EVALUATION OF SOIL INSECTICIDES FOR CONTROL OF SEEDCORN MAGGOTS, 2002

Abstract

Seed treatments and planting-time insecticides were tested in a loam soil near Ames, IA for their ability to protect seeds/seedlings against Seedcorn maggot (SM) injury. The experimental design was a RCB with four replications. Treatments were applied to 20-ft length rows with 30-inch row spacing. To attract ovipositing flies, a meat-and-bone meal bait was applied to shallow furrows, hand-made with hoes. The bait was hand applied (ca.1/3 oz/row-ft) to the bottom of the open seed furrow on 23 Apr. Corn seeds were hand planted (8-inch seed spacing) directly into the bait on 30 Apr. Granular insecticide treatments were applied with modified Noble metering units mounted on a small-plot bicycle applicator. Capture 2EC and Regent 4SC liquid insecticides were applied with a small-plot bicycle applicator operated at 3 mph. A 250067 nozzle, turned almost parallel to the row, provided a spray covering the entire seed furrow; 25 psi delivered 4 gpa of finished spray. Seeds were covered with soil and the soil firmed by hand. On 21 May, stand counts were taken from 15 ft of row. Seeds/seedlings from two 1-m sections of row were inspected for SM feeding and rated on the following 1-4 damage scale: (1) seed/seedling undamaged, (2) seed/seedling damaged, but plant established, (3) seed/seedling damaged, plant showing some signs of stress, (4) seed/seedling damaged, no plant or questionable establishment.