Febina Mathew, professor and soybean pathologist, North Dakota State University
Febina Mathew is a professor and soybean pathologist in the Department of Plant Pathology, Microbiology and Biotechnology at North Dakota State University (NDSU). Originally from India, she holds an M.S. and PhD in Plant Pathology from NDSU. She lives in Fargo, North Dakota.
Where did you work before NDSU?
I was an assistant professor and field crops pathologist, and later an associate professor, at South Dakota State University.
Tell us a bit about what you’re working on at NDSU.
My research program focuses on understanding the biology of pathogens affecting soybeans and their interactions with host plants, with the goal of developing effective disease management strategies, particularly through fungicides (foliar and seed treatments) and host resistance. My soybean research focuses primarily on Diaporthe diseases, Fusarium diseases (root rot and sudden death syndrome), as well as viruses, Clonostachys and other emerging pathogens affecting soybeans in North Dakota. We also investigate Phomopsis stem canker of sunflower and the potential for pathogen movement between soybean and sunflower.
My research on Diaporthe/Phomopsis species spans 15 years and includes work on both soybean and sunflower, in collaboration with researchers in the U.S. and internationally, including Argentina, Australia, Brazil, Canada, Croatia, Germany, Italy, Serbia and Slovenia.
In sunflower, Phomopsis stem canker, caused by Diaporthe helianthi and D. gulyae, is an important disease in the U.S. northern Great Plains. In Manitoba, D. gulyae is also known to cause disease. Phomopsis stem canker can cause substantial yield losses, reported to reach up to 40 per cent, and is favoured by prolonged periods of high humidity, wet conditions and temperatures of approximately 20–25°C, particularly from the R1 to R5 growth stages. Disease symptoms become most apparent after flowering when characteristic brown stem lesions develop. As the disease progresses, the stem becomes hollow and weakened, increasing the risk of lodging under the weight of the head. Overall, sunflower yield declines by about 11.6 kg/ha (10.4 lb/acre) for every percentage-point increase in disease severity.
The project, “Determining fungicide effectiveness to manage Phomopsis stem canker,” partially funded by Manitoba Crop Alliance, analyzed 80 fungicide trials conducted from 2009 to 2025. These trials were conducted across 80 location-years in Minnesota, Nebraska, North Dakota and South Dakota and evaluated fungicides from several chemical groups for management of Phomopsis stem canker.
A single fungicide application at the R1 growth stage, when the miniature floral head is formed on the sunflower plant, provided the most consistent yield benefit compared with untreated plots. Among the products tested, those containing pyraclostrobin reduced disease severity by more than 30 per cent and increased yield by at least five per cent.
The economic benefit of fungicide application was greatest when disease pressure was high. In individual trials, a single pyraclostrobin application increased yield by 543 to 842 lb/acre under high disease pressure, compared with 155 to 343 lb/acre under low or no disease pressure.
Economic analysis showed that a pyraclostrobin application costing approximately $13.27/acre would require about 112 lb/acre of additional yield for oilseed sunflower or 88 lb/acre for confection sunflower to break even at the 2025 prices used in the study.
What does this mean for farmers in Manitoba?
For Manitoba sunflower farmers, the study provides useful guidance, although the fungicide trials were conducted primarily in the U.S. northern Great Plains. The main message is that fungicides are most likely to provide an economic benefit when disease pressure is high and yield is being limited by the disease, rather than simply applying a fungicide in every field.
Farmers should also consider an integrated approach to manage Phomopsis stem canker, which involves the use of disease-tolerant hybrids where available and crop rotation. Sunflower is rotated every three to four years, and crops such as wheat and corn can help reduce pathogen levels in the field. Once the pathogen is established we cannot eliminate it, but we can reduce the amount of pathogen present.
When deciding whether to spray, I would ask: How much disease pressure are we likely to have? Did I see the disease the last time I grew sunflowers? Did my neighbour have it? What did I see in the same variety previously? Then consider the fungicide cost, sunflower price and expected yield to determine whether an application is likely to provide a return on investment.
Who inspired you to get into this area of work?
My former PhD advisor, Dr. Samuel Markell at NDSU, encouraged me to investigate a disease that had re-emerged after being first discovered more than a decade earlier and had initially been considered a minor disease. Not fully understanding why it was re-emerging sparked my curiosity and motivated me to study the disease under his guidance.
What can you say about the value of farmers providing funding and support to your organization?
It’s invaluable; it helps ensure our research addresses the issues that matter most to farmers. My grandfather was a farmer, so if I put myself in his shoes, I know he would be asking, “How much can I invest in protecting my farm and getting the maximum benefit out of it?” That’s what we are trying to answer through our research. We combine pathogen biology with field-based research to find practical solutions for farmers.
How does that farmer funding and support directly benefit farmers?
We are aiming to turn research into practical, affordable solutions that can be used in the field. In this case, funding allows us to evaluate fungicide programs, yield impacts and economic returns under field conditions. That information helps farmers make better-informed decisions about when to spray, which products or modes of action to use and when a fungicide application is likely to provide a positive return.
How do you spend your time outside of work?
I have training in a traditional dance style of India, specifically Bharatanatyam. Following my training, I have been practicing multiple dance styles from India and other countries since the age of four. I continue to practice dance in my free time and occasionally participate in local cultural and charity events. I also enjoy traveling and connecting with people from diverse backgrounds and cultures.
What is the best piece of advice you’ve received?
One of the best pieces of advice I have received came from our department head, Dr. John McEvoy: “Trust your gut. If something does not feel right, even when you cannot quite explain why, it is worth listening to that instinct.” I have not been good at trusting my instincts, but his advice has stayed with me. It has encouraged me to pay closer attention to that inner voice.
What is your favourite food?
My favourite food is tiramisu! I love the combination of the three Cs: coffee, cream and cocoa.
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