Abstract: Flight capacity and triglyceride utilization of the beet armyworm, Spodoptera exigua adults during flight at temperatures from 16℃ to 32℃ were investigated. The moths flying at 24℃ exhibited the greatest flight distance and longest flight duration although they could fly normally at all temperatures tested. Adult flight capacity significantly declined at temperatures below 20℃ or above 28℃.These results suggested that the temperature most suitable for their flight be about 24℃. Utilization of energy substrate by the moths during flight was greatly affected by ambient temperature. Variations in flight capacity of adults at different temperatures were primarily caused by differences in triglyceride utilization efficiency by the moth, i.e., the triglyceride utilized for a given flight distance at suitable temperature was much less than at the unsuitable temperature, which might be one of the major reasons for difference in flight capacity of the moth at different flying temperature.

Key words: Spodoptera exigua, temperature, flight capacity, triglyceride