The bacterial communities of Alaskan mosses and their contributions to N2-fixation

Abstract Background Mosses in high-latitude ecosystems harbor diverse bacterial taxa, including N 2 -fixers which are key contributors to nitrogen dynamics these systems. Yet the relative importance of moss host species, and environmental factors, structuring microbial communities their -fixing potential remains unclear. We studied 26 boreal tundra species across 24 sites Alaska, USA, from 61 69° N. used cultivation-independent approaches characterize variation moss-associated as a function identity site characteristics. also measured -fixation rates via 15 isotopic enrichment identified bacteria using available literature genomic information. Results Host evolutionary history were both highly predictive microbiome composition, highlighting strong phylogenetic coherence communities. Although less important, light availability temperature influenced composition microbiome. Finally, we putative specific some hosts, outside well-studied cyanobacterial clades. Conclusions The effect on demonstrates mosses’ utility for understanding plant-microbe interactions non-leguminous Our work highlights likely novel taxa ecosystems.