European Corn Borer Control with Microbial and Pyrethroid Insecticides on Pre-Tassel Sweet Corn, 1993

Abstract

This test was conducted on the University of Minnesota, Rosemount Experiment Station in corn planted 1 Jun. Plots consisted of single rows on 30" centers, 30 ft in length, and separated by untreated border rows and 4 ft alleys between replicates. Treatments were arranged in a randomized complete block design with 4 replications. All plots were infested 27 Jul with approximately 25 neonate larvae/plant; larvae were applied to the whorl using ‘bazooka’ applicators. Plant growth stage at the time of infestation was primarily VI2-V13 and 95% pre-tassel (i.e., green tassel visible within the whorl). A single application of each treatment was made 4 Aug; the majority of larvae were second-instars. A medium-clearance Spirit sprayer was used to apply all materials. Liquid formulations were applied with one TX-10 nozzle/row at 40 psi, for a final spray volume of 30 gal/acre. Granular formulations were applied using a Gandy applicator. For all materials, applicator ground speed averaged 2 mph, wind speed 2 mph and ambient temperature 59°F. All treatments were evaluated 23 Aug by dissecting 5 plants per plot, from the tassel to the soil surface.