It’s a bug-eat-bug world, says Assiniboine faculty member

Researcher uses $25,000 NSERC grant to reduce pesticide use.

Bugs that eat bugs fascinate Dr. Poonam Singh.

The instructor and researcher at Assiniboine Community College is studying the effectiveness of using “good bugs” to control pests that injure and sometimes kill plants.

Dr. Singh is the first instructor at Assiniboine to receive a grant from the Natural Sciences and Engineering Research Council of Canada – $25,000 from the NSERC Engage program.

Using “biological control agents” can reduce and even eliminate the need for spraying chemical pesticides on the plants, said Dr. Singh.

“Resistance is developed so fast in this pest world. Then you have to go to an even stronger pesticide. This is a pesticide treadmill. Once you are on it, you can never get off it. You are just paving the way for having stronger, more resistant pests,” she said.

“These biologicals, they are safe and economical. They provide a long-term solution. They’re very good for the customers, who don’t want pesticides on their plants. They’re good for the environment and they work really well.”

The bugs that are used to control the pests are either predators or parasitoids. Predators eat the pests. Parasitoids lay their eggs in the pests, killing them in the process.

“Eventually, when there are no more pests, the good bugs just die as part of their natural cycle.”

The practice of using biological control agents is already widespread in greenhouses used to grow vegetables. But many flower and shrub nurseries still use chemicals to kill pests as the cheapest way to protect plants from damage.

One of the requirements of the NSERC Engage grant is recruiting an industry partner who will benefit from the research.

Dr. Singh contacted Shelmerdine Garden Centre in Headingley, just west of Winnipeg, after hearing from a source in the industry that it was starting to use biological control agents in its greenhouses.

“They were very keen on getting this started, but they hadn’t been as successful as they had hoped,” Dr. Singh said.

“We are developing a customized integrated pest management program for them, using biological control agents. They told me they get almost 20 per cent economic loss because of the pests in their nursery. If we can somehow reduce plant damage using bio-control agents, it’s going to reduce their economic loss and increase their sales.”

Even though it was not required to, Shelmerdine committed $1,000 to the project. More importantly, it made in-kind contributions of plants and staff time. Dr. Singh has visited the garden centre many times, training greenhouse staff to run the program, while helping the marketing staff sell it to pesticide-wary consumers.

Shelmerdine vice-president Chad Labbe said his team has “really enjoyed working with Poonam and her students for this project. We have learned a tremendous amount during this process and look forward to learning more as the season continues.”

If the program at Shelmerdine is successful, Dr. Singh will make presentations to the Manitoba Landscape and Nursery Association, hoping to spread the practice throughout the industry.

The project is a great opportunity for students to “learn by doing,” Assiniboine’s motto.

One student, Tiffany Nykolyshyn, works on the project as a research intern, funded by the NSERC grant. Two other students work on the project as part of their course practicum. Dr. Singh has also taken the whole class from both her Sustainable Food Systems program and her Horticultural Production program twice to Shelmerdine to help identify and monitor the pests.

“The students will help us make decisions about implementing this program. They will be able to see the live implementation of this program. And they will learn from this real-world situation.”

Dr. Singh first piloted her program by pitting good bugs against bad ones inside the sustainable greenhouse at the college’s North Hill campus in Brandon, with students helping to initiate the program.

That part of her research was funded by Growing Forward 2, a federal-provincial program recently renamed the Canadian Agricultural Partnership.

Thrips, a common pest, lay their eggs inside leaves, hatch as larvae and eat the leaves, pupate in the growing media and emerge as adults to lay more eggs.

A mite known as Amblyseius cucumeris “is a very effective predator. She will eat both adults and larvae, although her preferred stage is larvae.”

When the thrips pupate inside the growing media, they can be attacked with small worms, known as entomopathic nematodes or Steinernema feltiae.

“They get inside and reproduce and eat everything inside the pupae. The pupae will be dissolved and these nematodes will be released and increase in number,” Dr. Singh said.

When the mites had so many larvae available that they didn’t want to eat the adult thrips, Dr. Singh introduced the Minute Pirate bug, Orius insidiosus.

“This bug specifically goes after thrip adults. When the thrips are not there, she feeds on pollen and survives on that.”

Dr. Singh began rearing her own beneficial insects inside the college’s sustainable greenhouse, which provides the perfect environment for her research, she said.

Her future research projects may include the study of “biofertilizer” – using the waste products from organic materials to enhance plant health.

Photo: Assiniboine agriculture instructor Dr. Poonam Singh, right, discusses how good bugs can fight bad bugs with, from left, Assiniboine student Gopin Patel, Shelmerdine employee Stephanie Walker and Assiniboine research intern Tiffany Nykolyshyn.