Naresh Thevathasan: Mobilizing science and improving lives through mentorship

Posted on Wednesday, January 18th, 2023

Written by Dilshan Fernando

In the 1990s, while other agricultural scientists in Ontario were mostly planting crops in their research plots, agroforestry pioneers Andy Gordon and Naresh Thevathasan were instead planting trees—and turning heads.

Naresh and Andy at the Ontario Agricultural College were working to give producers a long-term income prospect and environmentally friendly alternative to monocultures, by intercropping lucrative hardwoods among rows of cash crops.

Naresh Thevathasan

This was mostly unheard of in Ontario at the time. But years later, this approach would be considered a promising form of carbon sequestration. Naresh and his colleagues were far ahead of the curve.

Locally made groundnut seed separation apparatus in Tamil Nadu, India, 2012. Photo credit: Vidiyal Seed Growers' Association, Madurai District, South India.

Naresh's career has been distinguished by environmental awareness, producer assistance and student mentoring.

Naresh grew up in Batticaloa, eastern Sri Lanka, and graduated with an agronomy major from Eastern University. He developed an interest in tree-based intercropping systems after the government there started wading into diversification in agricultural systems. His father, K. Thevathasan, his early mentor and Assistant Director of Agriculture in the Department of Agriculture at the time, was jubilant about his son's recruitment to Eastern University as a junior faculty member.

"He was very proud that his son was following his footsteps," says Naresh. "He wanted me to join the Department of Agriculture, so that there's a legacy." However, Naresh had his eye on a career in academia. That accelerated when he wrote an impressive funding proposal about growing up-country vegetables such as carrots and leeks in low-country, high-humid environments, to give more income to smallholders in Sri Lanka. The proposal earned him a Commonwealth scholarship to pursue graduate studies at the University of Guelph.

Through the years, he nurtured his agroforestry research with numerous international collaborations in India, Ghana, Rwanda, the Democratic Republic of Congo, Sri Lanka and many more. His project in India, for example, looked at how improved seeds can be produced via Open Distance Learning to enhance rural agricultural crop yields supporting India's development goals of growth, equity, and sustainability.

Best Management Practice field demonstration site for groundnut seed production, Tamil Nadu, India, 2012. Photo credit: Vidiyal Seed Growers’ Association, Madurai District, South India.

The joy of conducting research is when farmers offer you samples from their harvest, says Naresh.

"Recently a landowner from close to Ottawa brought me two bottles of maple syrup and he said to me, 'Naresh, for all the time you spent, this is the least I can do.' He remembered me, and this is a great thing. The most important thing for me is training young minds," he says, reminding us how much satisfaction his farmer-mentees bring from successfully adopting his scientific findings.

Field Demonstration site to produce virus free cassava cuttings, Tamil Nadu, India, 2012. Photo credit: N. Thevathasan, Madurai District, South India.

Mentoring graduate students to become thought leaders in their fields is a highlight of Naresh's career. For this, he also received an Honorary Doctor of Science degree in 2011 from Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana.

One Ghanian student, Samuel Tetteh-partey, who came to U of G to study under Naresh, has now become an illustrious international scholar working with the United Nations. He publishes as many as four peer-reviewed papers every year. "So, when I see transformations like this, resulting from my guidance, it gives me a lot of pride," he says.

Even as a retired professor, Naresh has his work cut out for more research.

He says, that in one of his current projects, he and his team are trying to increase terrestrial acreage of trees in riparian buffers—a forest area adjacent to a stream, lake or wetland. Southern Ontario's biggest watershed, the Grand River, is where they spend time the most.

Fostering networks and partnerships with farmers including smallholders, policy makers, and graduate students who are mostly from the Global South is a clear highlight of Naresh's arduous career, and something that attracts him to CIRCLE.

This is why he says to Canadian students who want to conduct research in India, South Asia, or any Global South country, "give respect to that country and remember that there's a wealth of knowledge out there. So, learning that knowledge is an advantage for your career . . . and, if you end up in Global Affairs Canada or as a Member of Parliament or as Prime Minister, you will remember the countries that you visited, and extend your helping hand to uplift the communities you had worked with."

On-site farmer training class on seed production technologies, Tamil Nadu, India, 2012. Photo Credit: K. Thevathasan.

Dilshan Fernando is a student writer for CIRCLE. He is in the third year of his PhD at the University of Guelph.

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