Past spatial structure of plant communities determines of arbuscular mycorrhizal fungal community assembly

Due to the importance of arbuscular mycorrhizal fungi (AMF) in ecosystem productivity, how their communities assemble is a key ecological question. As plant spatial patterns constitute a mosaic of AM fungi habitats, we hypothesized that AM fungal community assembly is determined by plant community structure, both in space and time. To test our hypothesis, we sampled individuals of two host-plant species, Brachypodium pinnatum and Elytrigia repens, from experimental communities cultivated in mesocosms, and used 454 sequencing to assess their AM fungal root colonizers. We related AM fungal community structure to the distribution of neighboring plant species at different spatio-temporal scales. We demonstrated that AM fungal community assembly strongly depends on past plant spatial patterns at small spatial scale (5 cm), indicating that plants growingn at a given locations leave a footprint on the AM fungi community. This spatial scale of response was also influenced by the host-plant species, in particular its clonal propagation. Overall, we highlighted that processes involved in the AM fungal community assembly do not operate at the rough scale of the overall plant community mosaic but are instead locally determined. This gives us some idea of the AM fungal “eye-view” of its host-plant community.This summary corresponds to a first study published from the dataset in New Phytologist