BioWorks - BotryStop WP - 30 lbs

BotryStop WP Biological Control for Botrytis Gray Mold

This BioWorks wettable powder is built on a living fungus, Ulocladium oudemansii strain U3, at 45% of the product. Each gram carries at least 80 million colony forming units of live spores. Sprayed onto the crop, those spores settle on dead and senescing tissue such as spent petals and old leaves. They germinate there and colonize that tissue, which is exactly where Botrytis cinerea likes to get started. The U3 strain claims the space and the nutrients first, so the pathogen finds no room to establish. BioWorks describes it as a true antagonist that leaves live plant tissue untouched. Because it works by competition, the label calls resistance highly unlikely. Targets include gray mold, Botrytis blight, Sclerotinia white mold and Monilinia blossom blight. The label covers greenhouse and nursery ornamentals, bedding plants, vegetables, berries, tree fruit and hemp. Re-entry is 4 hours, and sprays can continue up until harvest. The signal word is Warning, because the powder can cause temporary eye injury. This 30 lb bag suits larger greenhouse ranges and field blocks sprayed on a steady schedule.

Running a Preventative Botrytis Fungicide Program

A botrytis fungicide that works by occupation has to reach the tissue before the pathogen does. Start spraying when cool, humid weather favors gray mold, or as flowering begins. Repeat every 7 to 10 days through the risk period. Label rates run 2 to 4 lb per acre, and most row crops take up to 100 gallons of spray. For hand sprayers, the BioWorks small-volume chart works out to about one to two tablespoons per gallon. Pre-slurry the powder in a separate bucket before it goes into a partly filled tank. A non-ionic surfactant helps it wet and spread across the leaf. Keep the agitator running and spray the mix the same day, since it should never sit overnight. Wet the canopy thoroughly but stop short of runoff. It cannot go through any irrigation system. Tank-mix it with no more than one other product, and jar-test that pairing first. Store the bag cool and dry at or below 68°F. Refrigerated, it keeps about 18 months, or a year at room temperature.

Key Features

• Ulocladium oudemansii U3: 45% active, at least 8 x 10⁷ CFU per gram.
• Competitive Exclusion: Occupies dead tissue before Botrytis can colonize it.
• Broad Target List: Gray mold, Sclerotinia white mold and Monilinia blossom blight.
• Safe on Live Tissue: Non-invasive, with no damage to healthy plant tissue.
• Low Resistance Risk: A competition-based mode of action for rotation programs.
• 4-Hour REI: Short re-entry for greenhouse and field crews.
• Spray Up Until Harvest: Label allows applications right through harvest.
• 30 lb Bag: Sized for large greenhouse ranges and field acreage.

Technical Specifications