Fig. 5

Competition of Pseudomonas strains in bulk soil or in the rhizosphere of wheat. A Pairwise (left, 1:1 ratio) or triplewise (right, 1:1:1 ratio) competition of Pseudomonas protegens CHA0, Pseudomonas sp. ASV1169 and Pseudomonas sp. ASV1173 in bulk soil or in the rhizosphere of wheat in growing conditions after 9 days without the NatCom. The competition index (CI) was calculated using the formula: CI = (CFUs of Sx at t9 days — CFUs of Sx at t0 days)/(CFUs of Sy at t9 days — CFUs of Sy at t0 days), where Sx and Xy denote the two strains being compared. Four technical replicates of four biological replicates (consisting of equal pools from four rhizospheres or bulk soil samples) were performed. The red dotted line indicates a competition where both strains would not be influenced by the presence of one another. Above this threshold, the competitor strain (CHA0 or ASV1168) outcompetes the other strain. Stacked bar plots below show the average percentage of CFUs recovered per tested strain. Significant pairwise differences are calculated according to Wilcoxon rank-sum test. Not significant (n.s.): p-value > 0.05. B Plant growth-promotion measurements in response to the inoculation of the two or three Pseudomonas strains compared in A. Root and shoot fresh weights were calculated within the four pools of four rhizospheres or shoots per replicate. The length of leaves was measured individually and averaged by the pools of four plants shown for the other parameters. Significant differences were calculated using the Kruskal-Wallis rank-sum test with LSD post hoc analysis and p-value corrected by fdr. Different letters indicate significant differences between groups at p-value < 0.05