D3289: Pathogen prevalence in Circulifer tenellus collected in the Columbia Basin of Washington State using novel insect extraction and PCR protocols

The Columbia Basin of Washington is home to a variety of vegetable and seed crops, including potato, carrot, bean, radish seed, sugar beet seed, and coriander seed, that are affected by beet leafhopper (Circulifer tenellus)-transmitted pathogens each year. These pathogens include Beet curly top virus, Beet leafhopper transmitted virescence agent phytoplasma, and Spiroplasma citri; all of which have been associated with serious economic losses in different crops throughout the Columbia Basin since the early 2000s. To provide near real-time beet leafhopper-associated pathogen data to growers for incorporation into their insect pest management programs, a high-throughput 96-well nucleic acid extraction method and novel pathogen detection methods (including a multiplex qualitative real-time polymerase chain reaction assay) were designed. These tools enabled the rapid analysis of weekly beet leafhopper specimens, which were incorporated into the Washington State University online Potato Decision Aid System for dissemination of results to growers, beginning in 2022. Analysis of pathogen prevalence in beet leafhopper specimens captured from 2021-2023 identified seasonal pathogen trends, as well as locations throughout the Columbia Basin with higher pathogen incidence. Pathogen prevalence was compared between beet leafhopper specimens captured near non-potato crops and those captured near potato, with higher Beet curly top virus levels in specimens captured near non-potato fields. These results from 2021-2023, coupled with near real-time dissemination of pathogen prevalence in beet leafhopper through the Decision Aid System each year, will enable growers across the Columbia Basin to make more informed decisions when controlling the beet leafhopper vector.