Source: University of Illinois

Farmers need to think twice when using soil insecticides this spring. The commercialization of corn hybrids with "built-in" resistance to certain insect pests has greatly contributed to the decline in use of soil insecticides.

Many insecticide choices are available to farmers, but several could restrict the use of certain corn herbicides. Specifically, using an organophosphate (OP) insecticide at planting or after corn emergence could restrict the use of herbicides that inhibit either the ALS or HPPD enzymes. The precautions and restrictions most often appear on the herbicide label and are due to the increased potential for corn injury following use of OP insecticides and ALS- or HPPD-inhibiting herbicides.
Original press release