New Research Tracks Flea Beetle Resistance & the Beneficial Insects Helping Protect Canola

Thursday, June 18, 2026

By Jeanine Moyer

Flea beetles are no strangers to Prairie canola growers. These persistent pests pose a threat year after year, causing more than tens of millions in economic losses annually across Alberta, Manitoba and Saskatchewan.

Growers have a limited number of tools to manage flea beetles. But a recent Prairie-wide study shows that while seed treatments and foliar insecticides remain the go-to options, beneficial insects are also playing an important, and often overlooked, role in keeping flea beetle populations in check.

The five-year Prairie-wide research project, which ran from 2021 to 2026, was led by Boyd Mori, assistant professor of agricultural entomology at the University of Alberta. The work took a closer look at how well current pest management tools are holding up, and what other biological supports may already be at work in canola fields.

Monitoring flea beetle sensitivity

The first key objective of the project was to survey striped and crucifer flea beetle populations to measure their susceptibility to neonicotinoids. By sampling across all three Prairie provinces, Mori and his research team, with the objective led by postdoctoral fellow Aziz Ullah, set out to identify any changes in sensitivity that could signal developing resistance.

“The goal was simple: ensure growers continue to have reliable protection when they plant canola,” explains Mori.

Since 2001, all registered canola seed treatments have included a neonicotinoid (Group 4A) active ingredient, creating the foundation for early-season flea beetle protection. Mori explains that because nearly all canola seed is treated with the same mode of action, ongoing monitoring is an important step in protecting this critical control method.

“We wanted to make sure seed treatment products were still doing their job and reducing flea beetle damage in canola fields,” he says, noting his team determined that neonicotinoid seed treatments remain an effective tool for protecting seeds and seedlings.

In addition to seed treatments, foliar insecticides — including pyrethroids — are typically used when flea beetle populations exceed economic thresholds. That’s why the project’s second objective focused on determining flea beetle susceptibility to these products.

This work surveyed flea beetle susceptibility to pyrethroids across the Prairies. Once again, the research found that foliar insecticides remain an effective management tool for flea beetle infestations.

“Tracking how populations respond to this chemistry group is important, particularly as foliar applications may be needed in high-pressure years,” notes Mori, explaining that understanding how both seed treatments and foliar products perform provides farmers with better information to make informed decisions in-season and can guide resistance management strategies to help preserve the effectiveness of these products.

Beneficial insects at work

While much of the project focused on insecticides and how well they’re working, it also highlighted an important ally already in canola fields: natural predators.

Throughout the 2021 and 2022 growing seasons, PhD student Aldo Ríos sampled 10 Alberta canola fields and collected nearly 82,000 insects to better understand which beneficial species are present and what pests they may be eating.

Ground beetles stood out as the dominant predator group. In particular, a non-native ground beetle, known only by its scientific name, Pterostichus melanarius, was the most common species found.

Lab research determined this beetle feeds on major canola pests, and further DNA testing of field-collected beetles confirmed they had consumed flea beetles.

“Not only did we confirm that these ground beetles can be a beneficial predator for flea beetles, but the advanced DNA techniques used to identify prey species in the predators’ guts can be used as a primer set for future research,” says Mori, explaining that through the research, his team was able to identify flea beetle DNA. “This valuable information will serve as a new research tool.”

While it’s still unknown if flea beetles are the Pterostichus melanarius ground beetle’s preferred prey, the research confirmed that the beetle actively feeds on at least some key pests in canola fields. And for growers, this matters because it suggests natural predators, also known as beneficial insects, may already be helping reduce pest pressure in the field.

Habitat matters

Researchers also observed that fields with grassy edges and tree-lined fence rows supported greater biodiversity, especially for insects. Mori notes that while flea beetle pressure is often higher along field edges, or headlands, predator populations tend to be higher there as well.

“These areas may provide habitat that helps beneficial insects survive and thrive, potentially strengthening natural pest control in surrounding crops,” he explains, noting that maintaining or enhancing field edges could be one way growers support beneficial insect populations while continuing to manage pests effectively.

The project focused on early-season flea beetle and predator populations, but Mori says more research is needed to understand what happens later in the season, too. In particular, he’s interested in late summer predators that could help reduce flea beetle numbers before overwintering, and potentially lower pressure the following year.

Supporting integrated pest management

Canola growers have long relied on insecticide seed treatments and foliar applications to manage flea beetles. Those tools remain important, but understanding which beneficial insects are present — and how they contribute to pest control — can help build a more complete integrated pest management (IPM) strategy.

Together, the resistance monitoring and predator research provide valuable insights for farmers across the Prairies. By tracking insect susceptibility and recognizing the role of beneficial insects, the industry can continue working toward sustainable, effective pest management.

“Beneficial insects are so important,” says Mori.

“Growers may not visibly see it, but they can contribute to crop yield by helping with natural pest regulations in the field, and some are even pollinators that work double-duty. And the best part is they don’t cost a thing.”

For growers, the takeaway is straight-forward: keep monitoring fields, use economic thresholds when making insecticide decisions, rotate active ingredients in foliar sprays, and consider how field management practices, including habitat conservation, can support both crop protection and long-term sustainability.

As flea beetles continue to challenge canola production, research like this helps equip farmers with the tools, knowledge, and confidence to protect their crops today and in the seasons ahead.

For more information about how beneficial insects work as key allies in crop protection and integrated pest management, or for tips on scouting, supporting and recognizing pests that make a difference in Prairie fields, visit fieldheroes.ca.

These projects were funded in part by the Canola Agronomic Research Program (CARP) including the Canola Council of Canada, Alberta Canola Producers Commission, SaskOilseeds, Manitoba Canola Growers Association, and Western Grains Research Foundation. Additional funding was provided by the Government of Canada’s Canadian Agricultural Partnership, Results Driven Agricultural Research, Natural Sciences and Engineering Research Council (NSERC), Bayer Crop Science Canada, and Syngenta Canada. BF