Host genotype strongly influences phyllosphere fungal communities associated with Mussaenda pubescens var. alba (Rubiaceae)

Phyllosphere fungi generally exhibit high species diversity and play important roles in both plant fitness and ecosystem functioning, but the relationship between host plant genotype and phyllosphere fungal community is still poorly understood. In this study, we investigated the fungal communities associated with Mussaenda pubescens var. alba leaves across a regional scale using Illumina MiSeq sequencing of ITS2 sequences. We then characterized both host plant genotype and genetic structure employing microsatellite techniques. A total of 1575 taxonomic operational units (OTUs) of fungi were obtained at a 97% sequence similarity level, which were dominated by members of Dothideomycetes and Eurotiomycetes. We found that fungal community composition was significantly structured by host genotype, and less by geographic distance. Furthermore, a significant genetic differentiation was detected among host plant populations, and plant genetic distance showed a significant positive relationship with fungal community dissimilarity. This study highlights the importance of intraspecific host genetic identity as a primary driver in shaping regional phyllosphere fungal community. (C) 2018 The Authors. Published by Elsevier Ltd.