Presidential Green Chemistry Challenge: 2003 Small Business Award
AgraQuest, Inc. (now Bayer CropScience)
Serenade®: An Effective, Environmentally Friendly Biofungicide
Innovation and Benefits: Serenade® is a new biofungicide for fruits and vegetables based on a naturally occurring strain of bacteria. Serenade® is nontoxic to beneficial and other nontarget organisms, does not generate any hazardous chemical residues, and is safe for workers and groundwater. It is well-suited for use in integrated pest management (IPM) programs and is listed with the Organic Materials Review Institute (OMRI) for use in organic agriculture.
Summary of Technology: Serenade® biofungicide is based on a naturally occurring strain of Bacillus subtilis QST-713, discovered in a California orchard by AgraQuest scientists. Serenade® has been registered for sale as a microbial pesticide in the United States since July 2000. It is also registered for use in Chile, Mexico, Costa Rica, and New Zealand. Registration is pending in the Philippines, Europe, Japan, and several other countries. The product is formulated as a wettable powder, wettable granule, and liquid aqueous suspension. Serenade® has been tested on 30 crops in 20 countries and is registered for use in the United States on blueberries, cherries, cucurbits, grape vines, greenhouse vegetables, green beans, hops, leafy vegetables, mint, peanuts, peppers, pome fruit, potatoes, tomatoes, and walnuts. It is also registered for home and garden use. AgraQuest has been issued four U.S. patents; several international patents are pending on the QST-713 strain, associated antifungal lipopeptides, formulations, and combinations with other pesticides.
Serenade® works through a complex mode of action that is manifested both by the physiology of the bacteria and through the action of secondary metabolites produced by the bacteria. Serenade® prevents plant diseases first by covering the leaf surface and physically preventing attachment and penetration of the pathogens. In addition, Serenade® produces three groups of lipopeptides (iturins, agrastatins/plipastatins, and surfactins) that act in concert to destroy germ tubes and mycelium. The iturins and plipastatins have been reported to have antifungal properties. Strain QST-713 is the first strain reported to produce iturins, plipastatins, and surfactins, as well as two new compounds with a novel cyclic peptide moiety, the agrastatins. The surfactins have no activity on their own, but low levels (25 ppm or less) in combination with the iturins or the agrastatin/plipastatin group cause significant inhibition of spores and germ tubes. In addition, the agrastatins and iturins have synergistic activities towards inhibition of plant pathogen spores.
The Serenade® formulation is available as a wettable powder, wettable granule, and aqueous suspension that is applied just like any other foliar fungicide. It can be applied alone or tank mixed; it can also be alternated with traditional chemical pesticides. Serenade® is not toxic to beneficial and nontarget organisms, such as trout, quail, lady beetles, lacewings, parasitic wasps, earthworms, and honey bees. Serenade® is exempt from tolerance because there are no synthetic chemical residues and it is safe to workers and ground water.
Serenade®'s wettable granule formulation is listed with the Organic Materials Review Institute (OMRI) for use in organic agriculture and will continue to be listed under the National Organic Standards, which were enacted in the United States in October 2002.
Serenade®'s novel, complex mode of action, environmental friendliness, and broad spectrum control make it well-suited for use in integrated pest management (IPM) programs that utilize many tools, such as cultural practices, classical biological control, and other fungicides. Serenade® can be applied right up until harvest, providing needed pre- and post-harvest protection when there is weather conducive to disease development around harvest time.