São Paulo State University, Institute of Bioscience, Rio Claro, Brazil; Federal University of São Carlos, Department of Environmental Sciences, Sorocaba, Brazil.
Federal University of São Carlos, Department of Biology, Sorocaba, Brazil.
Environ Pollut. 2024 Nov 1;360:124712. doi: 10.1016/j.envpol.2024.124712. Epub 2024 Aug 10.
The indiscriminate use of pesticides is one of the factors directly impacting bee populations. However, limited information is available on the pesticide effects on solitary bees, especially in Neotropical countries. In this scenario, this study evaluated the survival and histopathological effects caused by the neonicotinoid insecticide acetamiprid (7 ng/μL) and the fungicide azoxystrobin (10 ng/μL) in the midgut and parietal fat body of the solitary bee Centris analis. Female and male newly-emerged bees were orally exposed for 48 h to the pesticides, or alone or in combination, under laboratory conditions. The exposure to the insecticide reduced the survival of males, while the mixture reduced survival in both sexes. Acetamiprid promoted a reduction in the number of regenerative nests in the midgut, alterations of fat body cells by increasing carbohydrates in trophocytes, and reduction of oenocyte size, and increased the frequency of pericardial cells in the advanced activity stage. Both pesticides caused changes in HSP70 immunolabelling of midgut from males at the end of pesticide exposure. Comparatively, the effects on males were stronger than in females exposed to the same pesticides. Therefore, acetamiprid alone and in mixture with fungicide azoxystrobin can be harmful to males and females of Neotropical solitary bee C. analis showing lethal and sublethal effects at a concentration likely to be found in the environment.
杀虫剂的滥用是直接影响蜜蜂种群的因素之一。然而，关于杀虫剂对独居蜜蜂的影响的信息有限，特别是在新热带国家。在这种情况下，本研究评估了新烟碱类杀虫剂噻虫胺（7ng/μL）和杀菌剂唑菌胺酯（10ng/μL）对独居蜜蜂 Centris analis 中肠和体壁脂肪体的生存和组织病理学影响。新羽化的雌性和雄性蜜蜂在实验室条件下经口暴露于杀虫剂 48 小时，或单独或混合暴露。暴露于杀虫剂降低了雄性的存活率，而混合物降低了两性的存活率。噻虫胺导致中肠再生巢数量减少，营养细胞中碳水化合物增加导致体壁细胞发生变化，卵母细胞大小减小，并增加了处于高级活动阶段的心包膜细胞的频率。两种杀虫剂都导致暴露于杀虫剂末期雄性中肠 HSP70 免疫标记发生变化。相比之下，暴露于相同杀虫剂的雄性所受影响比雌性更强。因此，噻虫胺单独和与杀菌剂唑菌胺酯混合使用可能对新热带独居蜜蜂 C. analis 的雄性和雌性有害，在环境中可能存在的浓度下表现出致死和亚致死效应。
