Control of Stink Bugs and Lepidopterans on Georgia Soybeans, 1997

The efficacy of 5 selected insecticide treatments for control of velvetbean caterpillars, soybean loopers and stink bugs, was evaluated at the Coastal Plain Experiment Station’s Ponder Farm, Tifton, GA. The insecticides were foliar applied on 4 Jun on ‘DP105’ and ‘Boggs’ soybeans that were planted in early Jun. Individual plots were 4 rows wide X 50 ft long with alleys 6 ft wide on each end and 1 border row on each side, arranged in a RCBD. There were 4 replications, 2 per variety. Each spray concentrate was applied with a CO2-powered backpack sprayer with 4 TX-12 nozzles on a 6 ft boom (2 nozzles per row) at 40 psi that delivered 19.5 gal/acre. Each plot was sampled prior to treatment and on 3, 7, 14 and 21 DAT (days after treatment) by taking a 25-sweep sample (15 in diam net) from a single row, and comparing insect densities in the treated plots to those in untreated plots. Soybeans were in the R5 growth stage (pods filling with seeds) at the initiation of the test. On the last sample date, only Boggs was sampled due to the late development (leaves yellowing/falling off) in DP105. All plots were harvested at maturity with a small plot combine. Yields were expressed in bushels per acre adjusted to 13% moisture. The data were subjected to ANOVA and Duncan’s multiple range test (P = 0.05).