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Sneaky disease: Potato seed infected with Dickeya, the ‘new blackleg’ in Canada

Image result for dickeya potatoPotato seed infected late in the season with Dickeya (‘new blackleg’ in Canada) usually does not show symptoms in the field before harvest nor in seed storages, experts say. This is because Dickeya requires high temperatures for the development of visible symptoms. The optimum temperature for Dickeya is above 25 degrees Celcius. By contrast, the ‘old blackleg’ (Pectobacterium) can develop at cool temperatures (8-10 C), and symptoms are usually visible when cutting seed. “I have two questions about Dickeya,” says Dr Eugenia Banks, Potato Specialist at the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) in Canada: “If dormant infection of Dickeya is suspected, could you incubate a sample of tubers at 25 C to 30 C so that tubers will show Dickeya symptoms in about two weeks? Are Dickeya lesions smelly? We all know how smelly the old blackleg is…” More