Annual plant competition experiment results and associated mycobiome ASV tables

Major theories regarding microbe-mediated plant community dynamics assume
that plant species cultivate distinct microbial communities. However, few
studies empirically assess the role of species-associated microbial
community dissimilarity in plant competitive dynamics. In this study, we
paired a competition experiment between eight annual forbs with a
characterization of species-associated fungal communities to assess
whether mycobiome dissimilarity is associated with pairwise competitive
dynamics. Using a quantitative approach informed by modern coexistence
theory, we found that fungal dissimilarity was correlated with both
increased stabilizing niche differences and fitness inequalities.
Additionally, we found that the probability of coexistence increased with
mycobiome dissimilarity. When subsetting the community into different
fungal functional groups (pathotrophs, saprotrophs, symbiotrophs), overall
relationships between dissimilarity and competitive dynamics were
independent of these functional groups.  Synthesis: These results
suggest that fungal community divergence may play an important role in
mediating plant competitive dynamics. Although fungal community
dissimilarity is associated with both niche and fitness differences,
complex biotic and/or abiotic interactions belowground may result in an
observed correlation between fungal community dissimilarity and plant
coexistence. Ultimately, this study suggests a novel approach to better
understanding how microbiome dissimilarity may impact host community
dynamics.