Longevity ofPseudomonas solanacearum in potato tubers and culture in cold storage

Abstract

Potato tubers naturally infected withP. solanacearum were stored at 35 F. At various intervals, infected tubers were assayed for the presence of virulent and viable bacteria. In addition, 4 virulent bacterial isolates derived from infected potato tubers were stored at 35, 55, and 75 F. The bacteria lost their virulence and viability in tubers and in culture when stored at 35 F. The bacteria in a few infected tubers survived 7 months but not ten months storage; whereas, bacteria in culture lost their viability more quickly (134 and 171 days). The same bacterial isolates stored at 55 F were still highly virulent after 171 days. The isolates differed in their response to the cold temperature treatment. The subcultures of only one isolate were virulent after 134 days storage. All isolates were nonviable after 171 days storage.