Fig. 3: Influence of bacterial diversity loss of root-associated microbes (RAMs) on plant susceptibility to Meloidogyne incognita.
a Schematic representation of the design of the microbe gradual-removal experiment. Six levels of dilution (L1: 100; L2: 10-1; L3: 10-2; L4: 10-4; L5: 10-6; L6: 10-8) of the soil suspension were used as inocula to create a gradient of microbial diversity in soils. b Chord diagram showing changes in the relative abundance of bacterial RAMs in the rhizosphere at the phylum level. The chord diagram can depict the relationship between serial dilution treatments by displaying the relative abundance of bacterial microbes at the phylum level. c Changes in rhizosphere bacterial α-diversity with increasing simplification of microcosms. d Principal coordinate analyzes (PCoA) based on Bray-Curtis distance showing the distinction of rhizosphere bacterial RAMs of M. incognita-infected plants. Statistical significance was determined using the permutational multivariate analysis of variance (PERMANOVA). e Changes in rhizosphere bacterial β-diversity with increasing simplification of microcosms. f Symptoms of the root-knot disease in roots. g, h Changes in gall and egg mass numbers per gram of plant roots with increasing simplification of microcosms (mean ± SEM). Different letters indicate significant differences by one-way ANOVA with post hoc Tukey HSD test (p < 0.05). N  =  9 biologically independent samples. i Functionality in relation to the diversity of bacterial RAMs. The Fric index was calculated using the dbFD function in the ‘FD’ R package. j Gall and egg mass numbers per gram root in relation to the diversity and functionality of bacterial RAMs. Values are expressed as a ratio of the most complete microbial consortium. In c, e, i, and j, the curve represents the linear regressions and the shaded area indicates 95% regression confidence interval. Source data are provided as a Source Data file.
