Ring rot (Clavibacter michiganensis subsp. sepedonicus) and brown rot (Ralstonia solanacearum) of the potato are both bacterial diseases which have not been detected in Switzerland so far. Samples of potato imports and Swiss seed potatoes are tested every year. Out of about 500 lots 200 tubers of each lot are analysed in our laboratory.

Should one of these two bacterial species be detected one day, the source of infection must be immediately identified. In order to do that, lots that have been somehow "related" or have come into contact with the infected one must be thoroughly sampled and analysed. Lots and plots suspected of being affected by the pest will be temporarily blocked, and if the infestation has been confirmed lots must be destroyed and plots banned from potato production altogether.