A FIVE-YEAR SURVEY IN TUSCANY (ITALY) AND DETECTION OF XYLELLA FASTIDIOSA SUBSPECIES MULTIPLEX IN POTENTIAL INSECT VECTORS, COLLECTED IN MONTE ARGENTARIO

The vector-borne bacterium Xylella fastidiosa (Wells and Raju) causes several serious diseases to plants. Recently, different subspecies of X fastidiosa were reported in some European countries. The risk of the bacterium's spread on the entire European territory is very high; therefore, it has been added into the priority pest list (2019/1702/EU Regulation). The main purposes of this work were to verify the presence of potential vectors in areas at a high risk of introduction in Tuscany and to ascertain the presence of X. fastidiosa in these insect vectors. Over 4,000 Auchenorrhyncha were collected and analysed from 2015 to 2019. Among the xylem sap-feeder putative vectors, most of the insects collected belonged to the family Aphrophoridae, but also many species of leafhopper were identified. Overall, in Tuscany four species were the most represented: Philaenus spumarius (L.), Cicadella viridis (L.), Synophropsis lauri (Horvath) and Neophilaenus campestris (Fallen). In 2018 an outbreak of X. fastidiosa subsp. multiplex was reported in Monte Argentario (Grosseto province, Tuscany). In 2019 X. fastidiosa subspecies multiplex ST 87 was detected in seven P. spumarius and three N. campestris collected from the infected area.