Abstract:

Abstract：Under precipitation and irrigation condition, we took wheat variety Qingmai 6 as the object of study. Studying the response that rate of photosynthesis and transpiration, stomatal conductance, water use efficiency to light intensity in the wheat filling period, researching the relativity to each photosynthetic characteristics. It showed that photosynthetic rate and stomatal conductance were increasing with the light intensity under precipitation and irrigation conditions, which were all simulated with Michaelis-Menten equation. Photosynthetic rate and stomatal conductance with irrigation treatment were higher than that of precipitation under higher light intensity, transpiration rate with irrigation treatment was higher than that of precipitation, but water use efficiency was lower than that of precipitation. The rate of photosynthesis and transpiration had remarkable linearity relation because of in-phase of gas exchange, but the effect of water lack to transpiration rate was more direct and intense than that to photosynthetic rate.