水分处理对冬小麦生育期耗水分配及产量影响

Impact of Irrigation Schedules on Yield, Water Consumption and Water Use Efficiency of Winter Wheat

【目的】探索冬小麦产量及水分利用效率对灌溉水在生育期运筹的响应过程。【方法】通过人工控水试验开展了6个生长季(2012—2018年)的测坑冬小麦灌溉试验,试验设置不同灌溉水时间和不同次灌水定额,3个处理分别为拔节90 mm(I90)、拔节45 mm+抽穗45 mm(I45*2)、拔节30 mm+抽穗30 mm+灌浆30 mm(I30*3),总灌溉额均为90 mm,重点研究了灌溉水在生育期分配对冬小麦产量和水分利用效率(WUE)的影响。【结果】6个生长季的试验数据统计分析表明,I90、I45*2和I30*3处理的平均产量分别为6 878.3、7 249.1和7 568.6 kg/hm^2;与I90处理相比,I45*2和I30*3处理的产量分别提高了4.4%和10.0%;在灌溉定额一定条件下,不同灌溉处理对生育期总耗水没有显著影响,但I45*2处理比I90处理生殖生长阶段的耗水增加了23.7%,且生育期水分利用效率提高了14.8%。【结论】有限供水条件下,小定额多次灌溉可以有效改善生育后期麦田水分状况,有利于光合产物向籽粒的转化,进一步提高冬小麦千粒质量和收获指数,最终提高了冬小麦经济产量和水分利用效率。

【Objective】With freshwater in Hebei Plain becoming scarcer, limiting groundwater extraction for agricultural irrigation has been mandated. Optimizing irrigation schedule of winter wheat using limited water becomes essential to maximizing crop yield to safeguard food production in this region. The overarching objective of this paper is to investigate the impact of irrigation schedule on water consumption and use efficiency of winter wheat during vegetative-production stage, as well as the ultimate yield.【Method】A six-year experiment(2012-2018) was conducted in a field plot by limiting the overall irrigation amount to 90 mm. We compared four irrigation frequencies: irrigating all water at the jointing stage(I90), irrigating at the jointing and anthesis stage each with 45 mm of water(I45*2), irrigating at jointing, heading and earlier grain-filling stage each with 30 mm of water(I30*3). For each treatment, we measured water consumption at different growing stages and the final yield.【Result】Increasing irrigation frequency improved water use by the crop during productive stage, benefiting harvest index(HI) and grain weight. The average yield over the six years under treatments I90, I45*2 and I30*3 was6 878.3, 7 249.1 and 7 568.6 kg/hm^2, respectively. There was no significant difference in water consumption between the treatments, despite I45*2 improving WUE at reproductive stage by 23.7%, compared to I90.【Conclusion】Optimizing irrigation schedule with limited water to winter wheat is able to minimize yield loss.