You may not have heard of the pepper weevil, but it’s said to have cost Ontario farmers $83 million in crop damage in 2016. Now, scientists hope a blast of cobalt gamma radiation will prove more potent – and less problematic – than pesticides in controlling the creature.
The researchers, from University of Guelph, will hatch pepper weevils in a lab and douse them with radiation from the isotope cobalt-60, produced at Ontario’s Bruce Nuclear power plant on Lake Huron.
James Scongack, Vice-President Corporate Affairs and Environment at Bruce Power, said the generating station produces the isotope for an Ottawa-based company that exports it for scientific and lab use.
“Cobalt-60 is used in sterilization of medical equipment and a range of other applications,” he told CBC Kitchener-Waterloo.
The weevil experiment will use the isotope’s gamma radiation for a different kind of sterilization, explained Cynthia Scott-Dupree, environmental science professor and the Bayer Crop Science chair in sustainable pest management at the University of Guelph.
“The [laboratory] insects are exposed to gamma radiation created by the Cobalt-60, and this results in sterilization of the insects,” she explained. “We release the insects we sterilize into areas that are infested by wild pepper weevils that continue to be fertile.”
When the sterile and wild insects mate, she explained, “the offspring aren’t viable: in fact, they don’t even hatch.”
“The result is the pest population eventually drops and there is no problem to contend with.”
Radiation versus pesticide
Ontario’s energy minister, Glenn Thibeault, has described the experiment as an “innovative, environmentally-friendly way to deal with agricultural pests that cause real harm to food crops.”
Scott-Dupree said controlling this particular pest with insecticides has proven difficult because much of the creature’s developmental life takes place inside the pepper itself.