Resistance monitoring to four insecticides and mechanisms of resistance in Lygus lineolaris Palisot de Beauvois (Hemiptera: miridae) populations of southeastern USA cotton

Authors: DORMAN, SETH - Virginia Polytechnic Institution & State University; GROSS, AARON - Virginia-Maryland Regional College Of Veterinary Medicine (VMRCVM); MUSSER, FRED - Mississippi State University; CATCHOT, BEVERLY - Mississippi State University; SMITH, RONALD - Auburn University; REISIG, DOMINIC - North Carolina State University; REAY-JONES, FRANCIS - Clemson University; ROBERTS, PHILLIP - University Of Georgia; TAYLOR, SALLY - Virginia Polytechnic Institution & State University

Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/7/2020
Publication Date: 6/22/2020
Citation: Dorman, S.J., Gross, A.D., Musser, F.R., Catchot, B.D., Smith, R.H., Reisig, D.D., Reay-Jones, F.P., Roberts, P.M., Taylor, S.V. 2020. Resistance monitoring to four insecticides and mechanisms of resistance in Lygus lineolaris Palisot de Beauvois (Hemiptera: miridae) populations of southeastern USA cotton. Pest Management Science. 76(12):3935-3944. https://doi.org/10.1002/ps.5940.
DOI: https://doi.org/10.1002/ps.5940

Interpretive Summary: Damaging infestations of the tarnished plant bug, have become more frequent in populations along the east coast. Foliar insecticide use has increased dramatically in response. Data regarding the effectiveness of available insecticides are needed to evaluate tarnished plant bug susceptibility and resistance levels to commonly used and recommended insecticides for managing this pest in the southeastern USA. Elevated resistance levels to two commonly used insecticides, acephate and bifenthrin, were measured in tarnished plant bug populations collected from wildand cultivated hosts in Virginia, North Carolina and northern Alabama when compared to a susceptible laboratory population. High levels of bifenthrin resistance were observed in 2018 and 2019. Results suggest that insecticide resistance is present in some locations.Results can serve as a baseline for continued monitoring of tarnished plant bug insecticide resistance and inform insecticide resistance management strategies that help southeastern USA cotton producers to minimize inputs and slow resistance development.

Technical Abstract: Economically damaging infestations of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), have become more frequent in Virginia and North Carolina cotton since 2013 and 2010, respectively. Foliar insecticide use has increased dramatically in response. Efficacy data (LC50) are needed to evaluate L.lineolaris susceptibility and resistance levels (RR50) to commonly used and recommended insecticides for managing this pest in the southeastern USA. Elevated resistance levels to acephate and bifenthrin were measured in L. lineolaris populations collected from wildand cultivated hosts in Virginia, North Carolina and northern Alabama when compared to a susceptible laboratory population. High levels of bifenthrin resistance were observed in 2018 and 2019. Mixed-function oxidase and esterase (EST)inhibitors,piperonyl butoxide and S,S,S-Tributyl phosphotrithioatin respectively, had a synergistic effect on bifenthrin with resistant populations of L. lineolaris. Bifenthrin-resistant L. lineolarispopulations expressed elevated levels of cytochrome P450(CYP450) monooxygenase and general EST activity. Results suggest that insecticide resistance is present in some locationsand that CYP450and EST activity in L.lineolariscontribute to pyrethroid resistance in the southeastern USA. Results can serve as a baseline for continued monitoring of L. lineolaris insecticide resistance and inform insecticide resistance management strategies that help southeastern USA cotton producers to minimize inputs and slow resistance development.