Department of Entomology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA.
Pest Manag Sci. 2013 Feb;69(2):285-91. doi: 10.1002/ps.3387. Epub 2012 Aug 30.
Neonicotinoid insecticides are generally efficacious against many turfgrass pests, including several important phloem-feeding insects. However, inconsistencies in control of western chinch bugs, Blissus occiduus, have been documented in field efficacy studies. This research investigated the efficacy of three neonicotinoid insecticides (clothianidin, imidacloprid and thiamethoxam) against B. occiduus in buffalograss under field conditions and detected statistically significant differences in B. occiduus numbers among treatments. A subsequent study documented the relative quantity and degradation rate of these insecticides in buffalograss systemic leaf tissues, using HPLC.
Neonicotinoid insecticides initially provided significant reductions in B. occiduus numbers, but mortality diminished over the course of the field studies. Furthermore, while all three neonicotinoids were present in the assayed buffalograss leaf tissues, imidacloprid concentrations were significantly higher than those of clothianidin and thiamethoxam. Over the course of the 28 day study, thiamethoxam concentrations declined 700-fold, whereas imidacloprid and clothianidin declined only 70-fold and 60-fold respectively.
Field studies continued to verify inconsistencies in B. occiduus control with neonicotinoid insecticides. This is the first study to document the relative concentrations of topically applied neonicotinoid insecticides in buffalograss systemic leaf tissues.
新烟碱类杀虫剂通常对许多草坪害虫有效，包括几种重要的韧皮部取食昆虫。然而，在田间药效研究中，已记录到西方盲蝽对新烟碱类杀虫剂的控制效果不一致。本研究在田间条件下调查了三种新烟碱类杀虫剂（噻虫嗪、吡虫啉和噻虫胺）对水牛草中西方盲蝽的防治效果，并检测到处理间西方盲蝽数量存在统计学差异。随后的一项研究使用 HPLC 法记录了这些杀虫剂在水牛草系统叶片组织中的相对数量和降解率。
新烟碱类杀虫剂最初显著降低了西方盲蝽的数量，但随着田间研究的进行，死亡率逐渐降低。此外，虽然三种新烟碱类杀虫剂都存在于检测的水牛草叶片组织中，但吡虫啉的浓度明显高于噻虫嗪和噻虫胺。在 28 天的研究过程中，噻虫嗪的浓度下降了 700 倍，而吡虫啉和噻虫嗪的浓度分别下降了 70 倍和 60 倍。
田间研究继续证实新烟碱类杀虫剂对西方盲蝽的控制效果不一致。这是首次记录在水牛草系统叶片组织中局部应用的新烟碱类杀虫剂的相对浓度。
