Ralstonia solanacearum detected in ware potatoes in Belgium
The NPPO of Belgium recently informed the EPPO Secretariat that during the official annual survey on potato brown rot, one batch of ware potatoes (Solanum tuberosum cv. ‘Fontane’) in storage was found to be latently infected by Ralstonia solanacearum (EPPO A2 List). On 2015-02-09, 1 sample of 200 tubers was taken at random in a warehouse. On 2015-03-05, a suspicion of infection was notified to the NPPO and on 2015-03-11, the identity of the bacterium was officially confirmed. In accordance with the EU Directive 98/57/EC, the screening test involved isolation on SMSA medium and PCR, and the final confirmation was obtained by a biotest. As a consequence of this detection, an infected area of 4.8 ha was demarcated in Bocholt (province of Limburg). The origin of the infection is not yet known, but contamination by surface water (irrigation water used during the previous cropping season or water used for spraying pesticides) is suspected because the plot is located close to an area covering 44 municipalities where contaminated water courses are known to occur. However, in the near vicinity of the demarcated area, watercourses are not known to be contaminated by R. solanacearum and no Solanum dulcamara plants were found in them. In these watercourses, further sampling of water is planned during summer 2015 to verify the possible presence of R. solanacearum. Official phytosanitary measures have been taken to eradicate the disease. These measures included a treatment of the infected potato lot (under quarantine conditions and carried out in a Dutch feed processing unit), and implementation in the infected field of the measures provided by the EU Directive 98/57/EC.
The official pest status of Ralstonia solanacearum in Belgium is officially declared as: Present, in a few water courses in the provinces of Antwerpen and Limburg (44 communes), subject to official control and one outbreak in ware potatoes under eradication.
NPPO of Belgium (2015-07).