The primary purpose of this agreement is to enhance citrus germplasm mobility between california and florida by developing and validating diagnostic assays for graft-transmissible citrus pathogens

Award Overview

The Regents of the University of California at Riverside received a Cooperative Agreement of $165,473 from the Animal and Plant Health Inspection Service (APHIS) under the Plant and Animal Disease, Pest Control, and Animal Care program (CFDA 10.025). The award, effective September 1, 2025, through August 31, 2026, aims to enhance citrus germplasm mobility between California and Florida by developing and validating standardized diagnostic assays for graft-transmissible citrus pathogens.

Products and Services Delivered

UC Riverside will design and validate singleplex and multiplex quantitative polymerase chain reaction (qPCR) assays targeting eight viruses, three phytoplasmas, and four fungi that impede citrus germplasm exchange. The institution will develop in-house validated diagnostic tools and share them with other U.S. citrus diagnostic laboratories to compare assay performance and reproducibility. By standardizing these diagnostic tools, the project directly addresses inefficiencies caused by repeated therapy, testing delays, and increased costs associated with current germplasm movement protocols. The validated assays will facilitate safe and efficient exchange of citrus germplasm between Florida and California, ultimately providing U.S. citrus producers with quicker access to new varieties from other states while ensuring the health and quality of exchanged germplasm.

The lack of standardized diagnostic assays hinders the movement of citrus germplasm, resulting in repeated therapy and testing, delays, and increased costs. The project will standardize diagnostic tools to facilitate the safe and efficient movement of citrus germplasm between california and florida, supporting research and industry needs by ensuring the health and quality of exchanged germplasm. This project will develop and validate standardized diagnostic assays for graft-transmissible citrus pathogens, specifically designing and validating singleplex and multiplex qpcr assays targeting 8 viruses, 3 phytoplasmas, and 4 fungi, to facilitate the safe and efficient exchange of citrus germplasm between florida and california. Our in-house validated diagnostic assays will be shared with other U.S. Citrus diagnostic labs to compare assay performance and reproducibility. Results of this project will benefit U.S. Citrus producers by providing quicker access to new varieties from other states.