UW551ΔlecM and UW551ΔaidC had reduced survival in potato tubers at 4°C.

<p>Potato tubers were injected with different <i>R</i>. <i>solanacearum</i> strains, and bacterial cell numbers were counted by grinding and dilution plating tubers at different times after inoculation. The experiment was repeated three times, with three tubers per strain per time point. At 6, 9 and 12 weeks after inoculation, the population sizes of UW551ΔlecM and UW551ΔaidC in tubers were significantly lower than those of the wild type parent strain (<i>P</i><0.05, ANOVA).