Velvetbean Caterpillar and Soybean Looper Control in Georgia Soybeans, 1991

Abstract

Abstract Eleven insecticide treatments were evaluated to determine their efficacy in controlling VBC and SL in soybean. In Test 1, 5 insecticides were foliar-applied on 14 Aug on 'Davis' soybeans. The field was planted on 22 May in conventionally prepared seedbeds on 36 inch row spacings at the University of Georgia Coastal Plain Experiment Station Bowen Farm in Tift County, GA. Individual plots were 6 rows × 100 ft long with 6 ft alleys on each end and a border row on each side. The treatments were arranged in a randomized complete block design with 4 replications. Each spray concentrate was applied with a CO2-powered backpack sprayer with 4 TX-12 nozzles on a 6-ft boom (spraying 2 rows) at 40 psi that delivered 17.4 gal of formulation per acre. Each plot was sampled prior to treatment and 2, 5, 8, 14, and 21 DAT by taking a 25-sweep sample (15-inch diam net) from a single row. In Test 2, 6 insecticides were applied on 13 Sep on 'Braxton' soybeans that were planted on 1 Jun in conventional 36 inch rows at the Gibbs Farm in Tift County. Plots were 6 rows wide by 20 ft long with 6-ft alleys on each end and arranged in a randomized complete block design with 3 replications. The spray concentrates were applied at a rate of 17.4 gal/acre as described in Test 1. Each plot was sampled prior to treatment and 4, 7, and 14 DAT by taking a 20-sweep sample from a single row. The numbers of VBC, SL, stink bugs, and arthropod predators (spiders, nabids, and bigeyed bugs) were recorded and analyzed using an ANOVA and DMRT (P = 0.05).