Sunday, August 7, 2022

Phytophthora Root and Crown Rot Update

UC Davis sponsored program - "Nursery Phytophthora Best Management Practices (NPBMPs) designed to exclude Phytophthora from nursery plants were developed to exclude Phytophthora from nursery plants were developed to address the need for clean planting stock in restoration projects.  A pilot program to implement the systematic use of the NPBMPs, Accreditation to Improve Restoration (AIR), was developed and started in 2018.  As of 2020, 13 northern California restoration nurseries have been evaluated, and five have met all the program requirements.  In 564 tests conducted over 4 years with a sensitive leachate baiting protocol, no Phytophthora was detected from over 20,000 nursery plants produced in compliance with the NPBMPs.  In comparison, Phytophthora was detected in 25% of tests conducted on partially compliant stock and in 71% of tests from nurseries following few or no NPBMPs." - Tedmund J. Swiecki et al.

CDFA Program on Best Management Practices (BMPs) for Nurseries - This program is part of the Nursery Certification Program of the California Department of Food and Agriculture (CDFA). The goal of this CDFA nursery certification program is to promote the use of BMPs to give nurseries a higher level of confidence that their operations are reducing the introduction and spread of diseases and pests.

Resources - California Oak Mortality Task Force

From the California Oak Mortality Task Force Report September 2016:  "First detection of Phytophthora quercina in the US, associated with outplanted Quercus lobata, valley oak – P. quercina was recently isolated from valley oaks (Quercus lobata) as part of an evaluation conducted by the Rizzo Lab (UC Davis) and Phytosphere Research on restoration sites managed by the Santa Clara Valley Water District...  It has been rated the # 1 Phytophthora species of concern for introduction into the US in a USDA Plant Epidemiology and Risk Analysis Laboratory (PERAL) report. P. tentaculata, recently found in association with multiple native plant species in CA native plant nurseries, was rated as # 5 on the same list."

No comments: