Topic summary
Cryphonectria parasitica
Extracted from the Wikipedia article Chestnut blight.
Overview
Cryphonectria parasitica is a parasiticfungus of chestnut trees. This disease came to be known as chestnut blight. Naturally found in Southeast Asia, accidental introductions led to invasive populations of C. parasitica in North America and Europe. In the first half of the 20th century, the fungal disease had a devastating economic and social impact on communities in the eastern United States. It killed an estimated four billion trees; or, by another count, 3.5 billion trees through 2013. Less severe impacts have occurred in Europe due to widespread CHV1-induced hypovirulence. CHV1 is one of at least two viral pathogens that weaken the fungus through hypovirulence and helps trees survive a blight infection.