Abstract: Blueberry fruits（‘Powder Blue’）were used as experimental material,tissue isolation method,Koch′s law,morphological identification and rRNA-ITS sequence homology analysis methods were used to study the main rot-causing pathogen species of blueberry fruits and to screen for suitable high-efficiency and low-toxicity biocides,in order to provide reference for the prevention and control of berry fruits postharvest diseases.The results showed that the pathogens causing blueberry rot during low-temperature storage were Botrytis cinerea,Alternaria alternata,Colletotrichum gloeosporioides,Neopestalotiopsis clavispora and Neofusicoccum parvum.For the first time,Colletotrichum gloeosporioides was found to be the dominant pathogen causing fruit rot of‘Powder Blue’blueberry.The indoor toxicity test showed that ethylicin showed strong antibacterial activity against Colletotrichum gloeosporioides,with EC₅₀ value of 123.16mg·mL^-1,followed by matrine,zhongshengmycin,kasugamycin and eugenol,with EC₅₀value of 231.23,519.55,546.29,865.26mg·mL^-1 respectively.Therefore,ethylicin could be used as an effective biocide for field control of blueberry in the later stage.