Abstract
The effectiveness of carbon dioxide for use as an insecticide was examined by exposing adults and larvae of the western flower thrips (Frankliniella occidentalis) to high concentrations of the gas. Treatment of adults with 20 to 30%CO2 for 24h at 24°C resulted in a proportional increase in mortality, reaching 100% at 30%CO2 or higher concentrations. The time required for 100% mortality at 60%CO2 was less than 24h at 24°C, less than 10h at 30°C, and less than 4h at 34°C. The findings indicated that mortality increased in proportion to carbon dioxide concentrations and treatment temperatures, and that this tendency was common to adult and larval stages. It therefore seems advisable for treatment with high concentration CO2 to be applied to nursery systems for “thrips-free seedlings.”
