Michael Bradshaw’s lab and co-author Ignazio Carbone published a PNAS paper that pinpoints the ancestral history of powdery mildew disease. Genetic testing and molecular clock techniques revealed evidence that pathogens causing powdery mildew disease can jump from a native plant to a newly introduced plant. In North American samples, the powdery mildew Podosphaera shepherdiae infects strawberries, while in Europe and Asia a related powdery mildew, Podosphaera fragariae, plagues strawberries. This study also showed that these two powdery mildew pathogens affecting strawberries on different continents split off from each other more than five million years ago. Read more about this exciting research in the press release HERE.