FIG. 1.

Ralstonia solanacearum R3bv2 had reduced virulence following long-term incubation in geranium tissue at −20°C. Young Bonny Best tomato plants were inoculated through a cut petiole with 250 to 350 CFU of R3bv2 strain UW551 either taken from water stock (closed triangles) or recovered from infected geranium tissue incubated at −20°C for 6 to 7 months (closed circles). Plants were rated daily on a disease index scale of 0 to 4, where 0 indicated healthy plants and 4 indicated 75 to 100% wilted plants. Each point represents the average disease index for four independent experiments, consisting of 16 plants per treatment; treatments differed by repeated-measures ANOVA (P < 0.001).