Molecular genetic determinants of intraspecific polymorphism of the phytopathogenic fungus Cryphonectria parasitica

The review summarizes the current evidence on the phytopathogenic fungus Cryphonectria parasitica, which is a classic object for studying hypovirulence. Phenotypic manifestations of hypovirulence and the molecular mechanisms of action of the mycovirus Cryphonectria hypovirus (CHV) infecting the fungus are described in detail. Genetic determinants of vegetative incompatibility in C. parasitica (a phenomenon increasing polymorphism of the fungus and preventing CHV expansion) are considered. The data on C. parasitica polymorphism are correlated with the data on the distribution of different CHV species in the European, American, and Asian populations of the fungus.