About Neonectria ditissima (Tul. & C.Tul.) Samuels & Rossman
Neonectria ditissima, also known by the synonym Neonectria galligena, is a fungal plant pathogen. It causes cankers that can kill tree branches by restricting flow through vascular tissue. Two tree species known to be susceptible to this pathogen are apple and beech trees.
The host range of Neonectria ditissima includes many different hardwood tree species, including species from the genera Fagus, Populus, Salix, Betula, and Acer. Populations of these host tree species occur in both North America and Europe. Phylogenetic studies have found genetic divergence between the North American and European populations of Neonectria ditissima at specific loci: ß-tubulin and RPB2. Because American populations of the fungus have high levels of within-population genetic diversity, researchers have hypothesized that North America is the place of origin for N. ditissima.
