Azpiazu C, Hinarejos S, Sancho G, Albacete S, Sgolastra F, Martins C A H, Domene X, Benrezkallah J, Rodrigo A, Arnan X, Bosch J
CREAF (Centre for Ecological Research and Forestry Applications), 08193 Bellaterra, Spain; Institut de Biologia Evolutiva (CSIC, Universitat Pompeu Fabra), 08034 Barcelona, Spain; Universidad Politécnica de Madrid, 28040 Madrid, Spain.
Sumitomo Chemical, Saint Didier au Mont d'Or, France.
Ecotoxicol Environ Saf. 2023 Oct 1;264:115398. doi: 10.1016/j.ecoenv.2023.115398. Epub 2023 Aug 25.
Pesticide exposure is an important driver of bee declines. Laboratory toxicity tests provide baseline information on the potential effects of pesticides on bees, but current risk assessment schemes rely on one species, the highly social honey bee, Apis mellifera, and there is uncertainty regarding the extent to which this species is a suitable surrogate for other pollinators. For this reason, Osmia cornuta and Osmia bicornis have been proposed as model solitary bee species in the EU risk assessment scheme. The use of solitary bees in risk assessment requires the development of new methodologies adjusted to the biology of these species. For example, oral dosing methods used with honey bees cannot be readily applied to solitary bees due to differences in feeding behaviour and social interactions. In this study, we describe the "petal method", a laboratory feeding method, and validate its use in acute and chronic exposure oral tests with Osmia spp. We conducted five experiments in which we compared the performance of several artificial flowers combining visual and olfactory cues against the petal method, or in which variations of the petal method were confronted. We then use the results of these experiments to optimize the feeding arenas and propose standardized methods for both acute and chronic exposure tests. The petal method provides high levels of feeding success, thus reducing the number of bees needed. It works with a wide variety of petal species and with both female and male Osmia spp., thus ensuring reproducibility across studies. To validate the use of the petal method in ecotoxicology tests, we assess the toxicity of a standard reference insecticide, dimethoate, in O. cornuta adults and determine LD50 values for this species. The petal method should facilitate the inclusion of solitary bees in risk assessment schemes therefore increasing the protection coverage of pesticide regulation.
接触农药是蜜蜂数量减少的一个重要驱动因素。实验室毒性测试提供了农药对蜜蜂潜在影响的基线信息，但目前的风险评估方案仅基于一个物种，即高度群居的蜜蜂——西方蜜蜂（Apis mellifera），而对于该物种在多大程度上可作为其他传粉者的合适替代物种仍存在不确定性。因此，角额壁蜂（Osmia cornuta）和双角壁蜂（Osmia bicornis）已被提议作为欧盟风险评估方案中的独居蜜蜂模型物种。在风险评估中使用独居蜜蜂需要开发适应这些物种生物学特性的新方法。例如，由于取食行为和社会互动的差异，用于蜜蜂的口服给药方法不能直接应用于独居蜜蜂。在本研究中，我们描述了一种实验室喂食方法——“花瓣法”，并验证了其在对壁蜂属（Osmia spp.）进行急性和慢性暴露口服试验中的应用。我们进行了五项实验，在这些实验中，我们将几种结合视觉和嗅觉线索的人造花的性能与花瓣法进行比较，或者对比花瓣法的不同变体。然后，我们利用这些实验结果优化喂食场地，并为急性和慢性暴露试验提出标准化方法。花瓣法具有很高的喂食成功率，从而减少了所需蜜蜂的数量。它适用于多种花瓣种类以及雌性和雄性壁蜂属物种，从而确保了不同研究之间的可重复性。为了验证花瓣法在生态毒理学试验中的应用，我们评估了一种标准参考杀虫剂乐果对角额壁蜂成虫的毒性，并确定了该物种的半数致死剂量（LD50）值。花瓣法应有助于将独居蜜蜂纳入风险评估方案，从而扩大农药监管的保护范围。
