Corn Rootworm Resistance to Chlorinated Hydrocarbon Insecticides in Illinois

Abstract

During July, 1962, a field was located in central Illinois in which the northern corn rootworm, Diabrotica longicornis, had apparently developed resistance to soil treatments with chlorinated hydrocarbon insecticides. This field of continuous corn had been treated in 6 of the last 8 years with aldrin and had been irrigated in 3 of the last 9 years. Laboratory tests with adults from this field showed a high degree of resistance compared with beetles from an untreated field in east-central Illinois which had been in corn at least 7 years consecutively. Two nearby fields which had been treated the same way as the first field showed no indication of the development of resistance in the insect. These had not been irrigated.