SOD: SOLUTIONS FOR ORGANIC FARM DISEASES: SUPPRESSING SOILBORNE PATHOGENS IN VEGETABLE HIGH TUNNELS

Crop diseases are a significant problem for organic vegetable farmers in the US with up to 75% yield loss due to soilborne plant pathogens. Steaming the soil and Anaerobic Soil Disinfestation (ASD) are two promising management approaches that can help organic growers suppress pathogens without using synthetic fungicides or fertilizers. However, there is little science-based research on the efficacy of soil steaming and ASD methods or data on the recovery of the microbiome and nutrients post-steaming and ASD treatments. In order for these pathogen management approaches to be effective, it is paramount to understand the underlying biological mechanisms behind these approaches and to capture the willingness of farmers to adopt such technologies. Our goal is toconduct management trials and in-person/online surveys to help organic and transitioning to organic farmers reduce high tunnel soilborne diseases.Objective 1. What Works? To compare the efficacy of ASD and soil steaming for suppressing soilborne diseases of vegetables with a focus on high tunnel tomatoes (Research).Objective 2. Who Survives? To determine soil microbial community recovery (composition/diversity) after steaming and/or ASD and impacts on plant and soil health.Objective 3. Why Adopt These Methods? Is it Worth it? To understand the factors that affect farmers' willingness to adopt sustainable soilborne disease management practices and educate growers on the management practices.Plans/Milestones: We will conduct controlled high tunnel experiments at an USDA-ARS research station in Ohio, efficacy trials on organic farms in Pennsylvania and Ohio over the duration of the grant, and address farmers' needs for adoption with interviews, surveys and conduct a cost benefit analysis.Relevance to Program Goals: Two research priorities of the National Organic Standards board are addressed in this proposal: "Development of systems-based plant disease management strategies are needed to address existing and emerging plant disease threats," and "More research is needed to fully understand the relationship between on-farm biodiversity and pathogen presence and abundance."