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Thrips, especially tobacco thrips, are the most prevalent seedling pest of cotton in the Mid-Southern U.S. Commonly used methods for controlling tobacco thrips in cotton include insecticidal seed treatments, at-planting in-furrow insecticide applications, and supplemental foliar insecticide applications. However, field-evolved resistance has been documented to neonicotinoid insecticides, which are primarily applied as seed treatments. Pyrethroid insecticides also provide poor control of tobacco thrips across much of the Mid-Southern U.S., due to widespread resistance. Recent field and lab experiments have shown a decrease in the efficacy of organophosphate insecticides, primarily acephate, which typically are applied as a foliar treatment to manage tobacco thrips. To evaluate the current performance of at-planting insecticide treatments, studies were conducted at 13 locations across the Mid-Southern U.S. from 2014 to 2023. Statistically significant declines in percent control over time were observed for select insecticide treatments at specific growth stages throughout the duration of the study. Additionally, significant increases in temporal trends of qualitative injury ratings were observed throughout the course of the study for multiple insecticide treatments.
