Blueberry scorch virus: a new disease for highbush blueberry in Trentino

Blueberry scorch virus (BlScV) is a dangerous disease for blueberry orchards, causing damages and yield losses in North America. In 2004, it has been found in open fields in Europe (in Piedmont, North-west of Italy). Symptom expression varies according to the blueberry cultivar and the virus strain. Susceptible varieties usually show a rapid flower and twig blight (scorch). During the summer 2009, some highbush blueberry (Vaccinium corymbosum) plants grown in Trentino Province (North-eastern Italy) showed symptoms usually associated to BlScV and a number of samples tested positive in specific DAS-ELISA for BlScV. In 2010, the presence of the virus was confirmed on V. corymbosum and it was also identified on V. ashei. Sequence analysis of the coat protein coding region demonstrated that the strain isolated in Trentino was distinct from the strain previously identified in Piedmont and most similar to strains from Washington State (USA). Control and prophylactic measures were carried out.