U of S researcher working on an innovative way to control fusarium head blight

By: Delaney Sieferling

Since the devastating outbreak of fusarium head blight (FHB) in Saskatchewan crops in 2012, the agricultural research community has been trying to come up with options to control this devastating disease. 

But with only moderately resistant varieties available today, and fungicides working as a short-term and partial fix, so far there are no outstanding solutions.

One University of Saskatchewan (U of S) researcher, however, is taking an innovative approach to changing that.

Dr. Vladimir Vujanovic, an Associate Professor who specializes in microbiology, launched a research project last March looking at the potential to use biological control agents (BCAs) to help control FHB in Saskatchewan.

A research technician applies the BCA and chemical pesticide spray to test plots as part of Dr. Vujanovic’s research.

Specifically, he is testing the efficacy of the microparasite Sphaerodes mycoparasitica in controlling FHB in commonly grown varieties of wheat and durum in the province.

BCAs are different than other disease control options in some very significant ways, he says.

First, this specific microparasite, S. mycoparasitica, is native to Saskatchewan; it was discovered by Dr. Vujanovic and his team in 2009 and isolated from its fusarium hosts on kernels associated with FHB symptoms. They have since described it as a new fungal species.

Second, BCAs are considered a more environmentally sustainable and friendly disease control method, because they are natural, native and do not rely on agrochemicals.

Finally, this specific biocontrol agent would offer a more targeted and therefore effective approach to fighting FHB than other more general solutions, Dr. Vujanovic says.

“It’s similar to how we try to avoid using general-spectrum antibiotics in the medical field because of their potential secondary effects,” he says.

“Here I am looking to develop a pathogen-specific microparasite or pathogen control agent so that we can specifically target the FHB pathogens, thus protecting the other beneficial microorganisms or plant microbiome.”

The S. mycoparasitica microparasite has the ability to directly attack more than one of the pathogenic species that cause FHB and their respective mycotoxins, Dr. Vujanovic says.

Because of this, it can help prevent yield loss as well as the accumulation of mycotoxins in the plant – the same mycotoxins that are heavily regulated by Canada’s food safety standards and can cause the crop to be downgraded significantly, sometimes below food grade, leaving farmers with no marketing options.

So far, Dr. Vujanovic is just into the three-year project but he has already gained valuable data from year one. Results from 2018 showed higher yields and lower FHB levels on test plots that had received an application of the BCA alone, or a combination of the BCA and other commercial products, during the seeding and flowering stages.

Testing the BCA in combination with other products is important, Dr. Vujanovic says, as the overall goal will be to use it as a vital chain loop within an integrated crop management approach.

“What is important is that we create the best combination of the BCA products with elite cultivars, chemical pesticides and standard agricultural practices” he says.

To this end, he has been working closely with breeders at the U of S Crop Development Centre and Agriculture and Agri-Food Canada, as well as researchers at the Saskatchewan Research Council, to scale up the product and optimize its formulation.

The end goal is that, once the research is complete, the agriculture industry in Saskatchewan will be a lot closer to having one more commercial product available to help control FHB throughout the prairies, he says.

“We are interested in helping farmers maximize their returns because that is good for the economy. We are also interested in protecting the sustainability of the agriculture industry through eco-friendly disease control options.”

Dr. Vujanovic’s research is funded by the Saskatchewan Wheat Development Commission, the Natural Sciences and Engineering Research Council of Canada and the Government of Saskatchewan’s Agriculture Development Fund.