有限供水条件下旱地春小麦水分的高效利用(英文)

High Efficient Use of Limited Supplement Water by Dryland Spring Wheat

全球气候变化最令人担忧的问题是干旱 ,而水分又是影响小麦产量的重要因素之一 ,农田水分的管理与有效利用已经受到人们的高度重视。作者以春小麦为实验材料 ,采用盆栽和小区试验相结合的方法 ,针对黄土高原半干旱地区的有限水分环境 ,研究了有限供水的高效利用问题。盆栽条件下 ,采用 3种肥力水平与拔节期、孕穗期和灌浆期有限供水组合处理。对生长发育、产量构成和水分利用效率等指标测定的结果表明 ,施肥可以显著增大叶面积 ,促进根系生长 ,提高子粒产量 ;而施肥条件下 ,拔节期有限供水能够显著增加穗粒数和粒重。小区试验结果表明 ,满足春小麦最大产量所需的灌水量约为 2 0 0 m m ,获得作物水分利用效率最高时的适宜灌水量约为 10 0 m m ,而拔节期 60 m m的灌水量可以使灌水利用效率接近最大值。拔节期 60 m m灌水条件下 ,耗水量、作物水分利用效率和灌水利用效率同步增长 ,同时土壤的贮存水也得到了有效利用。根据以上结果可得出 :在黄土高原缺水地区 ,春小麦有限灌溉的适宜灌水量下限应不低于 60 m m。

Considering water limited conditions in the semiarid areas of the Loess Plateau, dryland spring wheat was chosen as the research materials, high efficient use of limited irrigation was studied. Under the three levels of fertilizer input and the jointing, heading, grain filling stages of limited water supplement conditions, plant growth, grain yield components and water use efficiency were measured. The results showed that leaf area, root system, and grain yields were promoted significantly by soil fertilization. Under the soil fertilized conditions, limited water supplying at the jointing stage was able to enhance kernel number per ear and kernel mass obviously. The maximum supplementary irrigation water to meet the greatest grain yield of spring wheat was about 200 mm. The suitable supplementary irrigation water to satisfy the highest crop water use efficiency was 100 mm. The limited supplementary irrigation water to meet the optimal irrigated water use efficiency is 60 mm. In the case of 60 mm supplementary irrigation, crop water consumption, water use efficiency and irrigation efficiency were greatly improved synchronously. And also, efficiency of stored soil water used by crop was increased correspondingly. It is concluded that critical quantum of limited irrigation water for dryland spring wheat was not less than 60 mm in the Loess Plateau. Effects of limited irrigation indicated that the best period of limited water supply should be the jointing stage.