为研究冬小麦对花前水分胁迫的响应,在大田条件下,以济麦20为材料,设置正常水分(CK)、中度干旱(MD)和重度干旱(SD)三个水分处理进行试验。水分胁迫下,冬小麦春季分蘖减少,有效分蘖比例增加,叶面积、株高和物质累积量等均减小,生长过程受阻。叶面积变化主要由叶片长度的减小引起,且对旗叶影响程度低于低位叶；株高的降低主要是第IV、第V高位节间长度的降低,第I、第II低位节间反而有所增长；次生根发生减少,通过减少根密度及增加根长适应干旱；物质积累因水分胁迫而受阻,且物质向根系的分配增加,根冠比增大。水分胁迫下,冬小麦花前生长发育受阻,地上部通过减小生长量适应水分胁迫,降低幅度随胁迫加剧而增大；根系在减少发生的同时,增加根长,扩大吸收面积。

In order to study the response of winter wheat to the water stress before flowering stage, the winter wheat of Jimai20 is taken as the research object by measuring agronomic characteristics under three different water stresses in the field conditions. The result shows that under water stress, the spike rate increases while spike per hectare reduces. Leaf area, height and, matter accumulation are all blocked. The decrease of length rather than the width is mainly caused by the changes in the area of the fourth leaf. The response from flag leaf is less sensible than that from the leafs in lower positions. The height decrease is due to the length decrease between modal Ⅳ and Ⅴ. As water stress increases, all the agronomic characters mentioned above decline. Comparing with leaves and intermodal, the change for root system is more complicated. The number of secondary roots reduces, however the lengths increase. Matter accumulation delays by water stress, and the distribution of matter increases toward root causing root-shoot ratio increase. The plants decrease drought damage though reducing the root density, leaf area, intermodal length, and increasing root length.