Second Generation European Corn Borer Control with Aerial Application of Insecticides, 1992

Insecticides were aerially applied to natural ECB populations in 2 fields near Indianola, IA, using an Ag-Cat airplane. Treatments were replicated 3 times in each field in a RCBD. All liquid formulations were applied in 1.0 gal of water per acre. Pretreatment counts of egg masses on 10 Aug indicated 11 egg masses per 100 plants in Field 1 and 19 egg masses per 100 plants in Field 2. Insecticides were applied on 16-17 Aug; the 2nd application for the split Penncap-M treatment was made on 31 Aug. Treatments were evaluated on 24-25 Sep by splitting stalks, ear shanks, and removing the husks from 10 plants in the center row of each plot (center of the spray swath) and counting live larvae. Yields were taken from the center 4 rows (Field 1) or 6 rows (Field 2) of each plot with a combine. Yields were measured on a truck scale (Field 1) or with a weigh wagon (Field 2) and samples were adjusted to 15.5% moisture and number 2 corn. Yield plot sizes ranged from 0.35-0.64 acre (Field 1) and 0.4 acre (Field 2). Yield data were not collected from replication 2 in Field 2 because of a hybrid change that split the plots. Data were analyzed by using PROC ANOVA or PROC GLM procedures of SAS. Mean separation was accomplished using Fisher’s protected LSD procedure (P = 0.10).