Fumigant effect of carbon dioxide and ammonia gases on adults of Callosobruchus maculatus and Sitophilus granarius

 Callosobruchus maculatus and Sitophilus granarius are two of the most important pests of stored products and cause heavy damage. Due to economic importance of stored product pests and resistance potential of them to conventional fumigants, it is necessary to replace these insect control agents with novel and safe compounds. Modified atmosphere is a valuable method to control some stored product pests. In this research effect of this method based on the use of carbon dioxide and ammonia was evaluated against adult stages of C. maculatus and S. granarius alone and in combination with each other in glass anaerobic jars. Mortality was recorded after 24 h. The LC50 values of carbon dioxide for C. maculatus and S. granarius were estimated 1322.53 and 1283.96 ppm, respectively. The LC50 values of ammonia for these pests were estimated 250.24 and 366.79 ppm, respectively.The mixture of carbon dioxide and ammonia (in LC25 values) caused a mortality rate of 86.67 and 93.33 % on the adults of C. maculatus and S. granarius respectively. The effects of carbon dioxide and ammonia were also evaluated against germination rate of cowpea and wheat seeds at 2238.72, 3630.78 and 426.58, 549.55 ppm, respectively. Germination rate was up to 98 percent.