P-055 - Exploring the efficacy of LifeGard™ (Bacillus mycoides "BmJ") for Sustainable Management of Downy Mildew (Plasmopara viticola) in Grapes

Downy mildew (Plasmopara viticola) poses a significant threat to grape production in the Northeastern United States, where humid conditions favor disease development. While fungicides remain the primary management strategy, concerns over resistance and environmental impact necessitate alternative approaches. This study examines the integration of Bacillus mycoides isolate J (BmJ), a biological control agent marketed as LifeGard, into a conventional fungicide program for managing downy mildew in Vitis vinifera ‘Chardonnay.’ Field trials demonstrated that LifeGard, when used with fungicides (11% severity) or other biocontrols (26% severity), significantly reduced disease severity compared to untreated controls (87%), offering protection comparable to conventional fungicide programs (12%). These findings suggest that BmJ reduces both disease incidence and severity, potentially through the induction of resistance-related metabolites. To further elucidate the mechanism of induced resistance, this study characterizes temporal metabolite changes in grapevine leaves following BmJ application. Understanding these biochemical responses will inform sustainable disease management strategies, enhancing viticulture resilience while reducing fungicide reliance.