Differing Responses To Cryphonectria Parasitica At Two Indiana Locations

Chestnut blight, a disease that has spread rampantly among American (Castanea dentata (Marsh.) Borkh.) and European chestnut (C. sativa Mill.) trees, results from infection by the fungal pathogen Cryphonectria parasitica (Murrill) M.E. Barr (C. parasitica). This fungus was introduced in the early 1900s and has almost functionally eliminated chestnut trees from the North American landscape. In 2017, we collected chestnut blight samples from two sites (Site B, (Fulton Co., IN) and Site C (Marshall Co., IN)). At the Fulton County planting, Site B, cankers had formed, healed over, and the trees were healthy. However, at the second site in Marshall County, (Site C), cankers continued to propagate until all of the chestnut trees had died back to the ground. Research evidence worldwide has indicated that these visual clues likely result from the presence of a hypovirus. Upon closer inspection and the subsequent isolation and reproduction of spores, no hypovirus has been identified from either site. Here, we present a curious coincidence where one site has completely succumbed to the disease, while the other has been able to spring back to health.