The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), has adapted to crop rotation as a control method in much of Illinois and Indiana. Rotation-resistant females lay eggs in fields that are in annual rotation with corn, namely soybean. The mechanism for this behavioral adaptation is likely to be related to heightened levels of flight and locomotory activity, increasing the odds that rotation-resistant females enter non-corn crops. A molecular marker is needed to clearly distinguish between rotation-resistant and susceptible individuals. Microarray analysis was used to compare the two behavioral types for differential gene expression. Candidates showing a large difference in expression between types at a stringent level of significance will be confirmed using quantitative real-time RT-PCR. Potential markers for the rotation-resistance trait will be discussed.