XYL-SPIT · Understanding the relationship between Xylella fastidiosa and the meadow spittlebug Philaenus spumarius for a sustainable bacterial-mediated diseases control

Research on sustainable containment strategies of diseases caused by the vector-borne bacterium Xylella fastidiosa is hampered by the lack of knowledge on key elements of vector-host-bacterium intimate interaction. Moreover, available data on this three-way relationship come from studies carried out with sharpshooters, the main American bacterial vectors. On the other side, nothing is known on the insect family who likely plays the major role in bacterium epidemiology in Europe, i.e. spittlebugs, to which Philaenus spumarius, the main vector of X. fastidiosa to olive in South Italy, belongs to. The main objective of this project is to thoroughly characterize P. spumarius-X. fastidiosa relationship and transmission dynamics through a multidisciplinary approach, combining real-time tracking of insect probing behavior, classical transmission tests and microscopy. First, we are going to characterize the spittlebug acquisition/inoculation behaviors of the bacterium on different host plant/bacterium strain combinations. Once these behaviors have been characterized, we will determine the sites within spittlebug foregut where bacterial cells are retained suddenly after acquisition, and from where the cells are detached and delivered to the host plant during inoculation. Finally, we will focus on P. spumarius behavior on, and X. fastidiosa transmission dynamic to, olive varieties found to be tolerant to the bacterium. The results of the present project will represent an essential step toward the set-up of a sustainable bacterium-mediated diseases containment strategy. This fellowship represents a unique opportunity for the applicant. The experience gained from this three-year multidisciplinary project will make Daniele Cornara a serious candidate for an academic position throughout Europe, beside an important resource for Europe considering the threat posed by the relentless spread of X. fastidiosa throughout the Continent.