Impact of temperature on cumin fumigant toxicity and locomotor activity of Sitophilus granarius and Tribolium confusum adults

Essential oils have been used as alternatives to chemical pesticides. In this study, fumigant toxicity of cumin essential oil, Cuminum cyminum (L.) was investigated on the adults of granary weevil, Sitophilus granarius (L.) and confused flour beetle, Tribolium confusum Jacquelin du Val. Experiments were conducted at 25 ± 1 and 32 ± 1°C, 5 ± 55 relative humidity and darkness with four replications. Cumin essential oil was applied for S. granarius at the concentrations of 4, 7, 10, 13 and 16 µL L-1 air and in the case of T. confusum, 8, 11, 14, 17 and 20 µL L-1 air. Adult mortality was counted 24 and 48 hours after exposure. The results showed that an increase in temperature and exposure time increased both insects mortality. Also, S. granarius adults were more susceptible than T. confusum. Adult locomotor activity was studied at both temperatures by application SwisTrack version3. Distance and speed of insects when exposed to the cumin oil at a temperature of 32 ± 1°C was significantly more than cumin oil + 25 ± 1°C. Therefore, combination of essential oils and heat can be used in integrated pest management programs of stored products.