Control of Tobacco Aphids with Foliar Insecticides, 1997A

The objective of this experiment was to evaluate the efficacy of foliar applications of Orthene 75 SP, Provado 1.6 FL, Orthene 97 PE, and Thiodan 3 EC against tobacco aphids in the field. Plots were established at the Central Crops Research Station, Clayton, NC, on 9 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 7 treatments (untreated check included) and 4 blocks. Tobacco was transplanted on 9 May with a 2-row transplanter. Soil moisture was good. Treatments were applied on 9 Jul. 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, 9, and 16 days after treatment, aphid abundance in all plots was 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.