British Columbia (BC) contributes 34% of Canada’s fruit farm‑gate value and is the country’s leading producer of highbush blueberry (95%), raspberry (77%) and cherry (94%). Since 2018, fruit production in BC has declined by 8.5% due to unprecedented weather events and growing biological threats to crop health.  

Two major pathogens pose significant threats to BC’s fruit sector. The Pseudomonas syringae complex (Psc) causes substantial economic losses in highbush blueberry, raspberry, kiwifruit, cherry, grapes and several stone fruits across BC and other Canadian provinces. Phytophthora spp. is responsible for raspberry decline in BC, accounting for approximately 30% yield loss over the past 35 years, and causes root rot and wilt in highbush blueberry, strawberry and forest tree species. Diseases caused by both pathogens are difficult to manage, making accurate pathogen identification a critical first step for effective disease control. 

Current diagnostic methods are labor‑intensive, time‑consuming and often lack sufficient resolution to identify pathogens to the species level. In addition, the population diversity of Pseudomonas and Phytophthora species in BC and Canada is poorly understood, and it remains unclear whether the same species can infect multiple fruit crops. 

This project will address these gaps by generating high-quality sequence data from these pathogens and develop rapid and accurate PCR-based diagnostic tools. These tools will be implemented by the Plant Health Unit at the BC Ministry of Agriculture and Food to enable precise identification of Pseudomonas and Phytophthora strains and to support informed disease management decisions. 

The new diagnostic tests and genomic data will allow the Plant Health Lab to identify pathogens across multiple fruit crops much faster and provide timely guidance to growers. The data will also help researchers track how these diseases change and spread over time, including the emergence of more virulent strains, adaptation to new hosts or cultivars and resistance to chemical control measures.  

Overall, this project will reduce disease incidence and spread, strengthen the resilience of BC’s fruit production systems under changing climatic conditions and support the economic and social well‑being of agricultural communities.