Sensitivity of the red flour beetle to some inert dusts

Abstract

In this study six types of Inert dusts, (aqueous copper sulfate, silica gel, calcium, garcol, magnesium carbonate and celite)were tested against red flour beetle Tribolium castaneum (Herbst) after treatment of wheat flour with the dusts, at 5 and 10% concentrations. The silica gel and celite powders showed superior efficacy than the other powders in both males and females, 94, 80% mortality for silica gel and 90,92% for celite respectively. The results showed that females exposed to powder, water copper sulphate has the highest number of eggs were 37.5 eggs per female when silica gel put less number of egg was 16.3 compared to the treatment as the control females laid 56.6 eggsThe results showed that the silica gel and celite clearly impact the development of the insect in comparison to the other powders which is decreasing the larval stage 12.4 and 7.0 for concentrations of 5 and 10% for silica gel powder ,and 12 and 8.0 for powder celite compared to control treatment of 24 days. As well as the duration of pupal stage reached 5.6 and 4.8 days for powder silica gel to 4.6 and 3.6 days for the celite, while the control reach to 9.5 days, and thus a development of 20 and 11.8 days, and 16.6 and 13.4 days for both powders and concentrations respectively, compared to the control treatment 33.5 days. The dusts also shortened the life period of the insect treatment compared to control. Powders have affected both the number of eggs and the incubation period decreased as the incubation period was less in copper sulfate powder, 3.8 days than in the control treatment 7.0 days. Results revealed that increasing of powder concentration used resulting in the increasing of its effect on growth and development of the insect.Key words: red flour beetle. Tribolium castaneum, inert dusts.