Some effects of a mixture of oxygen, carbon dioxide and nitrogen in the ratio 1:1:8 on the oviposition and development of Sitophilus zeamais Mots. (Coleoptera, Curculionidae)

Abstract

The emergence pattern of Sitophilus zeamais Mots, adults from whole grain maize was monitored following oviposition in air or the gas mixture with development continuing either in the same or the alternative atmosphere. After exposure to the gas mixture during oviposition only, development only, and during both, the numbers of adult offspring per female were about 40, 50 and 20° o respectively of those obtained from the controls in air. In addition continuous exposure to the gas mixture during development resulted in a delay of 10–11 days in the mean developmental period. No significant difference was found between the results obtained when the insects were kept in air throughout and when oviposition only took place in pumped air or in air on maize equilibrated in the gas mixture before use.