Development of Potato Late Blight Epidemics: Disease Foci, Disease Gradients, and Infection Sources

Urban Farm DB summary

A study in Southern Flevoland, Netherlands, from 1994 to 1996, assessed inoculum sources of potato late blight. It found that 74% of early disease foci in commercial potato fields were linked to nearby infested refuse piles. Infected seed tubers, volunteer plants, and infested allotment gardens appeared to be of minor importance for late blight development in potato fields. However, in August 1994, infested organic potato fields became major mid-season infection sources, spreading the disease to adjacent conventional fields.