Nanotech may be the future of precision crop protection

In just a few years, crop spraying could become largely a thing of the past. Nanotechnology may take its place using its ability to target specific crop pests.

Farmers hear a lot of such whizzy claims. But a Lethbridge researcher is so confident in nanotech-based crop protection that he’s working to ensure it doesn’t follow the same regulatory route as GMOs.

“I’m pretty optimistic that by the end of the decade there will be something commercially viable,” said Justin Pahara, a scientist with Agriculture and Agri-Food Canada in Lethbridge.

He is working with nanoparticles that bind to agricultural pests such as lygus bugs and cutworms, two species he’s selected as initial targets. The tiny particles do so without harming beneficial plants and insects.

His bigger goal, however, is to create crop treatments that tackle the resistance, international trade and environmental hassles that conventional pesticides so often present.

“All of this is putting pressure on us to create new crop treatments that are less toxic and more species-specific so they don’t impact broader ecosystems,” said Pahara.

The scientist also sees opportunities for producers to expand market reach to countries where regulations prohibit the sale of products treated with conventional pesticides.

“If we get this right, there are so many possibilities for Canadian producers to differentiate themselves from everyone else, beyond just managing pests and whatnot.”

At its simplest, nanotechnology is the science of manipulating extremely small objects called nanoparticles.

“Human hair, if we put it in nanometres, is about 100,000 nanometres across. A nanostructure is typically one to 100 nanometres in size,” said Pahara.

“They’re bigger than a typical small molecule such as a water molecule or carbon dioxide molecule or even the molecules in typical broad spectrum pesticides.”

Medical foundation

Although Hollywood tends to approach nanotechnology as something close to science fiction, its real-world effectiveness has been proven in the biomedical sphere, where it’s been used and refined for decades.

For example, those who received a COVID-19 vaccine have already had experience with nanotechnology. In it, nano lipid vesicles carried the vaccine into human cells.

The medical world’s use of nanotechnology has given scientists a platform on which to build agricultural applications, said Pahara. But the principles of nanotechnology in medicine can be lost when carried into ag. That’s a challenge for researchers.

“For example, in the world of health care you can take a medicine, put it in a needle and inject a person so the ingredients go directly to the source of where they need to go.

“In the ag sector, we can’t expect a producer to be out in the field with syringes injecting all their plants or insects. We don’t have that same benefit so that adds extra complexity to what we’re trying to achieve.”

The key to Pahara’s work is identifying the right combination of nanoparticle and active ingredient, in this case DNA and RNA, that will target the specific part of a pest where it will be most effective.

Tightly targeted

This specificity separates these nanostructures from conventional pesticides, which generically attack a target as well as desirable organisms that happen to get in the way.

“For example, imidacloprid is a very common insecticide that’s more or less a neurotoxin to insects. It mimics nicotine and you’re basically targeting the nervous system of the insect,” he said.

“But many different insects and animals have nervous systems, so to some extent this small molecule has a very, very broad impact across many different systems.”

Pahara and company have not discovered a crop treatment for lygus bugs and cutworms. They’re still building the required technology.

However, if successful and proven safe, the possibilities are theoretically endless. That would set the stage for developing similar treatments for a host of insects and weeds.

“One thing that nanotechnology allows us to do is control and create larger molecules that have added functionality. That allows us to build in more control measures and have more flexibility in what sort of activity and outcomes we want these devices to have.”

Right rules

Before that, Pahara wants to ensure the environmental and human safety of nanotech-driven pest controls so they don’t face the same regulatory scrutiny as GMOs. He serves as chair of a Standards Council of Canada working group focused on the environmental health and safety of nanotechnology.

“We’re participating in international projects that aim to create standard methods that help scientists and regulatory bodies rigorously identify whether certain nano systems are toxic or not to the environment.

“We’re trying to start it now, while we’re in the early phases of the actual technology development.”

If or when a nanotech-based crop treatment arrives on the market, Pahara is excited at the possibility of being part of a made-in-Canada and made-in-Alberta success story.

“Western Canada could have some bragging rights here.”

– This article was originally published at the Alberta Farmer Express.