Larval and adult Tribolium confusum were tested in flour and sand substrates at various relative humidities, ranging from 10% to 90%. Both life stages preferred a flour environment of from 10% to 50% relative humidity. In sand, however, the insects selected more humid environments. Investigations of survival in sand, flour, and air environments indicated that two factors may be operating in the...

Late-instar larvae, pupae, and adults of Tribolium castaneum (Herbst), the red flour beetle, or Tribolium confusum (DuVal), the confused flour beetle, were exposed for variable durations at 36–54 1C. Beetles were placed in laboratory ovens set at a baseline of 27 1C, the temperature was increased by 0.1 1C per minute until the target temperature was achieved, and beetles were then held for spec...

Humans and animals come into contact with various compounds in their natural environment. Most of the encountered substances are neutral, yet some may carry adverse health effects. The ingested food may be a source of harmful substances, including benzoquinones which, as shown by research results cited in this paper, demonstrate toxic, carcinogenic and enterotoxic activity. This group of compou...

Bioassays were conducted to assess the contact toxicity of two plant essential oils against adults of Sitophilus granarius (L.) and Tribolium confusum Jacquelin du Val. Essential oils were extracted from seeds of Carum copticum L. and Cuminum cyminum L. Contact toxicity was assessed by topical application and adult mortality was counted 1, 2, 6 and 24 h after exposure. Bioassays were carried ou...