Researchers put bees to work

Bee vectoring | Bees used to distribute biological control agents

A researcher who has used bees to distribute biological control agents in greenhouses and organic sunflower fields says the technology has potential in other field crops, including canola.


Peter Kevan of the University of Guelph is one of several researchers in Ontario who have worked with bee vectoring over the last two decades, using managed populations of bumblebees to help suppress plant diseases and insect pests.


Bees collect a control agent on their legs and bodies as they pass through a dispenser attached to beehives and eventually shed it as they forage and pollinate plants.


He said the application method could work in canola production, which is commonly associated with honeybees in Western Canada.


“We expect that we’ll be able to develop a technology which will certainly be able to protect canola crops against sclerotinia and insect pests, but at the moment we haven’t gotten so far as to say whether using bee vectoring on those crops would be cost effective,” said Kevan.


The technique isn’t new, but recent steps have brought the application method closer to mainstream commercial production. 


The Pest Management Regulatory Agency has approved the delivery method in greenhouses for Botanigard 22WP, a biological insecticide based on the fungus beauveria bassiana, while Bee Vectoring Technology looks to commercialize related technology.


“We’re constantly trying to move ahead here and show that this is sort of like the tip of the iceberg, so to speak,” said Les Shipp of Agriculture Canada, who has worked with bee vectoring in greenhouse studies. 


“There’s a lot of potential.”


Studies using Botanigard have determined the concentrations required to manage whitefly and tarnished plant bugs on greenhouse tomatoes and sweet peppers. The results are encouraging, providing acceptable yield and quality. 


The method also allows growers to reduce labour costs because the bees continually spread the agent, reducing the need for multiple spray applications of chemical pesticides. 


“All the different horticultural crops, people are actually now moving a little bit, too, as seeing the advantage of using commercial bumblebees as opposed to just using the native pollinator,” said Shipp.


Work is ongoing in greenhouse and field trials on fruit crops and sunflowers. Commercial trials on organic sunflower crops in Ontario, using a separate agent, have shown a significant yield boost while providing sclerotinia control, said Kevan.


“Although this technology can be used in an organic setting, it doesn’t have to be used in an organic setting,” he said. 


“It looks as if the cost effectiveness of this technology is certainly competitive, perhaps even cheaper, than the usual fungicide treatments that organic growers would not be allowed to use.” 


Field trials were conducted with honeybees 10 years ago to deliver beauveria bassiana to canola fields in Ontario to control lygus bugs, but more work is required, said Kevan. 


He said the project needs funding and partners, but researchers must also tailor the technology to the needs of honeybees if it is ever to be adapted in the West.


Kevan said he hopes to do further work with canola over the coming growing season, while also introducing the technology to sunflower growers in Manitoba.


“We’ll have to wait and see where things go on the canola front but we’re working on it and we should have a lot of information out by the end of this summer,” he said.