Skip to main content
ARS Home » Pacific West Area » Corvallis, Oregon » Horticultural Crops Disease and Pest Management Research Unit » Research » Research Project #443229

Research Project: Detection of Phytophthora Infections in West Coast Nurseries

Location: Horticultural Crops Disease and Pest Management Research Unit

Project Number: 2072-22000-046-029-S
Project Type: Non-Assistance Cooperative Agreement

Start Date: Sep 1, 2022
End Date: Jun 1, 2027

1. To develop and refine Phytophthora detection and identification methods for the nursery industry. 2. To monitor fungi and oomycetes present in native and large-scale ornamental nurseries and assess species pathogenicity and environmental conditions favoring disease.

This research will develop and refine rapid, low cost detection and identification methods for Phytophthora species affecting the nursery industry. Monitor fungi and oomycetes present on ornamental plants in nurseries using traditional isolation and molecular methods. Years 1-2: Laboratory experiments will be conducted to develop and optimize existing temperature independent recombinase polymerase amplification (RPA) methods for detecting Phytophthora species affecting West Coast (California and Oregon) nursery crops. This assay will consist of two steps: 1) Validate the efficacy of the RPA assay using the TrnM marker, and develop a Phytophthora species specific identification method based on a nested PCR (atp9-nad9) region and sanger sequencing. Years 3-5: Detection and identification methods will be validated using inoculated plants from greenhouse and field experiments, as well as from plant samples collected during nursery surveys for Phytophthora root rot. Detection methods will be refined based on results from validation assays to ensure that the widest possible range of Phytophthora species are detected.