A variant of the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), that circumvents crop rotation by flying out of cornfields to lay eggs in fields planted to other crops is presenting new management challenges to producers in the eastern Corn Belt. The rotation-resistant variant was first noted in east central Illinois and quickly dispersed to northern Indiana, southern Michigan, and northwestern Ohio. The spread of this variant throughout this region seems to be a result of high-altitude daytime flight. In this study, measurements of beetle flight activity at 10 m above ground level and meteorological factors are analyzed to evaluate the influence of atmospheric conditions on high-elevation flight of western corn rootworm. Collections of beetles from 72 d in July and August 2000-2002 reveal two pronounced peaks in high-elevation western corn rootworm flight, the first between 0645 and 1100 hours and the second between 1700 and 2030 hours. Low temperatures, high wind speeds, and darkness were found to limit beetle flight activity; however, within the range of weather conditions conducive to aerial movement, the level of flight activity was not strictly related to the values of individual environmental factors. Instead, peaks in western corn rootworm flight activity at 10-m elevation corresponded to predictable transitions in atmospheric conditions above the fields.
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Insect Science