It is labeled for use on grapes, leafy and fruiting vegetables, strawberries and potatoes, according to a news release.
It is active on a host of fungal diseases, including Botrytis and Sclerotinia as well as bacterial diseases, such as Xanthomonas and Erwinia.
The product contains the patented QST 713 strain of Bacillus subtilis.
It works by stopping spore germination, disrupting cell membrane and inhibiting attachment of the pathogen to leaves.
Serenade Optimum is best used to suppress diseases early in the season before pressures peak, according to the Bayer website.