Occurrence of artichoke-infecting viruses in Tunisia

Crops of globe artichoke (Cynara scolymus) in Manouba and Bizerte regions, Tunisia, were surveyed in spring and autumn 2012 for the presence of key artichoke viruses. A total of 336 leaf samples were collected randomly from plants that were either asymptomatic or showing virus-like symptoms. These were tested for Artichoke Italian latent virus (AILV), Cucumber mosaic virus (CMV), Artichoke mottled crinkle virus (AMCV), Pelargonium zonate spot virus (PZSV), Artichoke latent virus (ArLV), Bean yellow mosaic virus (BYMV), Turnip mosaic virus (TuMV), Potato virus X (PVX), Tomato infectious chlorosis virus (TICV) and Tomato spotted wilt virus (TSWV). Results from dot-blot hybridization and reverse transcription polymerase chain reaction (RT-PCR) showed the occurrence of AILV and BYMV for the first time in Tunisia, and confirmed that of TICV on artichoke crops. ArLV and AILV were the most frequent viruses detected, whereas infections of AMCV, CMV and PVX had a lower incidence. PZSV, TuMV and TSWV were not detected in any of the samples collected. Notable differences were observed between results from spring and autumn surveys, probably as a consequence of the different vegetatives status of the plants and different leaf sample conditions (fresh versus dried). Consequences of the import of planting material with a poor sanitary status and of the overall phytosanitary status of globe artichoke in Tunisia are discussed.