Chestnut Blight: Biological Control by Transmissible Hypovirulence in <i>Endothia parasitica</i>

Abstract

Hypovirulence in Endothia parasitica is caused by a cytoplasmic determinant that is transferred by hyphal anastomosis in host tissue and in culture. Transmission of this determinant affects the virulence of the fungus to the extent that host invasion by previously virulent isolates is limited.