Cryphonectria parasitica (Syn. Endothia parasitica),
the causal agent of chestnut blight, is a fungal pathogen of Castanea
and to a minor extent on Quercus species. In Europe this
disease lost its severity due to the natural spread of the dsRNA
hypovirus
CHV1. This hypovirus can be transmitted through hyphal anastomosis,
resulting in conversion of the recipient strain to the hypovirulent
phenotype (in vitro
demonstration of transmissible hypovirulence). Transmission of the
hypovirus is limited by a vegetative incompatibility system in C.
parasitica.
Analysis of the fungal population structure (vc type diversity, sexual
and asexual reproduction) and of the diversity of the hypovirus will
yield information on the dispersal and establishment of hypovirulence
as well as on introduction pathways. This provides the basis for
biocontrol measures.
| Chestnut blight cankers on Castanea sativa | |
| |
|
| Active canker. Bark cracks and epicormic shoots below the canker. | Superficial, non-lethal canker after natural infection with hypovirulent C. parasitica strains. |
List of European VC
tester
strains