Effect of Temperature on the Competitiveness of Three Stored Product Insects

Competitiveness is an important feature in insect biology. Three srtored product pests viz., Trogoderma granarium, Tribolium castaneum, Oryzaephilus surinamensis were evaluated for their competitiveness at 35, 25 and 40°C. The results revealed that within 6 months, T. castaneum and O. surinamensis could not displace the T. granarium, but at 35 °C, T. granarium was able to displace the O. surinamensis. It was found that T. granarium at 25 °C continued to be dominant for long periods without being affected by other species. It was in the dormant larval or egg stage despite the death of all adults, and the increased at 40°C.