Toxicity of Mk-244 to Tobacco Budworms on Cotton, 1997

Cotton was planted on 13 May at the Macon Ridge location of the Northeast Research Station into a Gigger Gilbert silt loam. Plots consisted of 4 rows (40 inch centers) X 50 ft. Treatments were arranged in a RCB and all treatments were replicated 5 times. Insecticides were applied on 14 Aug with a John Deere high-clearance sprayer and CO2-charged system calibrated to deliver 6 gpa through TX-8 hollow-cone nozzles (2/row) at 47 psi. The terminal leaf was removed from 5 randomly selected plants in each plot 2 h af-ter treatment, placed in a plastic bag and transported to the laboratory. Leaves were placed into individual plastic dishes and 3 1-d-old TBW larvae (LI stage) were transferred onto each leaf. Larval mortality was recorded 72 h after treatment. Larvae were considered dead if they did not respond to prod-ding. Data were analyzed with ANOVA, and means were separated according to DMRT. No rainfall occurred during this test.