Bioassay Evaluation of Insecticides, 1988

Four insecticides were evaluated for efficacy against adult JB, TPB, MS, PB, and SSB. A 13-yr-old experimental blueberry planting at Wooster, Ohio, was used for this study. Plots consisted of 2 blueberry bushes, with 4 replications/treatment in a randomized complete block design. Treatments were applied as foliar sprays at a rate of 150 gal/acre (1,403 liter/ha) on 21 Jun, 29 Jun, 15 Jul, and 4 Aug, using a hand-held CO2 sprayer operating at 45 psi (3.2 kg/cm2) and equipped with a 9505-E-TeeJet nozzle. At the appropriate number of days after insecticides were applied, 5 leaves and 5 berries were removed at random from each replicate and placed in a ventilated 1-gal round ice cream container. Bioassays were begun after treated foliage had dried and samples could be taken. Ten adults of each available species were added to containers, and the number of dead insects was recorded 24 h later.