Corn hybrids with corn rootworm traits help manage a serious problem, but research shows that traits alone may not be enough to protect corn yields, especially in regions with heavy pressure. As you harvest corn this fall, you will remember why you want to avoid lodging.
Current RW-trait corn is low-dose, which could result in noticeable feeding by larvae before they are controlled. This feeding leads to scarred roots, reduced standability and often, reduced yields. Other early-season pests, like wireworm, cutworm or white grub infestations are also not controlled by traited hybrids.
University of Illinois data from DeKalb and Urbana, where the rootworm pressure is historically heavy, shows that the combination of a soil-applied insecticide and most rootworm Bt corn hybrids (left) resulted in significantly lower node-injury ratings. Syngenta trials in 2007 and 2008 indicated a significant return on investment in over 70 percent of cases when insecticide was applied over traited corn in heavy rootworm pressure areas.