春小麦不同生育期断水对水分利用率的影响

Effect of Break Water off in Different Growth Period on Water Use Efficiency of Spring Wheat

利用盆栽方法研究了不同土壤含水量下不同时期断水对春小麦生长和水分利用率的影响,结果表明:各处理在断水初期蒸散强度明显高于断水后期;随着春小麦生育进程的推进,土壤水分含量各水平梯度断水前日平均耗水量增加,同一梯度土壤水分含量在断水后,到达各临界水分的时间有缩短的趋势;同一断水时间,随着土壤水分含量增加到达各临界水分时的日平均蒸散量也增加;同一水平梯度含水量随断水日期推后水分利用率提高。

By pot experiment,the growth and water use efficiency（WUE） of spring wheat were investigated under break water off in different growth period.The results showed that the time of different gradient water content to critical moisture content was shorten with the improvement of growth period.The evapotranspiration of early break water off period was higher than later stage.The daily water consumption was increased before break water off with the progression of growth period and the improvement of water capacity in the same break water off time.The water consumption was increased with the continuation of break water off on the same gradient.