Left: Red flour beetle larvae exposed to concrete treated with the insect growth regulator hydroprene failed to grow to adulthood. Right: Healthy adults on untreated concrete. Click image for additional information.

Read the magazine story to find out more.

Protecting Perishables From Package Pests

Insects that invade and penetrate packaged foods really bug store and homeowners. Packages can become infested anywhere along the marketing chain, but most often they get infested during transporting or warehousing. Naturally, manufacturers of food, feed and other processed products prefer these unwanted guests to go packing.

As an alternative to traditional insecticides, Agricultural Research Service entomologist Franklin H. Arthur at the Grain Marketing and Production Research Center in Manhattan, Kan., is conducting new research with insect growth regulators (IGRs) that severely stunt bugs' growth. IGRs prevent insect larvae from becoming reproductive adults.

To replicate food-storage conditions, Arthur creates miniature “exposure arenas” by pouring concrete into petri dishes. Once the concrete hardens, he sprays the IGRs directly onto the concrete and then exposes the insects to the treated concrete.

Since IGRs are not normally toxic to humans, they can be used to banish packaged-food pests, such as the red flour beetle and the confused flour beetle. Arthur recently evaluated just what effect a volatile formulation of the IGR named hydroprene has on the bugs. In lab tests, larvae of both beetle species exposed to hydroprene (sold as Pointsource) often failed to molt to the adult stage. Of the insects that made it past the stunted-growth hurdle, most were deformed and died soon after.

Use of Pointsource could be most effective in small, confined spaces in retail stores and homes.

This research is important because food manufacturers face increased restrictions for using pesticides. Still, they need to keep packaged foods insect-free until consumed.

Read more about blocking bugs in the January issue of Agricultural Research magazine.

ARS is the U.S. Department of Agriculture’s chief scientific research agency.