ARS | Publication request: DEVELOPMENT AND SURVIVORSHIP OF IMMATURE ANGOUMOIS GRAIN MOTH (LEPIDOPTERA: GELECHIIDAE) ON CORN

Submitted to: Environmental Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 3, 2004
Publication Date: August 31, 2004
Citation: Perez Mendoza, J., Weaver, D.K., Throne, J.E. 2004. Development and survivorship of immature Angoumois grain moth (Lepidoptera: Gelechiidae) on corn. Environmental Entomology V.33(4):807-814.

Interpretive Summary: The Angoumois grain moth is a cosmopolitan pest of stored corn, wheat, rice, barley, sorghum, and other cereals. Despite the importance of this pest, quantitative data describing its life history over a range of environmental conditions at which it will develop are lacking. Therefore, we studied the survivorship and duration of immature development of this moth on corn stored over the range of temperatures and relative humidities at which the insect can survive and develop. Temperature had the greatest effect on development and survivorship of immature Angoumois grain moths. The ideal environmental conditions for growth and development were within the range of 25-30 degrees C and 60-75% RH. However this insect has the ability to complete development at 15 or 35 degrees C and 43% RH. Our data can be used to define optimal storage conditions for avoiding Angoumois grain moth damage and to develop simulation models that can be used to optimize pest management strategies.

Technical Abstract: Life history of immature Angoumois grain moths, Sitotroga cerealella (Olivier), was studied at 10, 15, 20, 25, 30, 35, and 40 degrees C and at 43, 60, 75, and 85% RH under laboratory conditions. At 10 and 40 degrees C, none of the stages survived at any relative humidity. Temperature was the main factor affecting egg incubation period, larval development time, and egg and larval survivorship. The shortest egg development times occurred at temperatures of 30 C degrees and higher, but increased sharply as temperature decreased. Larval development time was shortest at 30ºC. Survivorship was optimal at 30ºC for eggs and larvae, but larval survivorship decreased sharply at 35ºC. Duration of larval development did not vary with sex. Newly-emerged females were two-fold heavier than males, and temperature and relative humidity did not affect weight. Sex ratio of emerging adults did not differ from 1:1 at any temperature or relative humidity. The optimum conditions for growth of Angoumois grain moth on corn were 30 degrees C and 75% RH. The data will be useful for determining safe storage conditions for corn and for developing a computer model for simulating population dynamics of immature S. cerealella.