The Indianmeal moths are the most economically important pest of stored grains. All the larval stages of this moths infest and feed on the germs of different kinds of cereal and rice grains. All the larval stages also directly feed on the processed dry foods like pasta, bread and spices. Indirect damage caused by the Indianmeal moth larvae include contamination of grains with their droppings as well as spinning of silk webs in the grains. This indirect damage reduces the marketability of the grains. Although, adult moths do not cause any type of damage to the grains, they are a nuisance to home dwellers.
Females of the Indianmeal moth lays eggs singly or in groups of over 20 eggs on the surface of the grains. These eggs hatch within 15 days into small larvae that start feeding on germs of grains. While feeding, larvae pass through 5- 7 developmental stages before maturity. Matured larvae then spin silk cocoons on the grains, on the walls of bins and then pupate inside the cocoons. Adult moths emerge from pupae with 2 to 30 days. These moths can complete their life cycle within 30 days. Depending on the temperature, they can complete 8-9 generations in a year.