The effect of nitrogen and carbon dioxide on eggs of Ephestia cautella (Walker) and E. kuehniella Zeller (Lepidoptera: Pyralidae)

Abstract

AbstractSome eggs of Ephestia cautella (Wlk.) and E. kuehniella Zell. hatched after exposure to near 100% atmospheres of nitrogen (N2) or carbon dioxide (CO2) for up to 5 days at 15°C, 3 days at 20°C and 1 day at 25°C. The most tolerant age at the start of treatment at 25°C in E. cautella was 7–24 h after oviposition for CO2 and 7–30 h for N2. Generally, hatch was lower in CO2 than in N2 whatever the exposure, and lower for E. kuehniella than for E. cautella. Considerably more eggs of E. cautella aged 30 and 42 h hatched after exposure to N2 than to CO2, showing a toxic effect of CO2 in the absence of oxygen. Eggs of both species treated with either CO2 or N2 hatched 1–2 days later than controls, regardless of age or percentage survival.