info@asev.org
530-753-3142
Viticulture – Measuring and Managing Vine Water Status Session
June 18, 2025 – 2:20 pm – 4:20 pm
Research Reports
Location: Portola Hotel, Monterey, California
Moderator:
To be announced
Speakers:
| 2:20 pm – 2:40 pm | To Shed or Not to Shed: Differentials responses of Cabernet Sauvignon and Malbec Vines to Drought-induced Leaf Shedding Caetano Albuquerque, California State University, Monterey Bay |
| 2:40 pm – 3:00 pm | Impact of Extra Irrigation During Heatwaves on the Performance of Cabernet Sauvignon and Riesling Vines Charles Obiero, Washington State University, Prosser |
| 3:00 pm – 3:20 pm | Drip Irrigation or Vine Cooling: Which is the Best Strategy for Heatwave Mitigation in Cabernet Sauvignon Pietro Previtali, GALLO, California |
| 3:20 pm – 3:40 pm | Rootstock Drought Tolerance or Vigor Control? A Quandary for Cool Climate Dry-farmed Vineyards Patricia Skinkis, Oregon State University, Corvallis |
| 3:40 pm – 4:00 pm | Evaluating Machine Learning for Spatial-Temporal Prediction of Grapevine Water Status Using Landsat 8 Imagery Luca Brillante, California State University, Fresno |
| 4:00 pm – 4:20 pm | Boosting Soil Water Retention and Vineyard Sustainability: The Impact of Biochar and Hydrogels Ashraf El-kereamy, University of California, Riverside |
Shijian Zhuang, Shunping Ding | Edgar Godoy Monterroso | Qun Sun | Matthew Fidelibus | Philippe Rolshausen
Field Application of Biofungicides to Control Powdery Mildew and Botrytis Bunch Rot on California Winegrapes
Shijian Zhuang, Shunping Ding,* Edgar Godoy Monterroso, Qun Sun, Matthew Fidelibus, and Philippe Rolshausen
*California Polytechnic State University-San Luis Obispo, 1 Grand Ave, San Luis Obispo, CA, 93407 (sding01@calpoly.edu)
Grapevine powdery mildew caused by Erysiphe necator and Botrytis bunch rot, caused by Botrytis cinerea, are the two of the most important fungal diseases for California grape production. Growers are increasingly interested in using biofungicides because of tightening state regulations and the development of fungicide resistance in fungal populations. We initiated biofungicide trials in 2023 in two CA regions: CA Central Coast (San Luis Obispo), using Chardonnay and Pinot noir, and the San Joaquin Valley (Fresno), using Chardonnay and Carignan. At each location, two blocks were selected per variety. Weather stations were installed in the vineyards before budbreak to monitor the real-time powdery mildew risk index. Fourteen treatments included three biofungicides (Bacillus subtilis, Streptomyces lydicus, and extract of Reynoutria sachalinensis) applied at different intervals (weekly, biweekly, and mildew risk index-based), biofungicides rotating with synthetics, synthetic standard only, and an untreated control. Treatments started at bloom. Disease incidence and severity were rated biweekly, approximately one week prior to veraison, and yield and berry chemistry were measured at harvest. Biofungicide by itself did not show a better efficacy than synthetic standard on disease incidence or severity. However, the rotation of bio-fungicide and synthetic showed similar efficacy against disease severity as synthetic standard alone on both varieties at each location. No significant difference in yield or berry chemistry was found between biofungicide and synthetic treatments. The ongoing project will be repeated in 2024.
Funding Support: CDFA-Specialty Crop Block Grant Program and California State University Agricultural Research Initiatives
Add your content.
lsdslfjsdlfjlksdjflskdjf
