Residual Control of Stink Bugs (Hemiptera: Pentatomidae) and Leaffooted Bug (Hemiptera: Coreidae) with Selected Insecticides in Cotton

The boll-feeding complex of phytophagous stink bugs (Pentatomidae), leaffooted bugs (Coreidae), and plant bugs (Miridae) is the number one insect pest group of cotton in the southeastern United States. We examined the residual control of two widely used classes of insecticides (pyrethroids and organophosphates) in controlling three important species, the brown stink bug, Euschistus servus (Say), the southern green stink bug, Nezara viridula (L.), and the eastern leaffooted bug, Leptoglossus phyllopus (L.). The organophosphate dicrotophos provided excellent control of E. servus, N. viridula, and L. phyllopus at <1 and 24 h after insecticide application, and fair-to-good control up to 48 h. The pyrethroid lambda-cyhalothrin provided limited immediate and residual control of E. servus but excellent control of N. viridula and L. phyllopus out to 7 d after insecticide application, with the pyrethroid deltamethrin performing similarly on N. viridula. Subtle declines in mortality from 2008 (97%) to 2021 (82%) were noted with exposures of E. servus to dicrotophos 24 h after application, but mortalities at longer exposures seemed comparable across the 13-year span. Mortality of E. servus exposed to residues of lambda-cyhalothrin remained minimal and unchanged from 2008 to 2021. Mortality of N. viridula to lambda-cyhalothrin remained extremely high (100%) at 7 d after spraying in 2008 but decreased to 40% in 2021. Because these observations suggest a reduction in susceptibility of stink bugs to lambda-cyhalothrin and dicrotophos, efforts to monitor insecticide resistance in stink bugs are essential.