Landscape composition predicts distribution of Philaenus spumarius, vector of Xylella fastidiosa, in olive groves

The meadow spittlebug, Philaenus spumarius (Hemiptera: Aphrophoridae; Linnaeus, 1758) is considered the main vector in the ongoing X. fastidiosa outbreak in the olive groves of Southern Italy. Identifying the factors driving the occurrence of P. spumarius is of primary importance to determine X. fastidiosa infection risk in healthy olive groves. Here, we investigate the local and landscape factors shaping the occurrence of P. spumarius by conducting a large sampling in 182 olive groves across two years in the Abruzzo region (Southern Italy). At the landscape scale, high proportions of olive groves generally supported a higher presence of P. spumarius, whereas high cover of vineyards was found to negatively affect its presence. According to its dispersal ability, P. spumarius best responded to landscape processes at small spatial scale (125 m). At the local scale, higher elevation increased the probability of occurrence of P. spumarius while soil and pest management had no effect. Our findings suggest that the management of agricultural landscape mosaics can drive the spatial dynamics of P. spumarius. In particular, the landscape composition of the close surrounding of the olive groves may potentially influence the emergence probability of local X. fastidiosa epidemics.