Abstract:Green walnut fruit of ‘Zhonglin 5’（early mature）,‘Liaoning 4’ (middle-mature),‘Xifu 1’ (middle-late mature) were harvested on three stages of early,middle and late August,and stored at 0~1 ℃.Physiological indices and preservation effect during the storage were measured and valued.(1)Respiration intensity of fruits from each harvest stage and each variety all showed two-peak curve trend.Those harvested in middle August appeared the earliest respiration peak,also presented one more Cx activity peak during the first period of storage and the earliest increase of PG activity,which resulted in the most decrease in acid value of kernel and the highest decay rate of fruit after storage.(2)Among fruit of three varieties,the physiological indices changed almost in the same way.After 54-day storage,the decay rate of ‘Liaoning 4’ was the highest,followed by ‘Zhonglin 5’,and ‘Xifu 1’ was the lowest.(3)Kernel of ‘Liaoning 4’ with higher soluble protein content showed more decline rate than those with lower content.In conclusion,walnut fruit harvested on mid-August are less tolerant to store due to its vigorous postharvest physiological metabolism.