During the summer of 2011, the ISU Corn Entomology Lab visited several fields in Iowa in response to complaints for rootworm injury to Bt rootworm corn, and to follow-up on fields that were visited in 2010 in response to grower complaints. To date, resistance of western corn rootworm has been found only for Bt corn producing Cry3Bb1, which was originally released as YieldGard Rootworm and is now the rootworm trait found in VTTriple and VTTriple Pro. Cry3Bb1 also is present as a pyramid with Bt toxin Cry35/35Ab1 in SmartStax
