Development of Indian meal moth Plodia interpunctella (Hübner) inside finished products with low moisture content

Abstract: The possibility of Indian meal moth Plodia interpunctella (Hübner) development inside the finished products with low moisture content was investigated. The Indian meal moth population used in the study was obtained from various moth-infested commodities and maintained in laboratory conditions. The nutrient media was the salted powdered mixture which contained dried minced vegetables. The concentration of salt in the mixture was 50% minimum, and concentration of dried vegetables was 10% minimum. Maximum concentration of moisture in the food did not exceed 2%. The samples were divided in four categories in relation to different packaging materials and different quantity of packaged food. The samples were infested with 10 eggs per sample and incubated at two temperatures, 30 °C and 22 °C. Three samples of each category and from each temperature were opened monthly, during the test period of 10 months. The possibility of growth and development of Indian meal moth in the finished product of salted powdered mixture with dried minced vegetables, in both of tested temperatures, will be shown. The percentage of egg hatching varied from 72.91% to 94.61%, but the percentage of development from egg to adult were considerably lower and varied from 0% to 53.97%, depending on the quantity of packaged food and the incubation temperature. The possibility of growth and development of Indian meal moth was the highest in the samples with small quantity of nutrient media, and declined with the increase of the quantity of packaged food. Temperature of 30 °C resulted in higher percentage of found larvae and adults in food samples, compared to samples incubated in the room temperature.