The characteristics of the South Asia high (SAH) and subtropical westerly jets in the summer of 2010 and their relationship with the changes in rainband in China were analyzed. As shown by the results, the SAH in the upper troposphere extended northward relatively late in June 2010. Correspondingly, the subtropical westerly jets on the north side of the SAH jumped northward comparatively late, thus delaying the formation of a strong divergence field in the upper air over the Yangtze-Huaihe River valley. This was one of the main causes for the late onset of plum rains in the Yangtze-Huaihe River valley. In July, there was a vertical structure consisting of upper-level divergence and low-level convergence near the subtropical westerly jets on the north side of the SAH and in the air stream dispersal area on the northeast side of the eastward-extending SAH, which was the dynamic mechanism bringing about frequent and extremely heavy rainstorms during the plum rain period in this year. The SAH in the upper troposphere affected the subtropical high in the lower stratosphere, and thereby led to changes in the main rainband location in China.

Passion fruit wine is a popular fruit wine because of its unique aroma. However, the roles of microorganisms in different fermentation methods, particularly their contributions to aroma formation, are poorly understood. Accordingly, the goal of this study is to reveal the contribution of different fermentation methods to the flavor. Purple passion fruit was used as the experimental focus; high-throughput sequencing technology was used to analyze the microbial community of CF (controlled fermentation) and NF (natural fermentation), and the correlations between the microbial community and physicochemical indices, nonvolatile metabolites and flavor substances were analyzed. In NF, totals of eight fungal phyla, 135 fungal genera, 15 bacterial phyla and 130 bacterial genera were identified. Debaryomyces, Meyerozyma, and Wickerhamomyces were the dominant fungal genera, and Paucibacter and Pantoea were the dominant bacterial genera. In CF, totals of 11 fungal phyla, 389 fungal genera, 15 bacterial phyla and 128 bacterial genera were identified. Meyerozyma, Cladosporium, and Saccharomyces were the dominant fungal genera, and Paucibacter, Achromobacter, and Lactobacillus were the dominant bacterial genera. In NF, Wickerhamomyces, Achromobacter, Bifidobacterium and Lactobacillus were positively correlated with flavor substances such as ethylene glycol acetate formate, 2-pentanol, acetate, phenylethyl alcohol and 1-butanol, 3-methyl-. In CF, Saccharomyces, Achromobacter and Lactobacillus were positively correlated with a variety of esters and alcohols such as decanoic acid, ethyl ester, dodecanoic acid, ethyl ester and phenylethyl alcohol. Overall, this study can provide a valuable resource for further developments and improve the aromatic quality of passion fruit wine.

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