Tobie Blanchard

Growing up in a suburb of Calgary, Alberta, Canada, Tristan Watson didn’t aspire to a career in agriculture. Watson was interested in microbiology and was considering medical school when he did an honors thesis with an agricultural bacteriologist.

“That was my first exposure to agriculture,” Watson said. “We were trying to develop biocontrol agents using bacteria to control various fungal pathogens on apple trees.”

It was at that point that Watson said he fell in love with agricultural research and set out on a path that would bring him to the LSU AgCenter as an assistant professor of nematology in the Department of Plant Pathology and Crop Physiology.

Watson’s research focuses on nematodes, microscopic roundworms he describes as sort of in between a plant pathogen and an insect. Nematodes can be detrimental to crops. He has statewide responsibility for nematode management on all crops grown in Louisiana. He also serves as the director of the LSU AgCenter’s Nematode Advisory Service, which provides diagnostic services to growers, extension agents and research personnel.

“Every single crop we grow here has a couple of nematode species. But they are particularly damaging on sweet potato because they feed on the root system, and that is what we are trying to market in sweet potato production,” he said.

Watson is part of a multistate team of researchers that recently received a U.S. Department of Agriculture National Institute of Food and Agriculture grant of more than $5 million to develop an integrated management strategy for the invasive guava root-knot nematode.

“What we are focusing on is the development and characterization of sweet potato varieties with resistance,” he said. “Our partners in North Carolina State University will be doing field trials on cultural management strategies.”

Sweet potato fields in North Carolina have widespread infestations of this nematode while Louisiana doesn’t yet. Watson said the team is trying to control this pest from a national level so they can have a preemptive strategy and all be on the same page as they move forward with control options.

“It’s too complex for one person to do this all and be able to hit all the different parts that need to be explored to get meaningful answers,” he said. “You need a multidisciplinary team, and that is what we have.”

Watson first studied nematodes while pursuing his Ph.D. at the University of British Columbia. He conducted research on nematodes on cherries at the Agriculture and Agri-Food Canada Summerland Research and Development Center in the Okanagan Valley.

After finishing his Ph.D., Watson went to the University of Florida, where he worked at the Gulf Coast Research and Education Center.

“That is where I really dove deep into the nematode work. They have a great program, and I was able to work on different crops — strawberries, tomatoes, vegetables and some specialized crops like hops, hemp and artichokes.”

Watson joined the faculty of the LSU AgCenter in March 2020, right as the pandemic sent workplaces into lockdown. He said things were slow to start, but with his small team, they were able to get projects up and running and found a way to stay safe and work around the shutdown.

In addition to his research and extension responsibilities, Watson also teaches a graduate-level course on phytonematology. He also lectures in an undergraduate course where he gets to introduce students to nematodes.

“I guess I come from a nonconventional background in that there are no courses on nematology in Canada, I’ve never taken a plant pathology or nematology class so what I had to learn was through books and mentoring,” he said.

The diversity of his work in nematology keeps his job interesting, Watson said.

“Every day is a little different,” he said. “You get different problems that pop up. It’s like detective work and solving puzzles.”

Tobie Blanchard is the director of LSU AgCenter Communications.

(This article appears in the winter 2022 issue of Louisiana Agriculture.)

Tristan Watson, assistant professor of nematology, in the Sacred Valley, Peru, attending the Organization of Nematologists of Tropical America meeting in 2019. Photo provided by Tristan Watson

Tristan Watson, left, director of the LSU AgCenter Nematode Advisory Service, and Josielle Rezende, AgCenter research associate, examine soybean plants in a greenhouse at the AgCenter Central Research Station in Baton Rouge. Photo by Olivia McClure