Feeding and Oviposition Behavior and Life Cycle Strategies of Diabrotica : An Evolutionary View with Implications for Pest Management 1

Among the species of the genus Diabrotica that occupy the United States, voltinism and adult collection sites are closely related to the presence of suitable larval hosts; thus, species in the fucata group are multivoltine polyphags and species in the virgifera group are univoltine oligophags (or monophags). The group-specific differences in voltinism are attributed directly to the seasonal availability of the host plant and only indirectly to the climate. In the virgifera group, univoltinism combined with a narrow larval host range and limited search capability suggest that oviposition behavior is the primary determinant of whether the newly hatched larvae reach a suitable host. Review of the biosystematic, archaeological, and historical records indicates that D. virgifera sensu lato and D. l. barberi Smith and Lawrence have become pests of corn by convergent evolutlon. This evolutionary view suggests new avenues of research that are discussed in the text