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 condition are different.