More than 50 years ago, a small potato plot just outside of Newfoundland was infected with Synchytrium endobioticum, a soil-borne fungus responsible for a devastating potato disease. Results from the research are promising.
Purposely infecting a crop with the fungus responsible for shutting down the movement of seed potatoes from P.E.I. to the U.S. in 2021 may seem counterintuitive, but for scientists at the Avondale Research Farm, located about 67 kilometres west of St. John’s, Newfoundland, it’s the perfect opportunity to study one of the potato industry’s greatest foes.
Potato wart is extremely persistent, and currently the only effective way to control the disease is to prevent the movement of soil from one location to another. While several potato wart initiatives are underway at Agriculture and Agri-Food Canada, Avondale is the only outdoor field site in Canada where potato wart research can be conducted in a farm environment — and it’s the place Dr. Linda Jewell calls her work home.
Her team’s research goal is clear: develop strategies to mitigate the devastating impact of potato wart on growers across Canada.
“Once potato wart is in the soil, it’s incredibly difficult to eliminate,” Jewell says. The worm-like pathogen resides dormant, resurfacing only when conditions are right, which complicates efforts to eradicate it. “It can survive for decades, making traditional control methods ineffective.”
At Avondale, researchers not only test various potato varieties for resistance but also explore potential control strategies, such as the use of fungicides and other chemical compounds.
“Much of our work involves identifying resistant potato varieties and assessing control methods,” Jewell says. “When it comes to fungicides, traditional products don’t effectively combat potato wart, so we need innovative approaches.”
Given the disease’s implications for trade and food security, this kind of research is paramount.
“The presence of potato wart can shut down trade routes, hindering the movement of potatoes across provinces,” Jewell says, noting that although potato wart is currently limited to Newfoundland and certain areas of Prince Edward Island, control measures must remain vigilant. “We have clear evidence that potato wart primarily moves through soil or infected potatoes, but any shifts in agricultural practices could put other regions at risk.”
The work at Avondale also incorporates examining the biology of the pathogen itself.
“Understanding what triggers spore germination is essential,” Jewell says. “There are hundreds or thousands of spores present in the soil, but not all will germinate when a susceptible potato is planted. Figuring out what activates those spores can help inform our control strategies.”
Results from the research to date are promising.
“With renewed interest and advances in genetic and genomic tools, we’re better equipped than ever to tackle this challenge head-on,” she says. “There’s tremendous potential for this research to lead to meaningful solutions that will have a positive impact on growers across the country. We’re committed to finding effective strategies that could change the landscape of potato farming for the better.”
National Potato Wart Response Plan Set to Roll Out in 2025
The newly finalized National Potato Wart Response Plan will take effect with the 2025 potato crop, introducing crucial measures aimed at containing and controlling the spread of potato wart.
This plan replaces the previous Potato Wart Domestic Long-term Management Plan (2009) and establishes enhanced protocols for managing this significant agricultural pest.
Key New Requirements for Restricted Fields:
- Farm-Based Preventive Control Plan (PCP): Growers must develop a formal written plan detailing how their operation identifies and mitigates risks associated with the introduction and spread of potato wart.
- Equipment Cleanliness: All loose soil must be removed from machinery and equipment before exiting a restricted field, in accordance with the preventive control plan.
- Seed Potato Certification: Certification for seed potatoes grown in restricted fields will no longer be available, and production in index and adjacent fields will continue to face ongoing restrictions.
- Soil Sampling and Analysis: Additional soil sampling and analysis will be required before any restrictions can be lifted from restricted fields.
- In-Province Movement Regulations: There will be increased requirements governing the movement of potatoes and root crops produced in potato wart restricted fields within the province.
For complete details on the National Potato Wart Response Plan and guidelines, read the full plan here.
