Effect of temperature on stored product pests Tribolium confusum Jaquelin du Val (Coleoptera: Tenebrionidae) and Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchidae)

Abstract

Two stored product insects, Tribolium confusum and Callosobruchus maculatus were exposed to different temperature degree (50, 55, 60, 65, 70 and 75 C) and different exposure periods (10, 15, 20, 25, 30, 35 and 40 minutes). Increase in temperature level or exposure time resulted in an increase in average mortality. Complete mortality of T. confusum was achieved in 50, 55, 60, 65, 70 C at 25, 20, 15, 15 and 10 minutes of exposure times respectively. 100% Mortalities of C. maculatus was achieved in 50, 55, 60, 65, 70 and 75 C at 40, 25, 25, 20, 15 and 10 minutes of exposure times respectively. Loss percentage of wheat flour and emergence percentage of adult insects were significantly decreased (P˂0.05) with increasing of temperature levels and exposure times. There was no significant effect of temperature and exposure time on cowpea seeds germination which concluded that Thermal disinfestation is one of the means of physical insect control.