Data from: Arbuscular mycorrhizal fungi equalize differences in plant fitness and facilitate plant species coexistence through niche differentiation

Mycorrhizal fungi are essential to the establishment of the vast majority
of plant species but are often conceptualized with contradictory roles in
plant community assembly. On one hand, host-specific mycorrhizal fungi may
allow a plant to be competitively dominant by enhancing growth. On the
other, host-specific mycorrhizal fungi with different functional
capabilities may increase nutrient niche partitioning, allowing plant
species to coexist. To resolve the balance of these two contradictory
forces, we used a controlled greenhouse study to manipulate the presence
of two main types of mycorrhizal fungi, ectomycorrhizal fungi (EMF) and
arbuscular mycorrhizal fungi (AMF) and used a range of conspecific and
heterospecific competitor densities to investigate the role of mycorrhizal
fungi in plant competition and coexistence. We find that the presence of
AMF equalizes fitness differences between plants and stabilizes
competition to create conditions for host species coexistence. Our results
show how belowground mutualisms can shift outcomes of plant competition,
and that a holistic view of plant communities which incorporates their
mycorrhizal partners is important in predicting plant community dynamics.