Morphological abnormalities in Tribolium castaneum (Herbst) and Tribolium confusum Duval due to cyromazine and pirimiphos-methyl treatments alone or in combination

Abstract

Newly hatched (24 h old) larvae of Tribolium castaneum and T. confusum were allowed to feed on different doses of cyromazine or pirimiphos-methyl, or on a combined dose of both compounds up to pupation. All the treatments produced deformities at all the life stages. Cyromazine produced a number of abnormalities in the larval stage (P < 0.001) of the two species. Both the compounds produced similar type of deformities in the adults, but the effect was slightly more in the female T. confusum. The combined action (10 ppm cyromazine + 0.1 ppm pirimiphos-methyl) of the compounds also produced deformities at each stage; and the effects were more pronounced than the effect caused by a single dose of either 10 ppm cyromazine or 0.1 ppm pirimiphos-methyl, and this will produce less stress on the environment and human health.

Keywords

• abnormalities
• Tribolium
• cyromazine
• pirimiphos-methyl