The insecticidal efficacy of Iranian diatomaceous earth deposits against adults of Callosobruchus maculatus F. (Coleoptera: Bruchidae)

The insecticidal efficacy of three Iranian diatomaceous earth (DE) deposits obtained from Maragheh, Mamaghan, Khorasan Jonoobi mines and a commercial formulation, Sayan®, was assessed against adults of Callosobruchus maculatus F. (Coleoptera: Bruchidae). Cowpea grains were treated with four concentrations including 200, 600, 1000 and 1500 mg/kg and each concentration replicated four times. Experiments were carried out at 28±1˚C and 55±5% R.H. in continuous darkness. The mortality was counted after 2, 5, and 10 days of exposure. After 10 days, all adults were removed from vials, and the vials were left at the same conditions for an additional 35 days, to evaluate the progeny production. The mortality percent increased with increasing concentration level and time exposed to each concentration. Mamaghan, Khorasan Jonoobi and Maragheh DE deposits have the most insecticidal toxicity against adults after 10 days of exposure, respectively. The concentration 1000 mg/kg of these DEs was sufficient enough to suppress C. maculatus progeny production. Therefore, Iranian DE deposits may be applied as a suitable tool in stored products pest management programs.