Control of Tobacco Aphids with Foliar Insecticides, 1997C

Abstract

Abstract The objective of this experiment was to evaluate the efficacy of foliar applications of Orthene 75 SP, CGA-215944, and CGA-215944 with Silwet L-77 against tobacco aphids in the field. Plots were established at the Central Crops Research Station, Clayton, NC, on 7 May in a field with a Norfolk loamy sand soil. Individual plots were 4 rows (1.14 m apart) wide by 22 plants (ca. 13.7 m) long and were arranged in a RCB design with 5 treatments (untreated check included) and 4 blocks. Tobacco was transplanted on 7 May with a 2-row transplanter. On 2 Jul, the entire test was sprayed with foliar treatments. Foliar treatments were applied using a 2-row, CO2-powered backpack sprayer. Materials were applied through a single nozzle (Spraying Systems D2-33) per row at a pressure of 60 psi and 12.5 gpa. At 5, 12, and 21 days after treatment, aphid abundance in all plots were rated on a 0-7 scale as given in the table. Using this aphid abundance data, the average aphid rating was calculated. Aphid ratings were subjected to ANOVA and WD, K = 100, was used to separate treatment means.