Oral: Bacterial Disease Management
Investigation of the anti-bacterial activity of SERENADE® ASO against bacterial diseases of crops
T. SMITH (1), T. Knobloch (2) (1) Bayer, Crop Science Division - Biologics Research, U.S.A.; (2) Bayer, Crop Science Division - Small Molecule Research, France
Bacterial diseases of agricultural crops are costly with losses estimated at $10 billion per year. Current management strategies often use a multifaceted approach, including biological control. The biological-based product, SERENADE® ASO, is a known tool in integrated foliar spray programs to combat fungal diseases in fruits and vegetables, based on fungal cell membrane disrupting properties of lipopeptide chemistry produced by Bacillus subtilis QST-713. In addition, SERENADE® ASO has proved helpful to growers in managing bacterial diseases, such as Pseudomonas syringae pv. tomato and Xanthomonas campestris pv. vesicatoria, causal agent of bacterial speck and spot, on crops such as tomato and pepper. Recent research using both in vitro and in vivo tools point to two main actions contributing to the antibacterial activity of SERENADE® ASO: a direct antibacterial effect from biological chemistry produced by QST-713 during fermentation and an indirect effect on the plant. Different approaches were applied to eliminate potential activity from living cells in SERENADE® ASO to examine the role of biological chemistry. Research with Arabidopsis treated with SERENADE® ASO showed up-regulation of several pathways associated with host defense, and microscopy studies using tomato seedlings revealed transient changes in the condition of stomata openings. Additional research is ongoing to better characterize the mechanism of SERENADE® ASO against plant pathogenic bacteria.