Parkinson Rachel H, Fecher Caroline, Gray John R
Grass Laboratory, Marine Biological Laboratory, Woods Hole, MA, United States.
Department of Zoology, University of Oxford, Oxford, United Kingdom.
Front Insect Sci. 2022 Aug 17;2:936826. doi: 10.3389/finsc.2022.936826. eCollection 2022.
Honeybees use wide-field visual motion information to calculate the distance they have flown from the hive, and this information is communicated to conspecifics during the waggle dance. Seed treatment insecticides, including neonicotinoids and novel insecticides like sulfoxaflor, display detrimental effects on wild and managed bees, even when present at sublethal quantities. These effects include deficits in flight navigation and homing ability, and decreased survival of exposed worker bees. Neonicotinoid insecticides disrupt visual motion detection in the locust, resulting in impaired escape behaviors, but it had not previously been shown whether seed treatment insecticides disrupt wide-field motion detection in the honeybee. Here, we show that sublethal exposure to two commonly used insecticides, imidacloprid (a neonicotinoid) and sulfoxaflor, results in impaired optomotor behavior in the honeybee. This behavioral effect correlates with altered stress and detoxification gene expression in the brain. Exposure to sulfoxaflor led to sparse increases in neuronal apoptosis, localized primarily in the optic lobes, however there was no effect of imidacloprid. We propose that exposure to cholinergic insecticides disrupts the honeybee's ability to accurately encode wide-field visual motion, resulting in impaired optomotor behaviors. These findings provide a novel explanation for previously described effects of neonicotinoid insecticides on navigation and link these effects to sulfoxaflor for which there is a gap in scientific knowledge.
蜜蜂利用广域视觉运动信息来计算它们从蜂巢飞行的距离，并且这些信息在摇摆舞期间会传达给同种个体。种子处理杀虫剂，包括新烟碱类和诸如氟啶虫胺腈等新型杀虫剂，即使以亚致死量存在，也会对野生蜜蜂和养殖蜜蜂产生有害影响。这些影响包括飞行导航和归巢能力的缺陷，以及暴露的工蜂存活率降低。新烟碱类杀虫剂会干扰蝗虫的视觉运动检测，导致逃避行为受损，但此前尚未表明种子处理杀虫剂是否会干扰蜜蜂的广域运动检测。在这里，我们表明，亚致死剂量暴露于两种常用杀虫剂，吡虫啉（一种新烟碱类）和氟啶虫胺腈，会导致蜜蜂的视动行为受损。这种行为效应与大脑中应激和解毒基因表达的改变相关。暴露于氟啶虫胺腈会导致神经元凋亡稀疏增加，主要集中在视叶，然而吡虫啉没有这种影响。我们认为，暴露于胆碱能杀虫剂会破坏蜜蜂准确编码广域视觉运动的能力，导致视动行为受损。这些发现为先前描述的新烟碱类杀虫剂对导航的影响提供了一种新的解释，并将这些影响与氟啶虫胺腈联系起来，而对于氟啶虫胺腈，科学知识存在空白。
