Wild Potatoes Reveal Resistance

Posted by Matt Hopkins|16 June 2010

MADISON, Wisconsin, US — Agricultural Research Service (ARS) scientists at the ARS Vegetable Crops Research Unit in Madison, Wisconsin have identified a species of wild potato that could help protect cultivated potato crops against disease. Germplasm from the resistant wild potato species, Solanum verrucosum, contains a gene with resistance to late blight, which is considered the most destructive potato disease. ARS scientists are
working to move the late-blight resistance gene from S. verrucosum into cultivated potatoes to create a potato that’s resistant to both late blight and early blight.

The multi-disease-resistant cultivar was created by crossing S. verrucosum with an early-blight resistant wild potato species, then crossing that hybrid with cultivated potatoes. The resulting seedlings created in the greenhouse are now awaiting field tests.

Another wild potato species, Solanum chacoense, has been found to have resistance to Verticillium wilt, a fungal disease that can remain in the soil for up to 10 years. The scientists crossed S. chacoense with cultivated potatoes, producing what a lead scientist called “a good, durable gene that may hold up over the long term.”

The studies have been published in Physiological and Molecular Plant Pathology, Molecular Breeding and the American Journal of Potato Research; more information is available in the May/June 2010 issue of Agricultural Research magazine.