Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: DEVELOPMENT OF QUARANTINE ALTERNATIVES FOR SUBTROPICAL FRUIT AND VEGETABLE PESTS Title: Ionizing Irradiation of Adults of Angoumois Grain Moth (Lepidoptera: Gelechiidae) and Indianmeal Moth (Lepidoptera: Pyralidae) to Prevent Reproduction and Implications for a Generic Irradiation Treatment for Insects

Authors
item Hallman, Guy
item Phillips, Thomas - OKLAHOMA STATE UNIV.

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 24, 2008
Publication Date: August 15, 2008
Citation: Hallman, G.J., Phillips, T.W. 2008. Ionizing irradiation of adults of Angoumois grain moth (Lepidoptera: Gelechiidae) and Indianmeal moth (Lepidoptera: Pyralidae) to prevent reproduction and implications for a generic irradiation treatment for insects. Journal of Economic Entomology. 101:1051-1056.

Interpretive Summary: Irradiation is used as a quarantine treatment. A generic treatment dose of 400 Gy was approved by APHIS for commodities entering the United States for use against all insects except pupae and adults of the moth and butterfly order (Lepidoptera) because some studies indicate that a few of these, such as the Angoumois grain and Indianmeal moths, are not completely controlled at 400 Gy. Tolerance to radiation in insects increases as they develop, so the minimum radiation dose to prevent hatch of eggs laid by these two grain moths when irradiated as adults was studied. Also, because low oxygen storage is known to increase radiotolerance in insects, Angoumois grain moth was tested in a low oxygen condition as well as air. A dose range of 336-388 Gy prevented egg hatch from a total of 22,083 adult Indianmeal moths. Dose ranges of 443-505 and 590-674 Gy, respectively, prevented egg hatch from a total of 15,264 and 13,677 adult Angoumois grain moths irradiated in air and low oxygen. A generic dose of 600 Gy for all insects in air might suffice, although many fresh commodities may not tolerate the dose when applied under commercial conditions.

Technical Abstract: Ionizing radiation is used as a phytosanitary treatment against quarantine pests. A generic treatment of 400 Gy has been approved for commodities entering the United States for use against all insects except pupae and adults of Lepidoptera because some literature citations indicate that a few insects, namely the Angoumois grain moth, Sitotraga cerealella (Olivier), and the Indianmeal moth, Plodia interpunctella (Hubner), are not completely controlled at that dose. Radiotolerance in insects increases as the insects develop, so the minimum absorbed dose to prevent F(1) egg hatch for these two species when irradiated as adults was examined. Also, because hypoxia is known to increase radiotolerance in insects, Angoumois grain moth radiotolerance was tested in a hypoxic atmosphere. A dose range of 336-388 Gy prevented F(1) egg hatch from a total of 22,083 adult Indianmeal moths. Dose ranges of 443-505 and 590-674 Gy, respectively, prevented F(1) egg hatch from a total of 15,264 and 13,677 adult Angoumois grain moths irradiated in ambient and hypoxic atmospheres. A generic dose of 600 Gy for all insects in ambient atmospheres might be efficacious, although many fresh commodities may not tolerate it when applied on a commercial scale.

Last Modified: 9/10/2014
Footer Content Back to Top of Page