Site‐specific responses of foliar fungal microbiomes to nutrient addition and herbivory at different spatial scales

• Published in: Ecology and evolution Vol. 9; no. 21; pp. 12231 - 12244
• Main Authors: Lumibao, Candice Y., Borer, Elizabeth T., Condon, Bradford, Kinkel, Linda, May, Georgiana, Seabloom, Eric W.
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.11.2019; John Wiley and Sons Inc; Wiley
• Subjects: Andropogon gerardii; Animal behavior; Bioinformatics; Competition; Composition; Ecological effects; Endophytes; Environmental changes; Environmental impact; Fertilization; Fungi; Herbivory; Host plants; Leaves; Microbiomes; Microorganisms; nitrogen, phosphorus, potassium; Nutrient Network; Nutrients; Original Research; phylogenetic diversity; Phylogenetics; Phylogeny; Plant communities; Plant diversity; plant fungal endophytes; Plant tissues; spatial variation; Species diversity; Taxa; United States > US; nitrogen, phosphorus, potassium; spatial variation; Andropogon gerardii; Nutrient Network; plant fungal endophytes; phylogenetic diversity
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.5711

The plant microbiome can affect host function in many ways and characterizing the ecological factors that shape endophytic (microbes living inside host plant tissues) community diversity is a key step in understanding the impacts of environmental change on these communities. Phylogenetic relatedness among members of a community offers a way of quantifying phylogenetic diversity of a community and can provide insight into the ecological factors that shape endophyte microbiomes. We examined the effects of experimental nutrient addition and herbivory exclusion on the phylogenetic diversity of foliar fungal endophyte communities of the grass species Andropogon gerardii at four sites in the Great Plains of the central USA. Using amplicon sequencing, we characterized the effects of fertilization and herbivory on fungal community phylogenetic diversity at spatial scales that spanned within‐host to between sites across the Great Plains. Despite increasing fungal diversity and richness, at larger spatial scales, fungal microbiomes were composed of taxa showing random phylogenetic associations. Phylogenetic diversity did not differ systematically when summed across increasing spatial scales from a few meters within plots to hundreds of kilometers among sites. We observed substantial shifts in composition across sites, demonstrating distinct but similarly diverse fungal communities were maintained within sites across the region. In contrast, at the scale of within leaves, fungal communities tended to be comprised of closely related taxa regardless of the environment, but there were no shifts in phylogenetic composition among communities. We also found that nutrient addition (fertilization) and herbivory have varying effects at different sites. These results suggest that the direction and magnitude of the outcomes of environmental modifications likely depend on the spatial scale considered, and can also be constrained by regional site differences in microbial diversity and composition. The plant microbiome can affect host function in many ways yet our understanding of the ecological and environmental factors that shape plant microbiomes is limited, especially within the evolutionary context of phylogenetic relatedness among members of a community. We characterized the responses of foliar fungal endophytic microbiomes of Andropogon gerardii to nutrient addition and herbivory at different spatial scales in a distributed, regional‐scale experiment. Despite increasing fungal diversity and richness, phylogenetic diversity of fungal microbiomes did not differ systematically when summed across increasing spatial scales although nutrient addition and herbivory have varying effects at different sites, suggesting that that the direction and magnitude of the outcomes of environmental modifications likely depend on the spatial scale considered and can also be constrained by regional site differences in microbial diversity and composition.