Efficacy of Insecticides for Control of Aphids in Cotton, 1986

Abstract

Abstract Stoneville 112 cotton was planted 6 May at the Macon Ridge Branch of the Northeast Research Station. Treatments were applied to plots that were 6 rows (40 inches wide) × 65 ft. The experimental design was a randomized complete block with 4 replications. Insecticides were applied with a high clearance sprayer equipped with a compressed air system for spraying small plots, delivering 2.5 gal/acre with 2 X-3 hollow cone nozzles/row. Applications were made on 21 Jul. Insecticides were evaluated 3 and 7 days after treatment by randomly collecting 5 leaves from the upper third of plants in the center 2 rows of all plots. Leaves were placed in 1 qt mason jars and transferred to the lab for processing. A solution of water, soap, and bleach was added to the jars, and the samples in individual jars were washed through a series of mesh sieves (#100 and #40) in order to separate the aphids from leaf samples. The contents collected on the #100 mesh sieve were washed into a Buchner funnel and separated onto filter paper for observation under the microscope.