Using nanotechnology to target crop-munching pests and spare beneficial bugs

A bane of farmers’ existence, it’s estimated that plant-eating pests are responsible for the loss of up to 40% of pre-harvest yields globally. But a new generation of crop treatments that target only “bad” bugs could mean big gains for the Canadian agriculture sector, improving pest management tools in an industry that in 2024 generated over $142 billion.

Dr. Justin Pahara and his team at Agriculture and Agri-Food Canada’s (AAFC) Lethbridge Research and Development Center are designing new screening methods to learn whether current crop treatments are effective. Their end goal, however, is to develop a method for using nanotechnology to deliver specific chemicals into pests based on their unique DNA—without harming helpful insects.

For example, through methods developed and tested at the Canadian Light Source (CLS) at the University of Saskatchewan, the researchers found that lygus bugs contain regions of enriched minerals pointing to certain proteins that could one day be targeted with tailored agents to prevent them from eating crops. The lygus bug is a common agriculture pest that feeds on many crops, including canola. Pahara and his team’s innovative methods are published in the Canadian Journal of Chemistry.

“We all need food, and if farmers cannot grow their products efficiently and make a living out of it, it’s a problem,” says Pahara. “We need new tools for pest management. Insects are becoming more tolerant to chemicals in the same way antibiotic resistance works in humans.”

Developing targeted pest treatments would also make “carpet bombing” insects with harmful pesticides a thing of the past.

“The ‘spray-and-pray’ approach ends up also killing beneficial bugs such as pollinators, and predatory insects like spiders, wasps, and beetles that help maintain a healthy ecosystem,” says Pahara.

The first step was to study how pesticides get into pests in the first place, how the nanomaterials get into their bodies and where the substances accumulate, information that will help design better solutions.

Pahara and his team used the BioXAS beamline at the CLS to create X-ray images of cutworms and lygus bugs, showing what chemicals were present in the insects and where.

Then, the group developed special software to explore the bug images in 3D models using virtual reality, so they can take an even “closer look” at the inside of the insects’ bodies.

“Designing new approaches is a very challenging problem and people have been working on it for decades, but with little success,” says Pahara. “Ultimately it’s our job at Agriculture and Agri-Food Canada to pass on what we learn to Canadian industry to solve key technical problems so industry can take over with less risks.”

Now that Pahara and colleagues know their screening test works, they are expanding their research to weeds and fungi pests and will be able to start testing the delivery of nanomaterials developed by both AAFC and the NANO division of the National Research Council of Canada into insects’ bodies.