Oxygen sensitivity in the insect Prodenia eridania

¹ Department of Biological Sciences, University of Delaware, Newark, Delaware

Both the larval and pupal stages of prodenia eridania are injured by oxygen at increased pressures. The injury is manifested by a reduction in the rate of oxygen consumption, muscular paralysis and failure to develop to the adult stage. In the pupae these effects appear together as a syndrome. Pupae are much more sensitive than larvae. At least 75 psi of oxygen is necessary for injury to larvae while only 45 psi is required to produce injury in the pupae. Injured pupae respire at a rate 2%–5% of the controls while the injured larvae consume oxygen at 60% of the control rate. In attempts to modify this sensitivity by pretreatment with agents which reduce the metabolic rate, it was found that pupae kept at –10°C for 30 minutes before treatment or kept in carbon monoxide or nitrogen for 30 minutes prior to treatment showed none of the injurious effects of oxygen.