Fig. 7.

Apple root exudates mediate the recruitment of pathogen-suppressing Bacillus. a DI of Fpmd MR5-challenged apple plants grown on sterilized artificial soil inoculated with water or slurries of soils preconditioned with mixtures of ACs or FCs. b DI of Fpmd MR5-challenged apple plants grown on sterilized artificial soil inoculated with filter-sterilized water, ACs, or FCs. c DI of Fpmd MR5-challenged apple plants grown on sterilized artificial soil inoculated with water or FCs and ACs mixed in a ratio of 1:9, 5:5, or 9:1 (v/v). d DI of Fpmd MR5-challenged apple plants grown on sterilized artificial soil inoculated with water or filter-sterilized FCs and ACs mixed in a ratio of 1:9, 5:5, or 9:1 (v/v). e Abundance of Fpmd MR5 in rhizosphere soil inoculated with (left) water or slurries of soils preconditioned with mixtures of ACs or FCs, or (right) filter-sterilized water, ACs, or FCs. f Abundance of Fpmd MR5 in rhizosphere soil inoculated with (left) water or FCs and ACs mixed in ratios of 1:9, 5:5, or 9:1 (v/v), (right) water or filter-sterilized FCs and ACs mixed in the same ratios. g Numbers and heatmap illustrating the effect of culturable isolates on Fpmd MR5 pathogen growth inhibition in laboratory assays (mean, n = 3) and on disease suppression in a glasshouse experiment with apple plants relative to a non-Bacillus-inoculated control treatment (mean, n = 3). Bars show average ± SD of 3 replicates. Different lowercase letters indicate significant differences (Tukey’s test, P ≤ 0.05). “ns” denotes no significant difference (Tukey’s test, P > 0.05). Black dots represent individual replicate values