Location: Crop Improvement and Protection Research
Project Number: 2038-22000-020-029-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Nov 1, 2025
End Date: Jun 30, 2028
Objective:
1) Develop and optimize targeted diagnostics to detect multiple viruses in a single test sample;
2) Sample potential crop and non-crop hosts from low desert and Central Valley production areas;
3) Screen samples from Objective 2 using targeted diagnostics (all) and nontargeted high throughput sequencing (selected);
4) Develop risk assessments and cultural management recommendations tailored to specific production regions;
5) Communicate results to stakeholders and collect data on responses.
Approach:
ARS and the University of California-Riverside will coordinate efforts through this grant to develop improved methods for control of a growing complex of viruses affecting melon and other cucurbit production in the southwestern U.S., including California, Arizona, and Texas. ARS will advance the development of diagonostic tools using multi-target RT-PCR and quantitative RT-PCR to detect and quantify all major whitefly-transmitted viruses impacting cucurbit production in the region. This will benefit not only the Southwest, but the entire U.S. cucurbit industry as these viruses are problematic elsewhere as well. Both ARS and UCR will work toward identification of weed and non-cucurbit host plants that can serve as virus reservoirs using the detection methods developed through the project as well as existing methods for those viruses not currently detected by the multi-target methods currently available. Whitefly populations will be monitored in conjunction with crop development using leaf turns and other standard methods. Finally, management recommendations will be developed based on results of the above research to limit whitefly populations, reduce the abundance of weed reservoirs that can harbor viruses during non-crop seasons, and enhance cucurbit immunity toward virus infection. This should reduce the impact of the existing and growing virus complex and limit spread within and among regions.