Presence, diversity and seasonal fluctuation of Xylella fastidiosa potential vectors and other Auchenorrhyncha (Hemiptera) in olive agroecosystems with different management systems

Presence, seasonal abundance and diversity of Xylella fastidiosa potential vectors species and other Auchenorrhyncha were studied in olive orchards under different management systems. Auchenorrhyncha were monitored monthly in 6 olive groves at Istiea (Central Greece) and Chania (South Greece) for 13 months using Malaise traps and sweeping-net, as a sampling strategy to collect even the most, or the least-mobile Auchenorrhyncha within the orchards. The most abundant X. fastidiosa potential vector was Philaenus spumarius , followed by Neophilaenus campestris, Cercopis sanguinolenta, Lepyronia coleoptrata and Neophilaenus lineatus. Olive orchards in Chania had a lower abundance and diversity in X. fastidiosa potential vectors, as well as in total Auchenorrhyncha. The abandoned olive orchard hosted the highest population of potential vectors in Chania, but the lowest in Istiea, compared with the respective cultivated one. The organic farms were more diverse in Auchenorrhyncha compared to the other management systems in both regions. Weed control provided the most probable explanation for the significant Auchenorrhyncha population fluctuation among olive orchards. However, insecticide applications against olive fruit fly did not affect Auchenorrhyncha abundance. The conventional orchard in Istiea displayed the highest abundance and species richness of the potential vectors of X. fastidiosa, mainly during autumn, when dried weeds remained in the orchard after herbicide application. Regarding monitoring methods, sweeping-net was the method with the most abundant potential vector collection in general, while Malaise traps were more efficient for collecting potential vectors during migration to the dried weeds (in fall).GR; PPT; atsagarakis@aua.g