Fig. 1

a Hypothesized differences in microbial abundance and composition for select root traits that vary in a root system. Within each grey ellipse, circle sizes represent differences in microbial abundance and colors represent differences in composition. b Prevalence plots denoting functionally explicit sampling (top) or pooled sampling of a root system (bottom). Black lines denote a taxon’s relative abundance averaged across all samples (x axis) versus percentage of samples where the taxon is present (y-axis). The yellow star within the plots represents changes in locations on prevalence plots of a putative microbe of interest depending on the sampling approach. c Conceptual model of the rhizosphere region of a root tip. The left portion of the figure shows changes in microbial abundance and diversity based on distance from the root surface; the right portion of the figure displays the locations of rhizosphere compartments, including the rhizoplane (root surface) and rhizosphere soil. d Prevalence plots denoting rhizosphere removal methods that target a region close-to (top), a region distant-from (middle), or a broad region from (bottom) the root surface. Black lines denote a taxon’s relative abundance averaged across all samples (x axis) versus percentage of samples where the taxon is present (y-axis). The yellow star within the plots represents changes in locations on prevalence plots of a putative microbe of interest depending on the sampling approach. Throughout all figures, colored shading around roots represents exudate concentration (conc.) with different colors denoting different exudate compositions and darker shading referring to higher concentrations of exudates in comparison to lighter shading. Figure created with BioRender.com