Prevalence of Viruses Associated with Grapevine Rugose Wood Disease in Tunisia

Abstract

To assess the prevalence and the distribution of viruses associated with rugose wood (RW) disease in Tunisian grapevines, surveys were conducted in the main Tunisian grapevine growing areas. A total of 403 samples were collected including autochthonous and international table and wine grapes, and rootstocks. All samples were analyzed by RT-PCR for the presence of Grapevine virus A (GVA), Grapevine virus B (GVB), Grapevine virus D (GVD), Grapevine virus E (GVE), Grapevine virus F (GVF) and Grapevine rupestris stem pitting-associated virus (GRSPaV), using specific primers. Molecular analysis showed that 80.9% (326 / 403) of the tested samples were infected with at least one virus. GRSPaV was the most widespread virus (51.3%), followed by GVA (47.9%), GVD (31.5%), GVF (22.3%), GVB (17.8%), and finally GVE (7.2%). According to grapevines typology, wine grapes were the most infected (93.9%) vines, followed by table grapes (87.8%) and rootstocks (75.0%). Autochthonous grapevine varieties were the less infected (65.9%). This is the first study on RWassociated viruses in autochthonous grapevines and rootstocks and the first report on the presence of GVE and GVF in Tunisian vines