First report of Eutypella parasitica in Germany and updated situation in Austria
During studies conducted from 2013 to 2015, Eutypella parasitica (formerly EPPO Alert List) was detected for the first time in Germany. The fungus was detected on 105 maple trees (Acer pseudoplatanus, A. campestre, A. platanoides, A. cappadocicum, A. heldreichii subsp. trautvetteri and A. hyrcanum) in Munich (Bayern). Affected trees were located in urban forests (78 trees), urban green areas (20 trees) and private gardens (7 trees). The majority of infected trees (74) occurred on sites adjacent to water bodies (a river, ponds or small lakes), with high air humidity during most of the year. The maximum distance between localities with Eutypella canker was about 15 km. E. parasitica is native to the USA and Canada and causes perennial cankers and wood decay on several species of maple. In the EPPO region, E. parasitica was first recorded in Slovenia (EPPO RS 2005/176) and then in Croatia (EPPO RS 2008/028), Austria (EPPO RS 2007/051), Czech Republic (EPPO RS 2015/210) and Hungary (EPPO RS 2016/108).
In Austria, since the initial finding of E. parasitica in 1 forest site near St. Veit an der Gölsen (Niederösterreich) on 5 A. pseudoplatanus trees, additional surveys have been conducted. In July 2011, characteristic symptoms of Eutypella cankers were observed in the gardens of the Traunsee castle in Altmünster (Oberösterreich) on 2 A. pseudoplatanus trees. Considering the rather wide distribution of the pathogen in the EPPO region and the fact that many occurrences have probably not yet been detected, eradication is not considered feasible. However, it is desirable to prevent any further spread of the disease and several management measures might be recommended such as, destruction of diseased trees with careful disposal of infected plant material, surgery on valuable individual trees (e.g. by cutting a narrow area of bark around the canker margins), growing conditions minimizing spore dispersal.
Sources
Cech TL, Schwanda K, Klosterhuber M, Straßer L, Kirisits T (2016) Eutypella canker of maple: first report from Germany and situation in Austria. Forest Pathology 46, 336–340. doi:10.1111/efp.12268