Occurrence and distribution of Scaphoideus titanus in multiple outbreaks of "flavescence dorée" in Serbia

A total of 23 viticultural regions in Serbia were surveyed from 2004 to 2006 to determine the occurrence and distribution of Scaphoideus titanus, vector of grapevine phytoplasma “flavescence doree”. Grapevine samples from over 600 plants showing suspected symptoms of phytoplasma infection, were collected from all surveyed regions for subsequent molecular identification and determination of FD incidence. Presence of S. titanus was surveyed in all areas and collected samples were analyzed with PCR/RFLP for FD presence confirmation. With exception of southern region of Pcinja, S. titanus was detected in all surveyed regions, including areas close to Croatian, Hungarian, Romanian and Bulgarian state borders. Significant populations of this leafhopper were recorded in vineyards, as well as, on wild Vitis plants, showing wide distribution of this species in Serbia. FD phytoplasma was registered both, in vector and in grapevine in 8 regions and its presence was correlated with high density of S. titanus populations in surveyed vineyards. Incidence of symptomatic plants in vineyards ranged from 10 to 100% in most endangered regions, while infestation level of S. titanus with FD ranged from 12.5 to 45%.