Effects of water stress on physiological and agronomic features of winter wheat

Pot experiments with four levels of soil moisture at different growing stages of winter wheat were carried out to study water stress on physiological and agronomic factors of winter wheat. The growing stage of winter wheat was divided into four stages: recovering-jointing, jointing-booting, booting-heading, flowering-maturing. Under different soil-water conditions, the physiological and agronomic factors of winter wheat were measured continually. The results show that water stress affected plant height, leaf area, chlorophyll content, photosynthesis, transpiration and water use efficiency (WUE). The time when the maximum points in diurnal change for leaf photosynthesis and transpiration rate appeared was earlier under water stress than that without water stress, which was beneficial for crop to use limited soil moisture more efficiently under stress condition. Transpiration was more sensitive to water stress than photosynthesis and transpiration rate was more readily controlled by stomatal conductance.