Arabis alpina fungal microbiome. Arabis alpina fungal microbiome

Most land plants live in association with mycorrhizal fungi and rely on this symbiosis to obtain phosphorus (P). Intriguingly, some plant species such as Arabis alpina lost the ability to establish this partnership raising the question of how they can thrive in P-depleted habitats. To understand the contribution of other plant-fungus interactions to this observation, we are missing information about the structure and function of the root fungal microbiota in non-mycorrhizal plants. This study closes this gap by exploring the root fungal microbiome of A. alpina with the hypothesis that some of its components can promote plant P acquisition. Using amplicon sequencing on the fungal ITS2 we studied the root-associated fungal microbiome of A. alpina growing under different conditions, and identified a core microbiome of 15 taxa consistently detected in its roots. Remarkably, this core microbiome excluded mycorrhizal fungi but included a Helotiales taxon whose relative abundance in roots correlated with high P accumulation in the plant shoot.