春季单次灌水对冬小麦产量构成的影响

以冀麦38为试验材料，进行春季田间不同时期单次灌水试验，以研究小麦不同穗发育时期定量灌溉对产量构成因素的影响。结果表明，单次灌水可以协调产量形成的源库关系，雌雄蕊分化期灌溉。单位面积粒数最多，干粒重最低，形成源大库小的群体；抽穗期灌溉，单位面积粒数最少，千粒重最高，形成源小库大的群体；四分体时期灌溉，两者平衡配置比较理想，产量与其他处理相比较高。小麦产量构成因素中，单位面积粒数和干粒重成反比，雌雄蕊分化期充足的土壤水分，扩库作用最强，单位面积担数最多；雌雄蕊分化期后。水分的扩库作用遥渐减弱，增源作用逐渐变强，以抽穗期灌水的增源作用最明显。

Effect of Single Irrigation on Yield Component of Winter Wheat

The impacts of single irrigation at different stage on wheat yield components were studied. Resuits indicate that single irrigation at different stage has different contribution to wheat yield components. Irrigation at floret differentiation stage can increase the number of ears greatly, irrigation at quadrant stage significantly enhanced grains number per ear. Irrigation at heading stage increased 1000 grain weight. 1000 grain weight was the key factor determinirig yield under water saving cultivation, the next was the number of grains per unit area. Sink was enlarged and the total grain number of population was increased by irrigation at pistil-stamen differentiation stage. Irrigated after pistil-stamen differentiation stage, the effect of enlarging sink is reduced gradually and the contribution of strengthening source is increased. The irrigation at heading stage has the most grain number of population. Population was with small source and big sink while irrigation is at pistil-stamen differentiation stage and with big source and small sink while irrigation is at heading stage. The relationship of source and sink has relative good balance while irrigation at quadrant stage with highest level of grain yield.