Beneficial Wasp to Protect U.S. Stored Commodities
By Linda McGraw
October 10, 2000
A key to improving the quality of U.S. stored commodities may be a
beneficial parasitic wasp that attacks the larvae of many agriculturally
destructive moths. Agricultural Research Service scientists are studying
Habrobracon hebetor, an external-feeding parasitic wasp used to control
the Indianmeal moth, the most prevalent and damaging insect pest in stored
commodities. ARS is the chief scientific
research agency of the U.S. Department of
The Indianmeal moth and other agricultural insect pests have
developed widespread resistance to Bacillus thuringiensis, or Bt,
which means that synthetic pesticides must be applied to control them. But the
same pests are also developing resistance to currently used pesticides, and
regulatory restrictions are limiting the use of others. Thats why new
biocontrol methods are under scrutiny at ARS Grain Marketing and Production
Research Center in Manhattan, Kan.
The H. hebetor wasp is a good biocontrol agent partly
because it feeds rapidly and has gut enzymes that quickly break down two major
blood proteins in moth larvae. It is already commercially available for pest
management programs, but it would be more economical to produce if artificial
diets were available.
ARS entomologist James E. Baker and doctoral student Jeffrey
Fabrick have described the digestive processes of these parasitoids when
feeding on the blood of paralyzed Indianmeal moth larvae in the laboratory.
Their findings were published in Insect
Biochemistry and Molecular Biology (October 2000). Baker will present
the information at a joint meeting of the
Quebec Entomological Societies and the
Entomological Society of America in
Montreal, Dec. 3-6.
Stored-product insects can be a major problem in grocery, health
food and pet stores and in home food pantries. Infested products can include
birdseed, peanuts, pecans, dog food, candy, macaroni, breakfast cereals, corn
meal, bread and dried beans. This research will aid in the development of an
artificial diet for economically rearing this promising potential
Scientific contact: James E. Baker, ARS Grain Marketing
and Production Research Center, Manhattan, Kan., phone (785) 776-2785, fax
(785) 537-5584, email@example.com.