Optimizing anaerobic soil disinfestation to manage emerging soilborne diseases in tomato protected culture systems in the North Central Region

View the project final report

Commodities

• Vegetables: tomatoes

Practices

• Crop Production: cover crops, high tunnels or hoop houses
• Education and Training: extension, on-farm/ranch research, participatory research
• Pest Management: biofumigation, biological control, cultural control, disease vectors
• Production Systems: Protected culture
• Soil Management: organic matter, soil microbiology

This proposal, entitled “Optimizing anaerobic soil disinfestation to manage emerging soilborne diseases in tomato protected culture systems in the North Central Region”, addresses an emerging issue in intensive vegetable farming systems. Higher demand for local produce as well as increasing weather extremes have led to expanded adoption of greenhouse and high tunnel vegetable production systems in the North Central United States.

Continuous production with little rotation in these systems has resulted in the emergence of soilborne disease complexes that greatly reduce yield, quality, and profitability, especially in tomato production. Key diseases in these complexes include Verticillium wilt (Verticillium dahliae), black dot root rot (Colletotrichum coccodes), corky root rot (Pyrenochaeta lycopersici), and root knot nematode (Meloidogyne spp.). Management of soilborne diseases historically relied on environmentally damaging, energy intensive methods, such as fumigation and steam sterilization. Anaerobic soil disinfestation (ASD) is a promising disease management tactic in which soil is amended with a carbon source, irrigated to saturation, and tarped for several weeks. ASD is driven by and has a tremendous impact on beneficial soil microbial communities and soil health, yet our understanding of these impacts is not complete. Nor has ASD been evaluated or optimized for the North Central Region. It is critical to counter the effects of soilborne diseases on the sustainability of protected culture systems. The objectives of this project are to 1) optimize ASD for protected tomato culture, 2) generate new knowledge about how ASD affects soilborne diseases, beneficial soil microbes, and soil health, and 3) increase awareness and adoption of ASD technology in the region. The outcomes of the project are 1) increased farmer awareness and understanding of soilborne diseases and their management, 2) farmer understanding of the uses, mechanisms and benefits of ASD for disease management, and 3) adoption of ASD and integrated soilborne disease management strategies by community farmer-leaders leading to region-wide adoption. We will achieve these objectives and outcomes through greenhouse and growth chamber trials to optimize ASD and by participatory on-farm trials using the mother and baby trial design, which will allow us to introduce, evaluate and disseminate ASD in one series of trials. The impacts of ASD on soil health and soil microbial communities will be examined in the mother portion of these trials. Project progress will be evaluated using Outcome Mapping, which fosters close collaboration between program participants.

Our project will lead to both learning and action outcomes to benefit vegetable farmers in the North Central Region. We will increase farmers’ awareness and understanding of soilborne diseases and potential methods for managing these diseases through workshops and factsheets. Farmers will learn the skills to apply ASD through workshops and participatory on-farm trials. Ultimately, achievement of these learning outcomes will lead to action outcomes, including farmer adoption of ASD and integrated soilborne disease management strategies. The findings of our project will benefit farmers, extension agents, and plant health professionals.