Biotic and abiotic factors shape arbuscular mycorrhizal fungal communities associated with the roots of the widespread fern Botrychium lunaria (Ophioglossaceae)

• Published in: Environmental Microbiology Reports
• Main Authors: Sandoz, Frédéric Alexandre, Bindschedler, Saskia, Dauphin, Benjamin, Farinelli, Laurent, Grant, Jason, Hervé, Vincent
• Other Authors: Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, Neuchâtel, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland, Fasteris SA Plan-les-Ouates, Switzerland, Max Planck Institute for Terrestrial Microbiology, Marburg
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: [SDE]Environmental Sciences; [SDV]Life Sciences [q-bio]; Botrychium lunaria
• Online Access: https://hal.science/hal-03701741; https://hal.science/hal-03701741/document; https://hal.science/hal-03701741/file/19_Sandoz_et_al_2020_-_EM_Reports.pdf; https://doi.org/10.1111/1758-2229.12840

International audience Arbuscular mycorrhizal fungi (AMF) play central roles in terrestrial ecosystems by interacting with both above and belowground communities as well as by influencing edaphic properties. The AMF communities associated with the roots of the fern Botrychium lunaria (Ophioglossaceae) were sampled in four transects at 2400 m a.s.l. in the Swiss Alps and analyzed using metabarcoding. Members of five Glomeromycota genera were identified across the 71 samples. Our analyses revealed the existence of a core microbiome composed of four abundant Glomus operational taxonomic units (OTUs), as well as a low OTU turnover between samples. The AMF communities were not spatially structured, which contrasts with most studies on AMF associated with angiosperms. pH, microbial connectivity and humus cover significantly shaped AMF beta diversity but only explained a minor fraction of variation in beta diversity. AMF OTUs associations were found to be significant by both cohesion and co-occurrence analyses, suggesting a role for fungus–fungus interactions in AMF community assembly. In particular, OTU co-occurrences were more frequent between different genera than among the same genus, rising the hypothesis of functional complementarity among the AMF associated to B. lunaria. Altogether, our results provide new insights into the ecology of fern symbionts in alpine grasslands.