Reduction of Aphid Contamination on Sweet Corn Ears, 1992

Abstract

Abstract ‘Dazzel’ (sh2) sweet corn was planted 20 Jun in Tioga silt-loam soil at New Paltz, NY. Treatments were arranged in 2-row plots 149 m long, replicated 4 times in a randomized block design. Foliar spray treatments were applied to silking corn (27 Aug, 31 Aug and 4 Sep) using a high clearance sprayer driven at 2.12 km/hr equipped with three D2-25 cone nozzles/row, dispensing 450 liters/ha at 7.03 kg/cm2. On 9 Sep, 25 ears/replicate were randomly selected and given a rating based on the presence and location of aphid colonies (i.e. > 5 nymphs), where: 0 aphids = 0, aphids at the base of ear = 1, aphids at the side of ear or between husk layers = 2, aphids at the silk zone or on kernels = 3). The numerical ratings were additive if aphids were present at more than one location on the ear. The proportion of ears having a rating of 2 or less was used to determine percent marketability. The presence of aphids at the base is not in itself detrimental to marketability, but aphids located between the layers of husks or within the silks or kernels is cause for rejection.