effect of controlled atmospheres (cas) at various concentrations of co2, n2 and o2 on the lethal times of tribolium castaneum and trogoderma granarium was investigated at 20 and 30 ºc. experiments were performed using a recirculatory multi-flask apparatus. the results revealed that, the shortest times (0.1, 0.3 and 0.9 day for adults, larvae and pupae, respectively) required to obtain 50% morta...