Survival of Ralstonia solanacearum on wood,high density polyethylene and on jute fabric in cold storage

Containers used for the transport and storage of potatoes in the warehouse may be contaminated by Ralstonia solanacearum cells and become sources of inoculum and the means of spreading infection over short, medium and long distances. The materials of which the containers are made could be an important factor influencing the survival of contaminating bacteria. This paper describes the study of survival of R. solanacearum in cold storage at 4C° on poplar and oak wood, on high density polyethylene and on jute sack fabric. Survival was quantitatively assessed on the final concentrates, obtained by washing samples of contaminated materials and centrifuging the washing liquids. The plate count was performed on two semi-selective media (Kelman’s and SMSA). Survival on wood was found up to approximately 4 (oak) and 17 days (poplar) after contamination. On high density polyethylene survival was zero after 2 days. On jute fabric, the number of contaminating bacteria, dropped considerably after 24 hours, but subsequently the decrease was moderate and the population was only zero after 78-108 days. The regression curves are presented for the experimental data together with the survival percentages.