Fig. 3

Scanning electron microscopy showing the cell walls of vascular cylinder of the susceptible and the tolerant soybean cultivars when inoculated with P. sojae. a Cell wall of vascular cylinder of the non-infected susceptible soybean cultivar, (b) Cell wall of vascular cylinder of the infected susceptible soybean cultivar, (c) Cell wall of vascular cylinder of the non-infected tolerant soybean cultivar, (d) Cell wall of vascular cylinder of the infected tolerant soybean cultivar. The cell wall of vascular cylinder of the infected tolerant cultivar observed to be thicker compared to the cell wall of vascular cylinder of the susceptible cultivar. Bars: (a-d) 40 µm. Bar charts indicating the relative abundance of cells with thickened cell walls in the vascular cylinder of soybean root as mean ± SE (e; n > 5). Significant differences between the treatments are indicated using letters (a-d) on top of the bars as described by Fisher’s LSD and ANOVA (α = 0.05)