Chemigation Treatment of Dough-Stage Popcorn to Manage Second Generation European Corn Borer Larvae in South Dakota, 1995

An irrigated site near Lower Brule, in central SD, was chosen for our study. Pretreatment counts indicated a severe ECB infestation (60% of ear zones containing egg masses). Treatments were applied in 10-acre wedges in a pieshaped RCBD. Each wedge contained 4 replicates, and distance from outer field perimeter was used as the blocking criterion. Insecticides were applied on 17 Aug using an Agri-Inject injector unit (calibrated to dispense 14.3 oz of fluid/h) connected to a Zimmatic central pivot irrigation system which delivered 0.32 inches of water during the application. One month after treatment (16 Sep), 15 randomly selected plants per plot were split vertically and examined for tunneling injury (cavities) to the stalk or shank and presence of ECB larvae. All data were analyzed with SAS’s General Linear Models (GLM) procedure and means were compared using DMRT.