Figure 1. Hypothetical effects of bacterial richness on fungal pathogen inhibition at the plant-soil interface.

(a), different wheat varieties culture high or low richness of soil bacteria (Pseudomonas spp.) which leads to low or high suppression of fungal pathogens in the soil (take-all fungus), respectively. (b), as bacterial richness increases, antagonism between bacterial genotypes increases which causes a decrease in ability of the bacterial community to combat fungal pathogens. (c), an increase in fungal pathogen inhibition decreases disease incidence and leads to an increase in crop yield.