Control of Aphids on Lettuce, 1996
Abstract ‘Red Fire’ leaf lettuce was planted at the Muck Crops Branch, Celeryville, OH, on 6 Aug. The field was fertilized with 800 lbs of 17-17-17 per acre. The experimental plots were three rows 20 inches apart, 30 ft long, with plant spacing at 12 inches within rows. Each treatment was replicated four times in a randomized complete block design. Pretreatment aphid counts were made 11 Sep by randomly selecting plants from the outside rows of each plot in replicates one and two and counting the number of aphids per plant. Pretreatment aphid counts averaged 32.2 aphids per plant. Treatment applications were made 11 and 19 Sep using a backpack sprayer delivering 50 gal/acre at 50 psi with a flat fan nozzle. Aphid populations were evaluated 17 and 26 Sep by randomly selecting five lettuce plants from the middle row of each plot and counting the density of aphids on each plant.