Assessments from the U.S. Environmental Protection Agency suggest that some insecticides can be affected by usage restrictions or label vacatur in the future. An experiment was conducted in Stoneville, Sidon, and Glendora, MS during 2023 to determine the effects of excluding insecticide classes for the control of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), on DP 2131 B3TXF ThryvOn cotton and DP 1646 B2XF cotton. Treatments were replicated in both the ThryvOn and non-ThryvOn varieties and included a season-long untreated control, all classes available for use, all classes except neonicotinoids, all classes except pyrethroids, all classes except organophosphates, and all classes except sulfoximines. Plots were scouted weekly to monitor tarnished plant bug densities and applications were made to plots independently using the best available insecticide options when each treatment reached established plant bug thresholds. Results indicated no significant differences in yield among exclusion class treatments in either variety. Significant reductions in yield were observed in the untreated control plots compared to plots that received insecticide intervention in both the ThryvOn and non-ThryvOn technologies. However, there were no significant differences between the economic returns of the untreated control plots compared to the plots receiving insecticide intervention in the ThryvOn technology. This evidence suggests that if insecticide usage is restricted from a single class, comparable yields can be achieved. However, it should be noted that any loss or reduction in insecticide usage currently used for tarnished plant bug control would result in increased selection pressure on the remaining insecticides, ultimately increasing resistance to those classes that remain available.
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