Department of Entomology, University of Nebraska-Lincoln, 202 Entomology Hall, Lincoln, NE 68583, USA.
J Econ Entomol. 2011 Feb;104(1):205-10. doi: 10.1603/ec10268.
The western chinch bug, Blissus occiduus Barber (Hemiptera: Blissidae), has emerged as a serious pest of buffalograss, Buchlod dactyloides (Nuttall) Engelmann. In general, neonicotinoid insecticides effectively control a variety of turfgrass insects, particularly phloem-feeding pests. However, because of well documented inconsistencies in control, these compounds are generally not recommended for chinch bugs. This study was designed to document the contact and systemic toxicity of three neonicotinoid insecticides (clothianidin, imidacloprid, and thiamethoxam) to B. occiduus. In contact bioassays, thiamethoxam was approximately 20-fold less toxic than clothianidin or imidacloprid to B. occiduus nymphs and three-fold more toxic to adults. In adult systemic bioassays, thiamethoxam was up to five-fold more toxic than clothianidin or imidacloprid. Interestingly, thiamethoxam was significantly more toxic to adults than to nymphs in both contact and systemic bioassays. This was not observed with clothianidin or imidacloprid. Bifenthrin, used for comparative purposes, exhibited 1844-fold and 122-fold increase in toxicity to nymphs and adults, respectively. These results provide the first documentation of the relative toxicity of these neonicotinoid insecticides to B. occiduus.
西方臀纹粉盲蝽， Blissus occiduus Barber（半翅目：盲蝽科），已成为野牛草， Buchlod dactyloides（Nuttall）Engelmann 的严重害虫。一般来说，新烟碱类杀虫剂能有效地控制各种草坪昆虫，尤其是韧皮部取食的害虫。然而，由于有大量文献记载控制效果不一致，这些化合物一般不推荐用于防治臀纹粉盲蝽。本研究旨在记录三种新烟碱类杀虫剂（噻虫嗪、吡虫啉和噻虫胺）对西方臀纹粉盲蝽的接触毒性和系统毒性。在接触生物测定中，噻虫胺对西方臀纹粉盲蝽若虫的毒性约比噻虫嗪或吡虫啉低 20 倍，对成虫的毒性低 3 倍。在成虫系统生物测定中，噻虫胺对成虫的毒性比噻虫嗪或吡虫啉高 5 倍。有趣的是，噻虫胺在接触和系统生物测定中对成虫的毒性均明显高于若虫，而噻虫嗪或吡虫啉则不然。双丙环虫酯用于比较，对若虫和成虫的毒性分别增加了 1844 倍和 122 倍。这些结果首次提供了这些新烟碱类杀虫剂对西方臀纹粉盲蝽相对毒性的资料。
