Abstract: Different post-harvest pre-cooling methods can influence the incidence of decay in cherry fruits, mainly due to the development of fungal community on the fruit surface. The composition and diversity of fungal community on the surface of Red Agate cherry fruit subjected to different pre-cooling treatments were analyzed during subsequent cold storage for up to 30 days, with focus on the changing trend of the dominant microbes. The internal transcribed spacer (ITS) sequence was determined by high throughput sequencing. The results showed that compared with cold air cooling, treatment with unozonated or ozonated ice water reduced the abundance and alpha diversity of the fungal microbiome during the storage period. The initial dominant fungal composition was similar in the three pre-cooling groups, including Aureobasidium pullulans, Pleosporales (one operational taxonomic unit (OTU)), Alternaria sp. (4 OTUs) and Davidiellaceae (3 OTUs). Both ice water treatments reduced the proportion of initial pathogenic fungi and increased the proportion of biocontrol fungi (Aureobasidium pullulans). During storage, the dominant fungi in each group developed. On the 30th day, Davidiellaceae (3 OTUs) became the dominant fungus in cold air treated samples. In unozonated ice water treated samples, Aureobasidium pullulans developed into the dominant fungus; however, the proportion of Pleosporales (1 OTU), Alternaria sp. (4 OTUs) and Davidiellaceae (3 OTUs) and Davidiella tassiana increased to 16.28%, 8.23%, 8.40% and 8.96%, respectively, which may cause spoilage on the surface of cherry fruit. Pleosporales was the dominant fungus in the ozonated ice water treatment group, and Alternaria (4 OTUs) accounted for 14.26% of the total fungi. These results revealed the effects of pre-cooling methods on the fugal community of Red Agate cherry fruit during post-harvest cold storage, which will provide fundamental data for the choice of pre-cooling methods and the application of other anti-fungal technologies.

Key words: cherry, pre-cooling, fungal community, cold storage