耕作方式与灌水次数对砂姜黑土冬小麦水分利用及 籽粒产量的影响

【目的】 探讨耕作方式与灌水次数对砂姜黑土冬小麦水分利用和籽粒产量的影响,明确适宜砂姜黑土区冬小麦产量和水分利用效率同步提高的耕作与灌水处理组合模式。【方法】 于2015—2017年连续2个冬小麦生长季,在豫东南砂姜土区设置旋耕（RT）、深松（SS）2种耕作方式为主处理和拔节期+开花期灌2次水（W2）、拔节期灌1次水（W1）、全生育期不灌水（W0）3种灌水为副处理的二因素裂区试验,深入研究耕作方式与灌水次数的主效应及其互作效应对砂姜黑土冬小麦水分利用和籽粒产量的影响。【结果】 耕作与灌水对砂姜黑土麦田耗水特性、水分利用效率及籽粒产量均具有明显的调控效应。SS较RT处理可显著增加土壤贮水消耗,有利于提高自然降水和灌溉水的利用效率,与RT相比,两年度SS处理的土壤平均贮水消耗量、降水、灌水利用效率分别提高13.69%、7.03%、6.51%;增加灌溉虽可明显增加冬小麦田间耗水量,但过多灌溉致使水分利用效率降低,两年度W2较W1、W0的水分利用效率平均值分别下降18.85%、16.69%。SS处理的籽粒产量显著高于RT处理,且以深松+拔节期灌1水处理组合SSW1的产量最高。相同耕作方式下,随灌水次数的增加,千粒重呈降低趋势,成穗数呈增加趋势;两年度穗粒数变化总体随灌水次数的增加呈先升后降的变化规律。耕作方式主要通过调控千粒重影响产量,灌水次数则主要通过调控穗粒数和千粒重而影响产量,但灌水过多会抑制穗粒数和千粒重的提高。【结论】 综合考虑耕作方式与灌水次数对冬小麦水分利用和籽粒产量的调控效应,深松+拔节期灌1水处理组合SSW1可作为适宜豫东南砂姜黑土区冬小麦产量和水分利用效率同步提高的耕作与灌水处理组合模式。

Effects of Tillage Practices and Irrigation Times on Water Use Efficiency and Grain Yield of Winter Wheat in Lime Concretion Black Soil

【Objective】This research was conducted to explore the effects of tillage practices and irrigation times on water use efficiency and grain yield of winter wheat in lime concretion black soil, and to identify an optimal tillage and irrigation combination mode of winter wheat in lime concretion black soil with high yield and water use efficiency simultaneously. 【Method】The two-factor split plot experiment was persistently performed in the lime concretion black soil in the southeast area of Henan province during two continuous winter wheat growing seasons (2015-2017). In this experiment, the two tillage practice treatments, including rotary tillage (RT) and subsoiling (SS), were set as the main treatment. The three soil moisture treatments, including twice irrigation at jointing and anthesis, once irrigation at jointing, no irrigation, expressed as W2, W1, W0, respectively, were set as secondary treatment, deeply exploring the effects of tillage practices and irrigation times and their interaction effects on water use efficiency and grain yield of winter wheat in lime concretion black soil. 【Result】 Tillage and irrigation had obvious regulation effects on water consumption characteristics, water use efficiency and grain yield of wheat in lime concretion black soil. Compared with RT, SS could significantly increase soil water storage consumption, which was beneficial to increase the utilization efficiency of precipitation and irrigation water, and the soil water storage consumption, precipitation and irrigation water use efficiency increased by 13.69%, 7.03%, 6.51% in two-year degrees, respectively. Although increasing irrigation could significantly promote water consumption in winter wheat fields, excessive irrigation resulted in lower water use efficiency. Compared with W1 and W0, the average soil water storage consumption and water use efficiency of W2 decreased by 18.85% and 16.69% in two-year degrees, respectively. The grain yield of SS treatment was significantly higher than that of RT treatment and the yield of the combination treatment subsoiling, and once irrigation at jointing (SSW1) was the highest. Under the same tillage practice, the 1000-grain weight decreased and the number of grains per spike increased with the increase of irrigation times. The variation of grain number per spike in the two years increased firstly and then decreased with the increase of irrigation times. The tillage practice mainly affected the final yield by regulating 1000-grain weight and the irrigation times mainly affected the yield by regulating the grain number per spike and 1000-grain weight, but excessive irrigation would resist the increase of grain number and 1000-grain weight. 【Conclusion】Based on the regulating effects of tillage practices and irrigation times on water use efficiency and grain yield, the SSW1 treatment could help synchronously to improve the grain yield and water use efficiency. This can be an optimal model of tillage and irrigation combination treatment of winter wheat in lime concretion black soil area of southeast Henan province.