Thiamethoxam

Thiamethoxam is a neonicotinoid insecticide and a precursor to the neonicotinoid insecticide clothianidin.^1,2 It binds to nicotinic acetylcholine receptors with low affinity (nAChRs; IC₅₀ = 5,000 nM for housefly head membranes) and does not activate non-desensitizing nAChRs in cockroach neurons in vitro (IC₅₀ = >3,000 nM).² Thiamethoxam induces mortality in a variety of insects, including A. craccivora, M. persicae, N. lugens, and S. littoralis when administered in contact/feeding assays (LC₈₀s = 12, 3, 0.8, and 3 mg AI/L, respectively) and via systemic administration (LC₈₀s = 0.8, 0.2, 0.05, and 0.8 mg AI/L, respectively) as well as D. balteata in a contact/feeding assay (LC₅₀ = 0.8 mg AI/L).¹ Thiamethoxam also induces 100% mortality of second instar larvae of the fall armyworm S. frugiperda and the tobacco budworm H. virescens in leaf-dip bioassays when used at a concentration of 200 mg/L.² Formulations containing thiamethoxam have been used in the control of insects in agriculture.

1.Maienfisch, P., Huerlimann, H., Rindlisbacher, A., et al.The discovery of thiamethoxam: A second-generation neonicotinoidPest. Manag. Sci.57(2)165-176(2001) 2.Nauen, R., Ebbinghaus-Kintscher, U., Salgado, V.L., et al.Thiamethoxam is a neonicotinoid precursor converted to clothianidin in insects and plantsPest. Biochem. Phys.76(2)55-69(2003)