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

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.