土壤水变动对冬小麦生长产量及水分利用效率的影响

采用盆栽和管栽试验，研究土壤水变动对冬小麦地上部生长、产量及水分利用效率的影响。结果表明：株高对水分胁迫的发生时期较敏感，叶面积对水分胁迫的持续时间更敏感，与其他水分胁迫处理相比，分蘖至拔节阶段水分胁迫处理的株高最小，分蘖至孕穗阶段水分胁迫处理的叶面积最小。冠重主要受胁迫持续时间的影响，分蘖至孕穗阶段水分胁迫处理的冠重最小。水分胁迫对冬小麦穗数和WUE的影响基本上表现为正效应，而对每穗粒数、千粒重及产量的影响则全部为负效应。在各水分胁迫处理中，拔节至孕穗阶段经中度水分胁迫后抽穗期复水的处理，产量最高，达到充分供水对照的62%；分蘖至拔节阶段经中度水分胁迫后孕穗期复水的处理，WUE最大。试验结果表明，冬小麦株高、叶面积及各产量要素对土壤水变动的响应存在差异。

Effects of fluctuated soil moisture on the growth, yield and water use efficiency of winter wheat

The pot and tube experiment were conducted. Effects of fluctuated soil water on shoot growth, grain yield and water use efficiency of winter wheat were investigated. The results indicate that plant height is sensitive to the phase of water deficit, and leaf area is more sensitive to the duration of water deficit. Compared to other water stressed treatments, plant height of winter wheat exposed to water stress during the tillering to jointing stage is the minimum, and leaf area of winter wheat exposed to water stress during the tillering to booting stage is the minimum. Shoot weight is mainly influenced by the duration of water stress, and shoot weight of winter wheat exposed to water stress during the tillering to jointing stage is the minimum. Water stress has a positive effect on the plant spike number and water use efficiency, while has the negative effects on the grain number per spike, 1000-grain weight and grain yield. Amongst all water stressed treatments, the treatment rewatered at the heading stage after moderate water stress from the jointing stage to the booting stage has the maximal grain yield which is up to 62% of the control under sufficient soil water condition, the treatment rewatered at the booting stage after moderate water stress from the tillering stage to the jointing stage has the maximal water use efficiency. The responses of plant height, leaf area, grain number, 1000-grain weight etc, to fluctuated soil water condi- tion are different.