Toxicity of High Oxygen Atmospheres to Tribolium castaneum (Coleoptera: Tenebrionidae)2

Abstract

Adults, larvae, and pupae of Tribolium castaneum (Herbst) were exposed to atmospheres containing 70%, 80%, and 90% O2 for 7, 14, 21, and 28 days. Ninty-nine percent morality of adults was obtained after 21 days at 90% O2, while a maximum mortality of 80 and 38% was achieved after 28 days at 80% and 70% O2 respectively. The effect of O2 on larvae was found to be greater than on pupae: 100% larval mortality was obtained at 90% O2 after 14 days while complete mortality was achieved with pupae after 28 days. After treatment with high O2, the appearance of abnormal insects as well as effects on their life cycle were observed. When larvae were treated for 14 days at 80% O2, only a few individuals developed to adults. No larvae reached the adult stage after exposure to 90% O2 for 14 days. In all treatments, except those conducted at 90% O2, insects exposed as pupae developed into adults.