A fungal biopesticide that shows promise for the control of bed bugs is highly effective even against bed bug populations that are insecticide resistant, according to research conducted by scientists at Penn State and North Carolina State universities.

UNIVERSITY PARK, Pa. — A fungal biopesticide that shows promise for the control of bed bugs is highly effective even against bed bug populations that are insecticide resistant, according to research conducted by scientists at Penn State and North Carolina State universities.

The study suggests that Aprehend, a mycoinsecticide developed at Penn State, likely will provide an important new tool for managing bedbug infestations, which have surged in recent years.

Nina Jenkins, senior research associate in entomology, College of Agricultural Sciences, Penn State, and her team have been working with entomopathogenic fungi, which have demonstrated effectiveness against other public-health pests, such as malaria vectors, cockroaches and house flies. Researchers also have shown fungal pathogens to be effective against insecticide-resistant mosquitoes.

"The goal of this study was to evaluate the efficacy of this product on an insecticide-susceptible lab strain of bedbug, and compare that to its effect on three field-collected strains known to be resistant to insecticides," Jenkins said. "We also compared mortality of these four bedbug strains after exposure to either a commercial pyrethroid insecticide or Aprehend."

The result was the development of Aprehend, a patent-pending compound based on Beauveria bassiana, a natural fungus that causes disease in insects. Previous studies have shown that the formulation can be applied as a long-lasting barrier treatment. Bedbugs that cross the barrier acquire fungal spores and go on to spread these among insects that remain in their harborages, resulting in greater than 95 percent mortality within a week.

The nonresistant bedbugs exposed to fabric treated with chemical insecticide sustained similarly high mortality rates. However, only 16 percent to 40 percent mortality was reached among the field-collected, resistant strains of bedbugs 14 days after exposure.

"In two of these resistant strains, survivorship after insecticide treatment was not significantly different from the control group," Jenkins said.

Source: Penn State University

