Identifying Biocontrol Agents for X-Disease Vectors to Allow Integrated Pest Management in Cherries: Progress Report

This BIOAg progress report documents development of molecular tools to identify biological control agents attacking X-disease leafhopper vectors in Pacific Northwest cherry systems. X-disease, also known as little cherry disease, is managed primarily through tree removal and chemical suppression of vectors. Limited knowledge of natural enemies has constrained integrated pest management (IPM) approaches.

The project validated primers for two key natural enemies, a parasitic fly (Tomosvaryella lepidipes) and a Hirsutella fungal associate, and advanced development of primers for a Dryinid parasitic wasp. Researchers also created species-specific primers and a two-step multiplex qPCR assay to distinguish vector species and detect phytoplasma infection. Field sampling across multiple orchards and regions generated more than 2,000 leafhopper specimens for screening.

This work establishes foundational diagnostics needed to quantify parasitism rates and evaluate the potential for incorporating biological control into X-disease IPM programs.