Next, she plans to identify its genotype and track its historic route of migration around the world. She has devised new diagnostic tools, using recombinant DNA techniques, that allow more rapid and accurate detection of the pathogen s presence in potatoes before they are stored or planted. NC State has been issued a patent on Ristaino s technique. Her research collaborators are Greg Parra of NC State and Dr. Carol Trout Groves, a former NC State postdoctoral fellow now at the USDA Agricultural Research Service s New England Plant, Soil and Water Laboratory in Orono, Maine. Their study is funded in part by the National Geographic Society.
Potatoes are one of the world s four leading food crops, along with rice, maize and wheat.
Late blight poses an especially great threat to potatoes in developing countries, where control measures may be too costly to use. We re excited about our results and believe these kinds of studies of epidemics could be constructed for a range of plant pathogens. Late blight epidemics caused by Phytophthora infestans led to the Irish potato famine in the 1840s. Protocols for DNA extraction and PCR amplification were optimized using modern herbarium specimens. Various modifications of a CTAB extraction protocol including column purification and ethanol precipitation were effective for obtaining PCR quality DNA from herbarium specimens.