Cross section of a tomato plant stem reveals darkened vascular tissue from R3bv2. Credit: Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, Bugwood.org, CC BY-NC 3.0 US, cropped for use.
Background
Ralstonia solanacearum race 3 biovar 2 (R3bv2) is a highly destructive bacterial pathogen that poses a unique threat to Minnesota’s potato industry and could devastate agriculture nationally if not controlled. What makes this disease especially dangerous is not just its capacity to cause wilt and death in potatoes, but also its ability to survive in wild nightshade plants that often grow near potato fields. These plants, which show no symptoms, can still harbor and spread the pathogen. This hidden aspect of the disease makes traditional approaches to disease management less effective and increases the risk of sudden, hard-to-predict outbreaks.
Taken together, these approaches are expected to lead to significant improvements in invasive species management. The project will produce science-based recommendations on which potato varieties are least susceptible, how to manage nightshade weeds more effectively, and what sanitation and monitoring protocols are most likely to prevent outbreaks. Outcomes from this work will not only help Minnesota’s growers protect their livelihoods but will also inform national biosecurity policies, offering a roadmap for keeping this high-risk pathogen out of agriculture for the long term.
Research questions
- How does Minnesota’s climate affect the pathogen’s ability to survive in both commercial potatoes and wild nightshades?
- When and where is the pathogen most likely to persist or die off?
- What are the differences between different strains of the pathogen? Is one more dangerous than another?
- What are the best practical, field-ready tools to detect infections early?
- Which potato varieties are least susceptible?
Practical implications
Findings from this work will provide critical, locally relevant information for growers and regulators to stop infections before it’s too late. Regulators will be able to tailor quarantine measures and surveillance strategies more precisely, avoiding unnecessary restrictions while still protecting crops. The project will produce science-based recommendations on which potato varieties are least susceptible, how to manage nightshade weeds more effectively, and what sanitation and monitoring protocols are most likely to prevent outbreaks. Outcomes will not only help Minnesota’s growers protect their livelihoods but will also inform national biosecurity policies, offering a roadmap for keeping this high-risk pathogen out of agriculture for the long term.
Findings
This project began in January 2026 and is in progress for the next several years. Please check back at a later time for updates.
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