Figure 1.

Behaviour and virulence of Ralstonia solanacearum strain OE1–1, the ralfuranone‐deficient mutant ΔralA and the complemented ΔralA mutant ralA‐comp in tomato plants. (a) The population of R. solanacearum strains in the roots of tomato plants inoculated by root dipping was analysed using Hara–Ono medium. CFU, colony‐forming unit. (b) Ralstonia solanacearum strains in roots (I) and stems (II and III) of tomato plants at 10 days after inoculation by root dipping were detected using the plate‐printing assay. (c) Bacterial wilt on tomato plants inoculated with R. solanacearum strains by root dipping was assayed. Plants were rated on a 0–5 disease index scale: 0, no wilting; 1, 1%–25% wilting; 2, 26%–50% wilting; 3, 51%–75% wilting; 4, 76%–99% wilting; 5, dead. Bars indicate standard errors. Asterisks indicate a significant difference from the wild‐type (P < 0.05, t‐test).