Diaporthe vaccinii detected again in the Netherlands
In the Netherlands, the presence of Diaporthe vaccinii (EPPO A2 List) was noticed for the first time in 2006 (EPPO RS 2009/130). The fungus was detected on 1 plant of highbush blueberry (Vaccinium corymbosum) in Horst, province of Limburg. As the plant was destroyed and the fungus was not detected in any other plants during subsequent surveys, it was considered that D. vaccinii no longer occurred. However, during recent follow-up surveys, symptoms of fungal damage on twigs were observed in May 2011 in another V. corymbosum production facility located in the same area (America-Horst, province of Limburg). No impact on yield was recorded at the affected company. In June 2011, similar symptoms were also observed on blueberries (V. myrtillus) in a moorland forest (Planken Wambuis) near Ede, province of Gelderland. The identification of D. vaccinii is complex but the fungus could be identified on the basis of morphological characteristics of pycnidia, conidia and aspect of the colonies growing on agar media, followed by a molecular test (DNA sequencing). It is considered that the regular imports of Vaccinium plants for plantings from North America (where the fungus occurs) constitute a likely pathway of introduction. It is not the first time that D. vaccinii is detected in the EPPO region, as several countries (Germany, Lithuania, Romania and the United Kingdom) have reported findings of this fungus which were subsequently eradicated. In 2013, surveys will be conducted at Vaccinium production sites and in public greens to better determine the distribution of D. vaccinii in the Netherlands. The infected plants will be destroyed.
The pest status of Diaporthe vaccinii in the Netherlands is officially declared as: Transient, under surveillance.
Sources
NPPO of the Netherlands (2013-04).