The effect of temperature management on Sitophilus zeamais, Tribolium castaneum and Plodia interpunctella in stored maize: summer 2001 pilot bin trials.

Abstract

AbstractThe use of three temperature management strategies (ambient aeration, chilled aeration and no aeration) for the control of the populations of S. zeamais (maize weevil), T. castaneum (red flour beetle) and P. interpunctella (Indian meal moth) was evaluated. Chilled aeration maintained the average grain temperatures between 11.5 and 17.1°C, which were effective in controlling populations of caged maize weevil and development of red flour beetle. Maize weevil population increased by 32% from June to September, while bins with no aeration (average grain temperatures between 15.1 and 27.4°C) and ambient aeration (average grain temperatures between 13.8 and 24.9°C) increased the population by 464 and 554%, respectively. For the Indian meal moth, maintaining lower grain bulk temperatures through chilling retarded the life cycle of the moth from egg to adult. The likely causes were delayed hatching of larvae from eggs and larval diapausing, which is an adaptation to survive low temperatures. Degree-day values based on a threshold development temperature of 15°C (59°F) for no aeration, ambient aeration and chilled aeration were 126, 126 and 48, respectively. The lower degree-day values for the chilled bins correlated to the lower insect counts observed in the maize weevil, red flour beetle and Indian meal moth cages. Our results showed that temperature management was an effective non-chemical and sustainable pest control method for stored product protection (average grain temperatures between 15.1 and 27.4°C).