TaqMan real-time PCR method for detection of Discula destructiva that causes dogwood anthracnose in Europe and North America

Dogwood anthracnose, caused by the asexual filamentous fungus Discula destructiva Redlin, is a disease of several Cornus L. species. First reported in the 1970s in the United States, the pathogen has devastated North American dogwood populations causing widespread loss that has greatly impacted forest ecosystems. In the early 2000s, the disease was discovered in Italy and Germany, spread probably through the ornamental nursery trade. The origin of D. destructiva in North America remains a mystery. To facilitate studies on its origin and dispersal, a fast and accurate method using real-time PCR was developed in this study to detect and quantify D. destructiva. The assay was validated with samples from the U.S., Italy, and Switzerland as well as phylogenetically closely related fungal species, and other fungi and oomycetes commonly found on Cornus. This method allows for fast and sensitive detection of D. destructiva in host tissue and should be useful in disease management and pest interception to prevent further spread of the pathogen.