Cotton Bollworm and Tobacco Budworm Control, 1978

Abstract

Abstract Eighty-four rows of Coker 310 were planted on April 17'78, on Norfolk sandy loam soil In Scotland County, North Carolina, at 12-13 lb per acre. Six rows of 35 ft were utilized per treatment in randomized complete block design with 4 repii-cates. Temik 15G was applied at planting at 0.45 lb ai/acre for early season insect control. Insecticide treatments were applied to the middle 4 rows by a 2-gal C02~powered backpack sprayer delivering 5 gpa at 60 psi and 1.5 mph with a single TX-4 hollow cone nozzle per row. Applications were made on Aug 4, 7, 10, 17, 18, 24, 31 and September 7 and 14. Weekly inspections of 50 fruiting forms for damage and live worms were made in each plot 72-96 hr post-treat-ment. The percent Heliothis zea vs. H. virescens was determined by examination of 50-100 larvae sampled from border rows on August 8, 10, 17, 24, 28, and September 7, 19 and 21. Yields were calculated by hand picking middle two rows on November 14 from each plot and converting to lb of lint per acre.