Understanding the current and future distributions of plant pathogens is critical to predict the plant performance and related economic benefits in the changing environment. Yet, little is known about the roles of environmental drivers in shaping the profiles of fungal plant pathogens in phyllosphere, an important habitat of microbiomes on Earth. Here, using a largescale investigation of Eucalyptus phyllospheric microbiomes in Australia and the multiple linear regression model, we show that precipitation is the most important predictor of fungal taxonomic diversity and abundance. The abundance of fungal plant pathogens in phyllosphere exhibited a positive linear relationship with precipitation. With this empirical dataset, we constructed current and future atlases of phyllosphere plant pathogens to estimate their spatial distributions under different climate change scenarios. Our atlases indicate that the abundance of fungal plant pathogens would increase especially in the coastal regions with up to 100-fold increase compared with the current abundance. These findings advance our understanding of the distributions of fungal plant pathogens in phyllospheric microbiomes under the climate change, which can improve our ability to predict and mitigate their impacts on plant productivity and economic losses.

Introduction: Phyllosphere microbiome is intrinsically linked to plant performance and ecosystem functioning. However, our knowledge about the role of ecological processes in shaping the biogeography of different phyllosphere microbial communities is scarce.Materials and Methods: Here, we compared the biogeographic patterns of bacterial and fungal communities in phyllosphere samples of plants belonging to the genus of Eucalyptus of the Myrtaceae family collected from an over 4000 km transect. We investigated the relative importance of two major ecosystem processes (stochastic vs. deterministic) in shaping phyllosphere microbial community assemblies.Results: Our results demonstrated that the neutral community model, which can quantify the degree of a community assembly determined by stochastic processes, explained 64.2% of the variations in bacterial community assembly, which had a normalized stochasticity ratio of 71.8%. These results suggest that the dominant role of stochastic processes in shaping bacterial community assembly. In contrast, phyllosphere fungal community assembly was mainly shaped by deterministic processes as revealed by a relatively small explanation rate of the neutral community model (48.7%) and a normalized stochasticity ratio of 25.1%. Variation partitioning analysis and random forest modelling results indicated that climatic factors, particularly mean annual precipitation and aridity index, were important in driving both bacterial and fungal biogeographic patterns in the phyllosphere. Edaphic factors, such as soil organic and mineral nitrogen content, were more closely related to fungal community assembly than to bacterial community assembly. The differential responses of bacterial and fungal communities to environmental factors could be attributed to the different traits of bacteria and fungi, that is, the higher potential dispersal rate and wider habitat niche of bacteria than fungi. Conclusion:Our findings demonstrated that phyllosphere bacterial and fungal communities followed distinct community assembly processes, which is supported by the 'size plasticity' hypothesis that smaller organisms (bacteria) are less influenced by environmental conditions and are more homogeneous across space than larger

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Termites are pivotal ecosystem engineers in tropical and subtropical habitats, where they construct massive nests ('mounds') that substantially modify soil properties and promote nutrient cycling. Yet, little is known about the roles of termite nesting activity in regulating the spread of antimicrobial resistance (AMR), one of the major Global Health challenges. Here, we conducted a large-scale (> 1500 km) investigation in northern Australia and found distinct resistome profiles in termite mounds and bulk soils. By profiling a wide spectrum of ARGs, we found that the abundance and diversity of antibiotic resistance genes (ARGs) were significantly lower in termite mounds than in bulk soils (P < 0.001). The proportion of efflux pump ARGs was significantly lower in termite mound resistome than in bulk soil resistome (P < 0.001). The differences in resistome profiles between termite mounds and bulk soils may result from the changes in microbial interactions owing to the substantial increase in pH and nutrient availability induced by termite nesting activities. These findings advance our understanding of the profile of ARGs in termite mounds, which is a crucial step to evaluate the roles of soil faunal activity in regulating soil resistome under global environmental change.