GRAPES HAVE A NEW PROTECTOR - MEVALONE® NOW APPROVED FOR POWDERY MILDEW IN CALIFORNIA

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May 15, 2025, 10:00 ET

High Performance, Novel Mode of Action, Controls Bunch Rot and Powdery Mildew in Grapes

DURHAM, N.C., May 15, 2025 /PRNewswire/ -- In January 2024, Sipcam Agro USA proudly launched Mevalone^®, an innovative biofungicide for the control of Botrytis cinerea (bunch rot) on grapes in California, and is pleased that this latest regulatory approval extends the application of Mevalone on wine, table and raisin grapes for use on powdery mildew in California. Mevalone has been a revolutionary fungicide for grape growers in the U.S. and Europe for several years and with the additional powdery mildew regulatory approval, arrives in time for the start of the 2025 growing season.

While Botrytis is the most destructive plant pathogen in grapes, powdery mildew is also a persistent U.S. vineyard threat. Mevalone is a formidable tool to assist growers in their fight against both diseases. Powdery mildew, caused by the fungus Erysiphe necator, affects grapevines, especially in California's wine regions. It thrives in warm, dry climates and coats leaves, shoots, and grapes in a white, powdery fungal growth. The disease reduces yield, fruit quality, and wine value. Control is challenging due to fungicide resistance and the need for frequent applications. Integrated disease management, including canopy management, resistant cultivars, and fungicide rotation—is essential to reduce economic losses and ensure sustainable grape production.

Mevalone is an eco-friendly, resistance-management-tool option that fits well in integrated programs and organic production. Synthetic fungicides remain essential for high-pressure situations but require careful resistance management and monitoring for residues.

Mevalone's naturally derived Active Ingredients (AI) Thymol (garden thyme), Geraniol (Damask rose) and Eugenol (clove oil), are part of a large class of plant secondary metabolites called terpenes (isoprene polymers) that exhibit a safe toxicological and environmental profile with no risk of interference with fermentation and no effect on the aroma or taste of wine. These highly effective actives were found to be exempt from the requirements of a tolerance—the maximum amount of a pesticide allowed to remain in or on a food commodity—and permitting Mevalone a maximum residue limit (MRL) exemption in the US, allowing vineyards to export product outside the USA as compared to other fungicides with MRL limitations. For growers looking at resistance management options, Mevalone has one of the lowest risks of developing Botrytis/Powdery Mildew resistance as a FRAC Group BM01 Biological, with no known cases, globally, after years of use.

Mevalone is formulated with Eden Research's patented Sustaine^®Technology and is registered and available in 17 US states including AL, AZ, CA, FL, GA, ID, IL, MI, MO, MS, NC, NY, OR, PA, TX, WA and WV.

Comparison of Mevalone and Synthetic Fungicides for Soft Rot (botrytis)/Powdery Mildew Control in Grapes

Feature	Mevalone	Synthetic Fungicides
Mode of Action	Natural terpenes disrupt fungal development	Target-specific inhibition (e.g., sterol biosynthesis)
Resistance Risk	Low-No resistance known (multi-site action)	High (single-site modes of action prone to resistance)
Residue	Residue-free	Often leave chemical residues
Pre-Harvest Interval (PHI)	3 days	Varies; some have long PHIs
Environmental Impact	Low (biodegradable, non-toxic)	Higher (chemical runoff, non-target effects)
Effectiveness	Strong, especially in IPM or early-season use	High; typically, more potent against severe outbreaks
Cost	Moderate to high	Low to High: some are lower-cost options but do not control soft rot

"Speaking to grape growers across California, Botrytis and powdery mildew are without question two of the most critical diseases affecting production in California," said Brent Marek, CEO of Sipcam Agro USA. "With this approval, growers now have a more effective tool to manage powdery mildew with a novel mode of action that is well recognized by experts in agronomy and fungicide resistance in other countries."

To help educate licensees about Botrytis solutions, Sipcam Agro USA has generously partnered with AgCEUOnline to sponsor the newest Continuing Education course: Effective Management of Botrytis in Grape Vineyards. Log in today to earn CE credit!

For more information, visit the Mevalone site and learn more about Mevalone in this video.

About Sipcam:
Headquartered in Durham, North Carolina, Sipcam Agro USA Inc., is owned by the Sipcam-Oxon Group, a privately owned Italian company recognized worldwide for its chemical formulation and manufacturing expertise. For more information, visit www.sipcamagrousa.com. ©2025 Sipcam Agro USA, Inc. Sipcam logo is a trademark of Sipcam Agro USA, Inc. Mevalone^® is a trademark of EDEN Research's PLC patented Sustaine^® Technology distributed by Sipcam Agro USA, Inc. Always read and follow label directions.

SOURCE Sipcam Agro USA