Evaluation Of Insecticides To Control HELIOTHIS SPP. ON COTTON IN MISSISSIPPI, 1976

Stoneville 213 cotton variety was planted on May 24'75 at the North Farm of the Mississippi Agricultural and Forestry Experiment Station. Eight-row plots, 75 ft long were arranged in a randomized complete block design replicated 4 times. Insecticides were applied to the center 4 rows of each plot at the rate of 3.8 gallons per acre, 4 mph, 40 psi, 3 nozzles per row. Applications for Heliothis spp. control were made 8 times between the dates of August 7 and September 13. Azinphosmemyl at 0.25 lb a.i./acre was applied 6 times during the study to control boll weevils. Plots were examined weekly for Heliothis spp. damaged squares by examining 100 squares per plot. After squaring ceased, 25 bolls per plot were examined for Heliothis spp. damage. Yields were estimated by counting the total number of open bolls on 6.5 linear ft of row at two locations within each plot.