Foliar Sprays to Control Insect Pests on Late-Planted Sweet Corn, 1986

Abstract

Abstract Silver Treat’ sweet corn were planted 10 Jul to a Sassafras sandy loam field. Plots were 4 rows wide on 30-inch centers and 25-ft long. Foliar sprays at silking were applied with 4 nozzles/row, directed at the ear zone, using a self-propelled, high-clearance sprayer calibrated to deliver 83 gal/acre at 40 psi operated at 2 mph. The center two rows of each plot were treated and the outer two rows were untreated guard rows. Sprays were applied on 26, 29 Aug; 3, 5, 8 and 12 Sep. At harvest (17 Sep), twenty ears from the center 2 rows of each plot were husked and evaluated for ‘worm’ damage as “fresh-market” (clean ears, no damage evident), “processing” (evidence of tip feeding, but less than 3.6 cm tip damage) and “culls” (tip damage beyond 3.6 cm to the side and/or bottom). All ‘worms’ found within the husk or ear were identified, counted and recorded; all ears were then weighed and total weights recorded. On 28 Oct, twenty stalks from the center two rows of each plot were split from three nodes above the ear to three nodes below the ear and each 2.5 cm of European corn borer (ECB) damage was recorded as one cavity.