Delayed Effects of Two Benzoylphenylureas on Platynota stultana (Lepidoptera: Tortricidae) in the Laboratory

Abstract

Delayed effects of two benzoylphenylureas (BPU’s), alsystin and UC 62644 (2,6-difluoro- N -[[[4-[3-dichloro-5-trifluoromethyl-2-pyridinyloxy]-3,5-dichlorophenyl]amino] carbonyl]benzamide), on Platynota stultana Walsingham were studied with life tables. Treatments were made by mixing the chemical solutions into artificial diet (15, 11, 8, and 0 ppm for alsystin, and 0.2, 0.1, 0.05, and 0.0 ppm for UC 62644). These concentrations were below the LC10 for the first two instars of P. stultana . Alsystin considerably decreased larval and pupal survivorship, but did not affect adult survivorship, longevity, or fecundity. Doubling times were increased >2-fold with the 11- and 15-ppm treatments of alsystin. Larval and pupal survivorship was decreased by only 40% at the highest concentrations of UC 62644. However, adult survivorship, longevity, and fecundity were greatly decreased with UC 62644. Doubling time was close to 13-fold higher with the 0.1-ppm treatment of UC 62644 compared with controls and could not be estimated for the 0.2-ppm treatment due to lack of fertile eggs. The potential of the two BPU’s in pest control is discussed.