不同生育期干旱对冬小麦产量及水分利用效率的影响

用盆栽对冬小麦不同生育阶段进行不同程度水分调亏试验结果表明 :拔节—孕穗期、抽穗—扬花期和灌浆—成熟 3个阶段内 RW上限为 4 0 %、5 0 %、60 %的水分亏缺均引起了产量的极显著下降 ,而且水分亏缺越严重 ,产量降低越大。在 3个生育阶段内进行 RW上限为 4 0 %的水分调亏减产幅度都很大 ,而且 3个生育阶段之间差异不明显 ;进行 5 0 %、60 %水分调亏 ,其减产程度则与生育期有关。灌浆—成熟期的减产程度大于前二个时期 ,这可能与前二个阶段复水后作物的补偿生长有关。不同生育期水分亏缺对冬小麦产量构成因素的影响也不同 ,拔节—扬花期水分亏缺主要减少了穗粒数 ,灌浆—成熟阶段的水分亏缺主要减少了千粒重

Effects of Water Deficits on Yield and WUE in Winter Wheat

An Experiment was conducted to study the effects of water deficits in different growing stages to plant growth, development and yield in winter wheat. Results show that water deficits decreased grain yield obviously. The more serious the stress was, the greater the yield decreased. In three stages (Jointing to booting, heading to flowering, and grain filling to harvest), yield loss was the greatest in treatment W1(upper limit of RW was set as 40%). But the effects of water stress on yield was different in different growing states in treatment W2 and W3(Upper limits of RW was set as 50% and 60% respectively). The yield loss was larger in period of grain filling to harvest than those in other two periods. Effects of water deficits in different stages on yield components were different also. Drought occurred in period from jointing to flowering lowered grain number mainly, and drought in grain filling stage decreased grain weight mainly.