What is the significance of the variant western corn rootworm in Iowa?
Undoubtedly producer concern over economic damage from the variant will increase with time. This will increase insecticide use or transgenic corn rootworm hybrids and a corresponding increase in production costs in rotated corn fields. However, the presence of the variant is not a harbinger of economic damage in a field. Only field scouting can reliably predict a problem. If sampling was not conducted in 2005, the only information that is available for 2006 planting decisions is whether or not corn lodged in 2005. If a grower has rotated corn that lodged and it was diagnosed as corn rootworm larval feeding, they may be justified in protecting their rotated corn in 2006. Additional information on the variant western corn rootworm may be found in the 2005 Integrated Crop Management Conference Proceedings, pages 85-91 or at online (online version requires Flash Player).
