Chemical Control of the Pale Western Cutworm Infesting Wheat in Alberta, Canada

Abstract

Eight insecticides, applied to field infestations of the pale western cutworm, Agrotis orthogonia Morrison (Lepidoptera: Noctuidae), in winter and spring wheat were compared with endrin. The insecticide CL-47031 [cyclic ethylene (dicthoxyphosphinyl) dithioimidocarbonate] at 6 oz per acre gave better control than endrin at 4 oz per acre. Bayer 25141 [O, O-diethyl O-p-(methylsulfinyl) phenyl phosphorothioate] exhibited some promise in one test but still ranked below endrin and CL-47031. Endosulfan, trichlorfon, azinphosmethyl, azinphosmethylazinphosethyl 1:1, CL-52160 (O, O, O', O'-tetramethyl O, O'-thiodi-p-phenylene phosphorothioate), CL-47470 [cyclic propylene (dimethoxyphosphinyl) dithioimidocarbonate J. and Zinophos® (O, O-diethyl O-2-pyrazinyl phosphorothioate) were less ctfective than endrin. CL-47031 and Bayer 25141 show promise as substitutes for cyclodicne compounds for the control of the pale western cutworm in the field.