Distribution of regulated viruses in cv. Sangiovese vineyards in Tuscany

RT-real time PCR was used for the detection of 13 viruses in 768 samples of Vitis vinifera cv. Sangiovese collected from nine Tuscanian districts (Italy). Analysis of virus distribution was carried out on 482 samples infected with viruses responsible for infectious degeneration or associated with leafroll, fleck and rugose wood diseases that are included in the European (2005/43/EC) and Italian (DM 07/07/2006 and DM 24/06/2008) directives. Viruses associated with rugose wood disease were the most common (90%), Grapevine rupestris stem pitting-associated virus, which is not regulated, was found in more than 80% of infected samples, and Grapevine leafroll-associated virus 3 was the most frequent among EU-regulated viruses followed by Grapevine fleck virus. Grapevine virus A, a virus regulated in Italy, was found in more than 30% of infected vines whereas the presence of other non-regulated viruses such as Grapevine virus D (4%), Grapevine leafroll-associated virus 4 (GLRaV-4), GLRaV-4 strains 5 and 9 was low (1%). These findings indicate the need of implementing the European regulation for the production of high quality planting material.