Our Research

Epidemiology and Management of Phytophthora Diseases of Citrus in California

Project ID:


Principal Investigator:

James Adaskaveg

Principal Investigator Affiliation:

University of California, Riverside





Start Date:


Estimated Duration:

5 year(s)

Completed Date:


Annual Funding:


With resistance to mefenoxam present and with the recent detection of phosphite resistance in multiple Phytophthora spp. on citrus in California, this project has a high impact in developing new soil and foliar fungicide treatments to reduce Phytophthora root rot and fruit rot. Management of Phytophthora diseases of citrus is also important to ensure the successful trade with overseas markets where some species of Phytophthora (e.g., P. syringae and P. hibernalis) are quarantine pests. Thus, there is an immediate and long-term impact in managing Phytophthora diseases in nurseries and orchards as well as keeping trade open with important export markets. Multiple active ingredients with different modes of action are being evaluated as foliar- and soil-applied treatments in this project.