Fig. 6: Pyoverdine secreted by Pseudomonas spp. is essential to improve peanut iron nutrition and biomass.

a Phenotypes of peanut plants under control conditions and when treated with a Pseudomonas aeruginosa PAO1 mutant without pyoverdine secreting ability (PAO1 ΔpvdDpchEF), Pseudomonas aeruginosa PAO1 wild type (PAO1 WT) with pyoverdine secretion ability, and Pseudomonas sp. 1502IPR-01 with pyoverdine secretion ability (all rhizosphere application). b Soil Plant Analysis Development (SPAD) values, active iron in young leaves, available iron in the rhizosphere, biomass and Fe(III) reduction capacity of peanut under control conditions and the three treatments (PAO1ΔpvdDpchEF, PAO1 WT and 1502IPR-01) in greenhouse conditions. For b bars and error bars represent the mean ± standard deviation (SD) and dots represent individual values. ANOVA with LSD post-hoc test was used when data followed the normal distribution and had homogenous variances. For skewed data sets or data with heterogeneous variances, the BoxCox transformation algorithm was applied. When the data still did not meet the assumptions of parametric tests, Kruskal–Wallis test with Dunnett T3 test was used. Different letters indicate significant differences between groups. Multiple testing corrections were performed by the BH algorithm. Asterisks indicate significant differences between two groups: *p < 0.05; **p < 0.01; ***p < 0.001, n.s not significant. For all parameters, n represents the number of biologically independent samples. Two-sided tests were used for alternative hypothesis testing. Source data are provided.