Fig. 6

Testing of the effect of dopamine as a biostimulant of beneficial taxonomic groups. Box-and-whiskers plots show the abundance of select bacterial genera within the orders Xanthomonadales (A) and Nevskiales (B), predicted by network analysis to be linked to the utilization of dopamine and seedling biomass measured upon harvest (8 weeks post-planting; n = 10) (C). 16S rRNA gene sequence data was obtained from DNA extracted from rhizosphere soil collected 4 weeks post-planting into the respective treatments (n = 5). Values plotted represent the 25th percentile, the median, the 75th percentile; whiskers extend to the minimum and maximum. In A and B, multiple comparisons were carried out with Dunn’s test following the Kruskal–Wallis non-parametric test. In C, multiple comparisons were performed using Tukey’s test following ordinary one-way ANOVA. Unlike the original experiment, seedling biomass was similar between BjSa SM and NTC