简介：Tocomparetheeffectsofslow-releasenitrogenfertilizeratsixdifferentlevelsontheflagleafchlorophyllfluorescencecharacteristicsofsuperhybridrice,afieldfertilizationexperimentwasconductedwithsuperhybridriceYLiangyou1asatestmaterial.Thephotosyntheticelectrontransportrate(ETR),effectivequantumyield(EQY),photochemicalquenchingcoefficient(qP),andnon-photochemicalquenchingcoefficient(NPQ)offlagleavesweremeasuredattheinitialheading,fullheading,10dafterfullheadingand20dafterfullheadingstages.ResultsshowedthatthevaluesofETR,EQYandqPincreasedwithricedevelopmentfrominitialheadingto20dafterfullheading,whereastheNPQdecreased.Duringthemeasuredstages,ETR,EQYandqPincreasedinitiallyandthendecreasedasnitrogenapplicationamountincreased,buttheypeakedatdifferentnitrogenfertilizerlevels.ThemaximumETRandEQYvaluesappearedatthetreatmentof135kg/hm2N.Inconclusion,theoptimumnitrogenamountforchlorophyllfluorescencecharacteristicsofsuperhybridricewas135180kg/hm2.