D3513: Risk-based commercial citrus survey for HLB/ACP in San Joaquin Valley, California

Several invasive citrus pests have been detected in California, including Asian Citrus Psyllid (since 2008), Huanglongbing (HLB) (since 2012), Citrus yellow vein clearing virus (since 2022), Tau fruit fly (in 2023) and sweet orange scab (since 2013). These pests and diseases threaten fresh fruit production and export, causing major concern to the commercial citrus growers in the San Joaquin Valley (SJV). A standardized surveillance methodology will ensure informed decision-making and optimized resource allocation. Given HLB and its vector ACP have not yet established in SJV, where majority of California citrus is located, a comprehensive surveillance methodology targeting ACP and HLB in valley will be pivotal in early detection and eradication of the vector and pathogen. The NCSU epidemiologist (Dr Luo) with RBS expertise and a grower-funded boots-on-the-ground program (Alliance of Pest Control Districts-APCD) is aptly positioned to develop and implement RBS methodology for multiple pests and diseases. In the current project, APCD provided basic data related to commercial citrus for developing the RBS model. Dr Luo developed a preliminary risk assessment model incorporating factors such as international travel data, historical pest/disease prevalence, potential spread vectors, and biological traits. APCD is currently carry out the surveillance using the RBS model. Dr. Luo will validate the RBS model using the newly acquired surveillance data. Such an epidemiological model will act as the first line of defense against invasive and exotic citrus pests and diseases across citrus industries in multiple states.