Figure 6.

Root colonization by B. subtilis ancestor and isolate Ev7.3 in the presence of a synthetic, soil-derived community

The ancestor and evolved isolate, Ev7.3, were tested for the ability to colonize the root in the presence of a synthetic, soil-derived bacterial community. B. subtilis ancestor or Ev7.3 and the community were co-inoculated onto A. thaliana roots in four different ratios: 0.1:1, 1:1, 10:1, and 100:1 of B. subtilis and community, respectively. Root colonization after 48 h was quantified as log10-transformed productivity (CFU/root). Each plot shows the resulting root colonization at the given inoculation ratio of B. subtilis (left) and the co-inoculated community (right). Magenta: Ancestor and the corresponding community co-inoculated with the ancestor. Green: Ev7.3 and the community co-inoculated with Ev7.3. The cross represents the mean (N = 5–15). Within each inoculation ratio, statistical significance between B. subtilis ancestor and Ev7.3, and between the communities co-inoculated with the ancestor or with Ev7.3 was tested with a Two-sample t-test (Welch’s Two-sample t-test when unequal variance). ∗∗p < 0.01. See also Figures S6 and S7.