Abstract
Dosage-mortality responses of adult Popillia japonica Newman from Rivervale (northern NJ) indicated dieldrin resistance and greater inherent tolerance to both chlorpyrifos, and bendiocarb (a carbamate insecticide showing potential for turfgrass insect control) when compared to a strain from Adelphia (central NJ). Tests using 3rd-stage grubs indicated that, when compared at the LD50, the Rivervale grubs were ca. 90X as resistant to dieldrin as those from Adelphia.