Exploring grower strategies and needs for enhancing organic disease management of tomato late blight

Abstract Late blight, caused by the oomycete Phytophthora infestans, poses a significant challenge to organic tomato and potato production systems across the globe. To enhance education and outreach programming pertaining to tomato organic late blight management in Wisconsin, we sought to identify grower strategies and needs through an online survey conducted during spring 2018. Our findings demonstrated that organic growers emphasized crop diversity, crop rotation and soil health in their late blight management decisions. Grower concerns about biopesticides were identified and suggest that the use of input-based products within integrated management programs could be enhanced by further research on effectiveness and modes of actions. Additionally, stronger emphasis on oomycete pathogen biology and the significance of late blight as a community disease were identified as important areas of emphasis in the development of organic disease management education programming and resources that promote more effective cultural and chemical disease management strategies that adhere to the regulation and principles underlying the USDA National Organic Program. The integration of a live polling questionnaire conducted in winter 2019 allowed us to corroborate findings from the online survey and underscored the importance of two-way learning to enhance outreach efforts between Extension and organic growers in Wisconsin and the surrounding upper Midwestern states.