“A significant consequence of the seed mixture infrastructure emerging within the corn insect protection arena is increasing pressure on the long-term sustainability of the soil insecticide market,” Gray said. “As the number of refuges configured as blocks, strips, or separate fields declines, soil insecticide use should also be reduced. Ultimately, loss of soil insecticide products will result in reduced flexibility of producers to effectively manage economic infestations of white grubs, wireworms, and other soil insects.”

In addition, if resistance develops to Bt hybrids and becomes widespread, growers will need to have some remaining tools to manage insect pests of corn, Gray added.

“It remains to be seen whether some groups within the agribusiness sector will maintain their investments in this competitive arena just in case resistance develops or to offer products targeted against secondary soil insect pests,” Gray said.

Onstad’s research, “Seeds of change: Corn seed mixtures for resistance management and integrated pest management,” was published in the Journal of Economic Entomology. Collaborating researchers include P.D. Mitchell, T.M. Hurley, J.G. Lundgren, R.P. Porter, C.H. Krupke, J.L. Spencer, C.D. DiFonzo, T.S. Baute, R.L. Hellmich, L.L. Buschman, W.D. Hutchison and J.F. Tooker.