Spatiotemporal pattern of the fungal community
In terms of alpha diversity, the observed OTU richness in the phyllosphere, rhizosphere, rhizoplane, and soil compartments were roughly equal, while the leaf endosphere showed significantly higher alpha diversity in Banna compared to Hainan, while the root endosphere exhibited the opposite trend (Figure S5a, Table S1). When considering the seasonal effect, the observed OTU richness of bacterial communities in the leaf endosphere (P <0.01), root endosphere (P <0.05), and rhizoplane (P <0.01) were significantly higher during the rainy season compared to the dry season (Figure S5b, Table S1). However, when analyzing the seasonal effect separately, distinct patterns were observed. In Banna, the alpha diversity of all compartments was significantly higher during the rainy season compared to the dry season. In Hainan, although the alpha diversity of the root endosphere and rhizoplane were similar between the rainy and dry seasons, and the leaf endosphere showed significantly higher alpha diversity during the rainy season, the phyllosphere, rhizosphere, and soil compartments exhibited significantly higher alpha diversity during the dry season. Overall, the trend in alpha diversity was higher in the dry season compared to the rainy season in Hainan (Figure 3a).
When analyzing the microbial composition based on the Bray-Curtis distance, we observed that geographical location had a significant effect on the beta diversity of fungal communities in all compartments (P <0.01), while seasonal effects were not significant (Figure 3). For instance, geographical location accounted for 6.62%, 7.35%, 9.13%, 8.07%, 17.67%, and 18.78% of the variation in the soil, rhizosphere, rhizoplane, root endosphere, phyllosphere, and leaf endosphere, respectively. Additionally, we observed a much greater effect of site variation compared to seasonal variation in all compartments (Figure S6). In summary, our findings indicate that geographical location/site has a significant impact on fungal composition, while season does not.