CONTROL OF 2 BRUCHID PESTS OF STORED GRAIN LEGUMES IN A NITROGEN ATMOSPHERE

The mortality of adults, eggs, larvae and pupae of the cowpea bruchid, Callosobruchus maculatus (F.) and the bean bruchid, Acanthoscelides o btectus (Say) in 100% nitrogen (N2) atmosphere at 25 and 32-degrees-C, respectively, and at 70 +/- 5% relative humidity, was investigated. I rrespective of temperature, all adults of both bruchids were killed wi thin 1 day of exposure to pure N2 atmosphere. All eggs were killed in 5 days at 25-degrees-C and in 3 days at 32-degrees-C. Complete mortali ty of larvae and pupae was observed in 9 days at 25-degrees-C and in 5 days at 32-degrees-C, except with young larvae of A. obtectus, which were all killed in 5 days at 25-degrees-C and in 3 days at 32-degrees- C. Exposure to an atmosphere of 100% N2 could therefore provide a rapi d means of disinfestation of stored grain legumes from C. maculatus an d A. obtectus.