Composition and Assembly of the Endophytic Fungal Community of Alpine Rhododendron Hosts Along Elevation Gradients

Alpine mountain ecosystems are highly sensitive to global warming and threatened by climate change. Elevation gradients are frequently used as space-for-time surrogates for climate change in mountain ecosystems due to their correspondence with climate variables over short geographic distances. However, the distribution patterns of fungal communities in perennial woody plants along elevations in this ecosystem and how elevation and host identity affect them remain unclear. In this work, we used Illumina MiSeq DNA sequencing technology to study the rhizosphere soil fungal community and root and leaf endophytic fungal community assembly of alpine Rhododendron communities across a 3,100- to 4,100-m elevation gradient on Jiaozi Mountain, Southwest China. The abundance and diversity of fungi in different compartments varied among elevation gradients and hosts. The fungal community assembly in each compartment was mainly influenced by stochastic processes. However, the contribution of homogeneous selection, dispersal limitation, and drift varied among host identities and elevations in different compartments. The diversity and composition of rhizosphere soil, root, and leaf guilds and the overall abundance of fungal functional groups tracked the Rhododendron host identity more closely than elevation did. Most indicator taxa of fungi were putative saprotrophs. These findings will improve our understanding of the maintenance of alpine Rhododendron communities along elevation gradients. Copyright (c) 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.