| A plant efficacy analyzer was used to study the effects of reducing irrigation on the kinetics parameters of chlorophyll fluorescence of flag leaves in filling stage and grain yield of winter wheat with shielding from rainfall during its growth.The result showed that the chlorophyll content and Tm of different irrigation treatments were high in prophase and then reduced gradually in telophase of grain filling.But(Fv/Fo) and(Fv/Fm) had little difference between prophase and metaphase of grain filling and then reduced rapidly in telophase of grain filling.The chlorophyll content,Tm,Fv/Fo and Fv/Fm without irrigation were low,however that irrigated one time in heading stage was high.Reducing irrigation decreased grain yield and water consumption,but increased water utilization efficiency. |