Phytosanitary incident: Clavibacter michiganensis subsp. sepedonicus found in imported potatoes in Finland
In Finland, in March and April 2000, 3 seed potato lots (Solanum tuberosum cv. Velox) were imported from Germany and tested negative for Clavibacter michiganensis subsp. sepedonicus (EPPO A2 quarantine pest) by immunofluoresence assay (IFA). During summer 2000, these lots were then cultivated in 3 Finnish farms. In November 2000, one tuber showing visual symptoms of potato ring rot was observed in 1 farm. The tuber was tested by IFA and PCR and gave positive results. All other seed lots were immediately tested and contaminations were found in all lots of potatoes cv. Velox cultivated in the 3 farms concerned. These farms are specialized in seed potato production. For several years, they have only been cultivating officially inspected seed potatoes, and their whole potato production has yearly been tested for latent infections. Until this incident, the disease had never been found. It was concluded that the only possible source of infestation was the import of infected seed potatoes from Germany. According to Directive 93/85/EEC, strict eradication measures are being applied.
NPPO of Finland, 2001-02.