摘要：In the vegetation period 2009 Hymenoscyphus
albidus, the sexual stage of the ash dieback pathogen
Chalara fraxinea, was recorded at numerous sites in
five Federal Provinces of Austria. Apothecia of this
ascomycete fungus were regularly and frequently
found on leaf petioles and rachises of Fraxinus excelsior
from the previous year in the litter. Records of
H. albidus in the database of fungi in Austria indicate
that the fungus was rare in the past, but has become
more frequent since 2006. Based on the discovery of
H. albidus as sexual stage of C. fraxinea we present
the current state of knowledge about this emerging
tree disease and suggest a hypothetical disease cycle
of ash dieback.
