Xylella fastidiosa (Xf) and its New Zealand vectors

This research will deliver critical, currently unavailable, knowledge on the distribution of potential endemic spittlebug vectors of Xylella fastidiosa (Xf), their ecology, host plants, seasonality, and movement between the native and productive estate.

The information will be incorporated into MPI and DOC Xf risk assessments for the productive and native estate and industry response plans through the Xylella Action Group (XAG). This will have short and long-term benefits for New Zealand’s biosecurity system; e.g., where to concentrate early detection surveillance efforts, or manage imports of certain plant species for a more efficient response to a potential Xf incursion. This will allow for a cross-sector collaborative approach to preparation and response should an incursion take place.

The field research has indicated that the exotic Philaenus spumarius (meadow spittlebug), a known vector of Xf in Europe, is widespread in New Zealand, and that the endemic spittlebugs are hard to find in the fragmented productive landscapes. We have also explored citizen science activities in 2022-2023 to obtain spittlebugs from regions we were not addressing with our research. The spittlebug species collected in the different activities have been used to develop a molecular diagnostic tool for identification to support the taxonomic key from 1992.

The data generated by the structured and opportunistic entomological field research in selected areas in New Zealand in the 2020-2023 seasons, along with any existing data, is now used to model both national scale habitat and spittlebug distribution scenarios. Spatially explicit, mechanistic simulation modelling using field data from contrasting landscapes is used to explore various transmission rates and understand risk profiles.

Contact Project Leader Jessica Vereijssen: [email protected]