加生育期耗水量35.7%和6.6%。全生育期0—120 cm土层土壤含水量受降雨和冬小麦生长发育影响波动较大,但160—200 cm 深层土壤含水量相对稳定。丰水年的水分利用效率较欠水年和平水年分别提高55.7%和26.5%,籽粒产量分别提高112.3%和39.1%,蛋白质含量分别降低8.3%和5.2%。(2)与N0处理相比,丰水年、欠水年和平水年施氮均降低各生育时期0—200 cm土层土壤含水量,分别提高生育期耗水量4.6%—14.6%、6.0%—8.6%、2.2%—9.5%,分别增加水分利用效率20.7%—39.8%、4.7%—33.3%、13.1%—35.4%,分别增产7.1%—28.1%、1.5%—34.1%、8.5%—28.9%,分别提高蛋白质含量5.6%—10.4%、10.1%—17.7%、8.5%—15.6%。(3)施氮量和籽粒产量、蛋白质产量均符合二次曲线关系,拟合方程表明,丰水年、欠水年和平水年满足旱地冬小麦稳产优质的最适施氮量范围分别为189—202、116—124和161—174 kg·hm-2。【结论】综合来看,丰水年、欠水年和平水年的最佳施氮量分别为189—202、116—124和161—174 kg·hm-2,并可采取“播前底墒确定基施氮肥量+播种至拔节期降雨确定追施氮肥量”的“因雨施氮”管理模式,既能满足旱地冬小麦稳产优质,也可保证水分高效利用。

关键词: 旱地小麦, 降雨年型, 施氮量, 水分利用, 产量

Abstract:

【Objective】Rainfall and nitrogen application are the main factors affecting winter wheat production in Weibei dryland, especially the interannual variability of rainfall is large. Therefore, their yield-increasing effects are significantly affected by the type of rainfall year. In this study, the effects of nitrogen rates on water use, grain yield and protein content in dryland wheat field under different rainfall patterns were analyzed, which provided a theoretical basis for “nitrogen applying according to rain” and ensuring stable yield and high quality of winter wheat in Weibei Dryland.【Method】A 3-year field experiment (2017-2020) of winter wheat (Jinmai 47) was performed with different nitrogen fertilization at five levels (0, 60, 120, 180 and 240 kg·hm-2, represented as N0, N60, N120, N180, and N240, respectively) in Heyang County, located in Weibei dryland of Shaanxi, and the effects of nitrogen application under different rainfall patterns on soil water dynamics, water use efficiency (WUE), wheat yield performance and grain protein content were evaluated. 【Result】Different rainfall patterns had significant impacts on soil water storage before sowing (SWSS), soil water content during growth period, ET, WUE, yield and protein content of winter wheat. (1) There was a linear correlation between rainfall in fallow period (from July to September) and SWSS, with an increment of 0.9 mm SWSS per 1 mm rainfall. In the humid and normal years with adequate rainfall during fallow stage, the SWSs in present winter wheat growth season was not significantly influenced by the increase of nitrogen fertilization in previous growth season. However, in the dry year with less rainfall in fallow stage, the SWSS in present winter wheat growth season decreased significantly by 15.4 mm when nitrogen fertilization in previous growth season was increased by each 100 kg·hm-2. Compared with dry and normal year, the soil water content of 0-200 cm soil layer during growth period of winter wheat could be increased in humid rainfall year, thus evapotranspiration (ET) was increased by 35.7% and 6.6%, respectively. The soil water accumulation of 0-120 cm soil depth during the growth period fluctuated greatly under the influence of rainfall and the growth of winter wheat. However, the soil water content in 160-200 cm deep soil depth showed a stable change trend. Compared with dry and normal year, the WUE in humid pattern was increased by 55.7% and 26.5%, the grain yield was increased by 112.3% and 39.1%, and protein content (PC) was decreased by 8.3% and 5.2%, respectively. (2) Compared with N0 treatment, soil water content in 0-200 cm soil depth was decreased by nitrogen applied during each growth period under humid, dry and normal years. The nitrogen fertilizer application increased ET by 4.6%-14.6%, 6.0%-8.6% and 2.2%-9.5%, increased WUE by 20.7%-39.8%, 4.7%-33.3%, 13.1%-35.4%, increased yield by 7.1%-28.1%, 1.5%-34.1%, 8.5%-28.9%, and increased PC by 5.6%-10.4%, 10.1%-17.7% and 8.5%-15.6%, respectively. (3) The effects of nitrogen rates on grain yield and protein yield followed a quadratic curve relationship, and the fitting equation showed that the optimal nitrogen application rates for stable yield and quality of winter wheat were 189-202, 116-124 and 161-174 kg·hm-2 in humid, dry and normal years, respectively. 【Conclusion】On the whole, the best nitrogen application schemes were 189-202, 116-124 and 161-174 kg·hm-2 in humid, dry and normal years, respectively. And the management model of “nitrogen applying according to rain” was adopted, which was “the amount of basic nitrogen fertilizer was determined by SWSs, while the top dressing of nitrogen fertilizer was determined by rainfall from sowing to jointing stage”. The model could not only meet the requirements of stable yield and high quality of winter wheat, but also ensure water high-efficient use.

Key words: dryland wheat, rainfall patterns, nitrogen fertilizer, water use, yield