Discussion
Overall, our results support the idea that soil microorganisms are
drivers of PSF: they influence plant growth in a species-specific way
(Fig. 1, 2) and they respond, to some extent, to plant community
structure (Fig. 3). However, we show that contrary to expectations, the
main microbial drivers of PSF were not pathogens. We also show that
contrary to other studies arguing that microbial α-diversity is a major
driver of various ecosystem functions and plant performance (e.g.,
Delgado-Baquerizo et al. , 2016; Wagg et al. , 2014), here
plant growth response was much more tied to the presence of specific
microorganisms (Fig. 2), rather than to community-level properties such
as richness or diversity (Table 1).