Abstract:

In order to study the effect of drought stress on physiological characteristics and irrigation water use efficiency during growth and development period, the high-yielding, high-quality and drought-resistant new varieties of spring wheat named ‘Dingfeng 18’ and ‘Dingfeng 19’were used as materials. Well watered (WW), moderate soil drought (MD) and severe soil drought (SD) from the tillering stage to maturity stage were treated to study their effects on wheat leaf water potential, photosynthetic rate, grain filling rate, yield components and irrigation water use efficiency. The results show that compared with WW treatment, the leaf water potential significantly reduced (p<0.05) under MD and SD treatment, and it reached normal level through night recovery under MD treatment, but it could not restore under SD treatment. The photosynthesis of leaves was significantly inhibited under SD treatment, there was no significant difference in photosynthesis of leaves between MD and WW treatments (p>0.05). Compared with WW treatment grain filling rate, grain weight, grain number, 1000-grain weight and yield significantly increased under MD treatment and significantly decreased under SD treatment. There was no significant difference in the bulk weight between different treatments (p>0.05). Two years experiments results of the two different varieties were basically consistent. Moderate water deficit was beneficial to increase wheat yield, thus improving irrigation water use efficiency.

Key words: Key words: spring wheat, drought stress, physiological characteristics, yield components, irrigation water use efficiency

摘要：

为研究干旱胁迫对春小麦生长发育阶段生理性状和灌水利用效率的影响，以高产优质抗旱春小麦新品种‘定丰18号’和‘定丰19号’为材料，对其分蘖期到成熟期进行正常供水（WW）、轻度土壤干旱（MD）和重度土壤干旱（SD）3种不同水分处理，研究3种处理对小麦叶片水势、光合速率、籽粒灌浆速率、产量构成因素以及灌水利用效率的影响。结果表明，与WW处理比较，MD和SD处理显著降低了叶片水势（p＜0.05），MD处理通过夜间恢复其叶片水势可达到正常水平，SD处理不能恢复；SD处理显著抑制了叶片光合作用，MD处理与WW处理无显著差异（p＞0.05）；与WW处理相比，MD处理籽粒灌浆速率、粒重、穗粒数、千粒重和产量显著增加，而SD处理则显著降低（p＜0.05），不同处理间容重无显著差异（p＞0.05）。两个不同小麦品种的两年试验结果基本一致，适度的水分亏缺有利于小麦增产，从而可提高其灌水利用效率。

关键词: 春小麦, 干旱胁迫, 生理性状, 产量构成因素, 灌水利用效率