Susceptibility of different life stages of saw-toothed grain beetle Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae) to modified atmospheres enriched with carbon dioxide.

摘要

The susceptibility of the different life stages of the saw-toothed grain beetle Oryzaephilus surinamensis to different modified atmospheres (MAs) containing various concentrations of carbon dioxide (CO 2) was studied as an alternative to methyl bromide fumigation at 30degreesC and 655% relative humidity (r.h.). The tested MAs were 55%, 65%, 75% and 85% CO 2 gas in the air. Mortality (%) was recorded after exposure periods of 3, 6, 12, 24, 48, 72 and 96 h. Larvae and adults were more susceptible while eggs and pupae were more tolerant to CO 2. A two-day exposure period was adequate to completely kill larvae and adults under all tested MAs. All eggs and pupae were killed after four days of exposure to the high-CO 2 atmospheres (75% and 85%).