Control of Heliothis Spp. and Boll Weevils in Cotton, 1984

Abstract

Abstract Two full-season studies were conducted at the Red River Research Station, Bossier City, LA, to determine the efficacy of various commercial and experimental insecticides in controlling Heliothis spp, and boll weevils on cotton. Plots in the first study were 8 rows x 64.0 m (1.02-m centers) replicated 4 times. Plots in the second test were 4 rows X 30.5 m (1.02-m centers) replicated 4 times. Insecticides were applied with a high-clearance sprayer equipped with a CO2 system for spraying small plots. Insecticides were applied in 11.4 liters of water/acre with TX-3 hollow-cone nozzles spaced 50.8 cm apart. Treatments in the first study were applied on 10, 16, 24, 30 Jul, 6, 13, 21 and 27 Aug. In the second study, insecticide applications were made on 16, 24, 31 Jul, 7, 14, 22 and 27 Aug. All plots in the first and second study were oversprayed with Orthene 75S (0.25 lb (AI)/acre) on 25 and 22 Jun, respectively. On 6 Aug, both tests were sprayed with Kelthane MF (1.0 lb (AI)/acre) plus Triton CS-7 (1 qt/100 gal) for spider mite control. Insect populations and plant damage were monitored 2-3 days following each insecticide application by examining 25 terminals and 25 squares/plot. Terminal counts (eggs and live larvae) were not made following the last application date in each study. Data presented represents seasonal means. Yields were determined by mechanical harvest of 4 rows/plot on 17 and 18 Oct in the first test and 2 rows/plot on 19 Oct in the second study.