(A-B) Relative Pseudomonas abundance in rhizosphere samples after (A), Pi-stress (LP) or (B) treatment with B. subtilis expressing RALF23 (RALF23). The data shown indicate the means ± SDs (n = 3, n refers to biological replicates). **, p < 0.01 (Student's t test). (C-D) Relative Bacillus abundance in rhizosphere samples after (C), Pi-stress (LP) or (D) treatment with B. subtilis expressing RALF23 (RALF23). The data shown indicate the means ± SDs (n = 3, n refers to biological replicates). *, p < 0.05; **, p < 0.01 (Student's t test). (E-F) Relative Geodermatophilus abundance in rhizosphere samples after (E), Pi-stress (LP) or (F) treatment with B. subtilis expressing RALF23 (RALF23). The data shown indicate the means ± SDs (n = 3, n refers to biological replicates). *, p < 0.05; **, p < 0.01 (Student's t test). (G-H) Relative Methylobacillus abundance in rhizosphere samples after (G), Pi-stress (LP) or (H) treatment with B. subtilis expressing RALF23 (RALF23). The data shown indicate the means ± SDs (n = 3, n refers to biological replicates). **, p < 0.01 (Student's t test). 