Gaire Sudip, Scharf Michael E, Gondhalekar Ameya D
Center for Urban and Industrial Pest Management, Department of Entomology, Purdue University, West Lafayette, IN 47907, USA.
Insects. 2020 Feb 19;11(2):133. doi: 10.3390/insects11020133.
Management of the common bed bug ( L.) necessitates the use of multiple control techniques. In addition to synthetic pesticides and mechanical interventions, plant-derived essential oils represent one of the control options. Mixtures of two or more essential oil components (monoterpenoids) exhibit synergistic toxicity effects against insects due to increased cuticular penetration. Monoterpenoids, such as carvacrol, eugenol and thymol, are neurologically active and inhibit the nerve firing activity of . However, the effects of mixtures of these monoterpenoids on their toxicity and neuroinhibitory potential against are not known. In this study, the toxicity levels of a tertiary mixture of carvacrol, eugenol and thymol (1:1:1 ratio) and a binary mixture of synthetic insecticides, bifenthrin and imidacloprid (1:1 ratio) were evaluated against through topical bioassays and electrophysiology experiments. Both a mixture of monoterpenoids and the mixture of synthetic insecticides exhibited synergistic effects in topical bioassays. In electrophysiology experiments, the monoterpenoid mixture led to greater neuroinhibitory effects, whereas a mixture of synthetic insecticides caused higher neuroexcitatory effects in comparison to single compounds. This study shows evidence for neurological mechanisms of synergistic interactions between monoterpenoids and provides information regarding the utilization of natural compound mixtures for management.
普通臭虫（床虱）的防治需要采用多种控制技术。除了合成农药和机械干预措施外，植物源精油也是防治选择之一。两种或更多种精油成分（单萜类化合物）的混合物由于角质层渗透性增强而对昆虫表现出协同毒性作用。香芹酚、丁香酚和百里香酚等单萜类化合物具有神经活性，可抑制[具体对象]的神经放电活动。然而，这些单萜类化合物混合物对臭虫的毒性及其神经抑制潜力的影响尚不清楚。在本研究中，通过局部生物测定和电生理实验评估了香芹酚、丁香酚和百里香酚的三元混合物（比例为1:1:1）以及合成杀虫剂联苯菊酯和吡虫啉的二元混合物（比例为1:1）对臭虫的毒性水平。单萜类化合物混合物和合成杀虫剂混合物在局部生物测定中均表现出协同效应。在电生理实验中，与单一化合物相比，单萜类化合物混合物产生了更大的神经抑制作用，而合成杀虫剂混合物则引起了更高的神经兴奋作用。本研究证明了单萜类化合物之间协同相互作用的神经学机制，并提供了有关利用天然化合物混合物进行臭虫防治的信息。
