Aerial Insecticide Applications for Control of First-Generation European Corn Borer Larvae in South Dakota, 1994

A corn field near Beresford, SD, was chosen to evaluate aerially-applied chemical and biological insecticide treatments for control of first-generation ECB larvae. Pretreatment counts indicated a light, but uniform infestation of ECB larvae in 42% of plants sampled. Stadial composition consisted of 13, 32, 38, and 17% 1st-, 2nd-, 3rd-, and 4th-instar larvae, respectively. A strip-plot experimental design was used. Each strip contained 4 replicates. Individual treatment plots were 40 m (41 rows) by 122 m. Insecticides were applied on 29 Jun at whorl (ca. 10 d prior to tasseling) stage. All insecticide treatments were applied at 8.0 lb formulated product/acre in 20-m swaths using a Cessna Ag Truck aircraft. A Duke metering system mounted on the aircraft was used for insecticide calibration and application procedures. Approximately 1 month following treatment (28 Jul), 40 plants in each plot were randomly selected, split vertically and examined for cavity (tunnelling) damage. The number and length of cavities were recorded and analyzed using SAS’s General Linear Models (GLM) procedure with means being compared by DMRT.