The Effect of Diatomaceous Earth, Sodium Chloride, and Temperature on the Control of the Red Flour Beetle Tribolium Castaneum (Herbst, 1797) (Coleoptera; Tenebrionidae)

The red flour beetle [Tribolium castaneum (Herbst, 1797)] is a major secondary pest of stored wheat and flour, posing significant threats to both quantity and quality. In this study, we evaluated the effects of natural physical control methods, specifically temperature and humidity, on the larvae and adults of T. castaneum. A range of low temperatures (9, 11, 13, 15, and 17 °C) was tested in comparison to a warm control (31 °C), along with the use of Diatomaceous Earth (DE) and coarse salt (NaCl) to reduce ambient humidity in storage environments over five days. Results showed that DE and NaCl were particularly effective under cool conditions, with up to 80% mortality observed at 9 °C on the first day and complete mortality (100%) by day five. This preliminary study represents the first of its kind on Iraqi populations of T. castaneum, and offers promising insight for developing low-cost, sustainable and eco-friendly strategies for stored-product pest control.