Do spittlebugs feed on grape? Assessing transmission potential for <i>Xylella fastidiosa</i>

Abstract

The bacterium Xylella fastidiosa is a causal agent of Pierce’s disease in grapevines and is considered to be vectored by several xylem-feeding insects. Xylella fastidiosa and its primary insect vector Homalodisca vitripennis are not currently present in New Zealand, but considered a biosecurity threat to the wine industry. Should it be introduced, infection and dispersal of X. fastidiosa within New Zealand vineyards could occur through extant vectors, especially spittlebugs. Electrical Penetration Graph technology was used to compare the feeding behaviour of three spittlebug species (Philaenus spumarius, Carystoterpa fingens and Carystoterpa minor) on grape (Vitis vinifera Sauvignon blanc) and their original host plants. Results suggest that Philaenus spumarius feeds on grape more than the other two spittlebug species. As Philaenus spumarius has been reported as a vector of X. fastidiosa, their potential to transmit the bacterium into grapevines is discussed based on the real feeding times recorded by EPG.