Japanese Beetle: Bioassay to Evaluate Control of Selected Adultcides on Grape, 1981

Abstract

Abstract Three insecticide formulations were evaluated for field efficacy in an experimental vineyard of Delaware grapes at Wooster, OH. Rows were spaced 8 ft apart with 8 ft between vines in a row. A replicate consisted of 15 adjacent vines in a row. A single treatment was applied Jul 15. Penncap-M and Sevin 50 WP plus Target NL (Agway) were applied at 58 psi with a C0? constant pressure sprayer equipped with a TeeJet D3-25 core. These 2 compounds were applied at the rate of 50 gal water/acre. Sevin XLR was diluted with 11 parts of water and applied with the same sprayer and some tips at 38 psi at the rate of 5.5 gal water/acre. Three leaves were removed at random from the outside canopy for use in bioassay. Leaves were placed in labeled plastic bags and brought into the laboratory where they were placed in floral tubes in a 1-gal ice cream carton. Ten adult Japanese beetles, of an unknown age were placed in each carton. The carton was modified by placing a 16-mesh wire screen over the bottom and cheese cloth over the top. Each bioassay included 4 replicates. The insect holding room was maintained at 75 F with ca. 807, RH under a 16-hr photoperiod.