Bacterium could wipe out pest problem

It’s less than one-hundredth the size of a pinhead and sounds like a character from “Star Wars.”
But for western cattle producers, it could reduce pest problems that cost an estimated $7 million each year in Alberta alone.
Wolbachia is a bacterium under study at Agriculture and Agri-Food Canada’s Lethbridge Research Centre, where new DNA studies are shedding light on its unique role in nature and its dramatic potential to improve biological pest control strategies.
Early research has shown that wasps infected with Wolbachia can, under certain conditions, produce a much higher percentage of female offspring than uninfected wasps.
Scientists are investigating the potential of the bacterium to cause female-biased sex ratios in species of tiny wasps that are natural enemies of the house fly and the stable fly–two economically important pests of cattle.
Both the bacterium and the wasps occur naturally in Alberta.
Female wasps lay eggs in fly pupae. The eggs hatch and the wasp larvae feed on the developing fly.
These wasps eventually emerge as adults from the dead fly pupae and go on to repeat the cycle, killing more developing flies.
Because only females lay eggs, the effect of Wolbachia in producing more female wasps could provide increased fly control.
Researchers now are using molecular techniques to isolate and classify different strains of Wolbachia DNA to find the ones with the best potential.
Biocontrol is an important tool for integrated pest management (IPM), which involves the use of sanitation, chemicals, and natural enemies in varying combinations to give producers long-term, safe, and cost-effective pest control.
Because Wolbachia is widespread in many insect pests throughout the globe, this fundamental DNA research has broad implications.
Wolbachia is thought to infect 20-70 percent of all known insect species, and research into the bacterium has just started to develop in the last 10-15 years.
Researchers already have identified one strain of Wolbachia as causing female-biased sex ratios in parasitic wasps. The researchers hope to eventually find a strain that causes all-female offspring.
A “quirk” of wasp biology would allow all-female populations of wasps to persist generation after generation.
If Wolbachia could be used to produce a strain of wasps that produces only females, a great deal of time and money could be saved.
The ultimate goal is to use Wolbachia to produce all-female populations of wasps that then could be released to control flies.
It should be noted the wasps attack only flies and do not sting people or animals.