Fig. 2

Growth promotion effects of potentially beneficial isolates on Lepidium sativum sprouted seeds (n = 15) and 1103P plantlets (n = 15). (A) Biplot PCA of several growth traits from aerial and root systems. PCA individuals were colored according to their inoculation type (single, double, triple, water, or mix, with the latter combination standing for the eight-isolate consortium). (B) HCA of the different consortia based on phenotypic measurements. Clusters were color-coded based on the gradient of efficiency of isolates in influencing growth, with symbols (+), (++), (+++), and (++++) denoting promotion, and (-) and (--) indicating inhibition compared to conditions treated with water. (Water-like) indicates that the cluster inoculants had the same effect on plant growth as water treatment. (C) Influence on the total length and biomass (stem and root) of single inoculants and consortia composed of two or three different isolates compared to water treatment, with the latter triple-combination exclusively performed on L. sativum. Different letters indicate that the groups have a mean difference that is statistically significant (P < 0.05).