EVALUATION OF INSECTICIDES FOR CONTROL OF NYMPH AND ADULT SOUTHERN GREEN STINK BUGS, 2002

The efficacy of selected insecticides was evaluated against Southern green stink bug (SGSB) nymphs and adults on cotton bolls at the Macon Ridge location of the Northeast Research Station (Franklin Parish). Plots of cotton plants (growth stage of 3-4 main stem nodes above the uppermost white flower located on the first position of a fruiting branch) were 4 rows (40-inch) x 50 ft. Treatments were arranged in a RBD with four replications and applied on 16 Aug with a high-clearance sprayer calibrated to deliver 6 gpa through TX-8 hollow cone nozzles (2/row) at 40 psi. At 2-3 h after application, 20 bolls (uppermost, first position quartersize, one/plant) were collected in each plot. Each boll was placed in a 3 oz plastic specimen vial and transported to the laboratory. Ten vials were infested with one SGSB nymph (4-5th instar) and 10 vials were infested with one SGSB adult. Specimen vials were stored in the laboratory under ambient conditions (ca. 80°F). Percent mortality was determined at 24, 48, and 72 h after infestation (HAI). The criterion for mortality was the inability of the insect to assume an upright posture within 5 second after being dislodged from the vial. Data were analyzed with ANOVA and means separated according to DMRT. No rainfall occurred between insecticide application and removal of bolls from the field.