Statistical inference of keystone taxa reshaping the assembly rules of forest root microbiomes.

Several endophytic fungi, including Phialocephala and Oidiodendron, are strongly associated with reorganization of forest root microbiome assembly landscape topography along abundance gradients in Japan.

• Why it matters: Keystone taxa that reorganize below-ground microbial assembly are difficult to identify, limiting links between microbiome structure and ecosystem-scale processes.
• What they did: A statistical framework was applied to 1,270 root samples from a cool-temperate forest in Japan to reconstruct probabilistic assembly landscapes and test associations with abundance gradients and mycorrhizal symbiosis.
• The result: Independent Europe datasets confirm these genera are significantly associated with changes in mycorrhizal colonization patterns, and prokaryotic state transitions are linked to abundance gradients of Candidatus Udaeobacter and endophytic fungi.