Toxicity by Glass-Vial Bioassay of Selected Pyrethroid and Organophosphate Insecticides to Adult Brown Stink Bugs (Hemiptera: Pentatomidae) from Central Texas

Brown stink bug, Euschistus servus (Say), has greatly increased in numbers in the Brazos Valley in Central Texas and in many other areas of the Cotton Belt, and has become a major pest of cotton, Gossypium hirsutum L., and other crops including pecans, Carya illinoensis (Wangenh.) K. Koch. Use of insecticides is among the most important of the limited control options available against this pest. Glass-vial bioassays were used to evaluate the toxicity of selected synthetic pyrethroid and organophosphate insecticides to adult brown stink bug captured in blacklight traps. A comparison was also made of toxicity of λ-cyhalothrin to brown stink bug collected directly from the field to those captured in blacklight traps. Lethal concentration value (LC50) (upper and lower 95% confidence limits) for dicrotophos for 24-hour response, 0.30 (0.24–0.37) µg per vial, was significantly less compared to acephate with an LC50 of 1.38 (1.01–1.81) µg per vial and chlorpyrifos with an LC50 of 5.00 (4.27–5.67) µg pe...