Abstract：
The stingless bee Melipona scutellaris performs buzz pollination, effectively pollinating several wild plants and crops with economic relevance. However, most research has focused on honeybees, leaving a significant gap in studies concerning native species, particularly regarding the impacts of pesticide combinations on these pollinators. Thus, this study aimed to evaluate the sublethal effects of imidacloprid (IMD), pyraclostrobin (PYR), and glyphosate (GLY) on the behavior and fat body cell morphology and physiology of M. scutellaris. Foragers were orally exposed to the different pesticides alone and in combination for 48 h. Bees fed with contaminated solution walked less, moved slower, presented morphological changes in the fat body, including vacuolization, altered cell shape and nuclei morphology, and exhibited a higher count of altered oenocytes and trophocytes. In all exposed groups, alone and in combination, the number of cells expressing caspase-3 increased, but the TLR4 number of cells expressing decreased compared to the control groups. The intensity of HSP70 immunolabeling increased compared to the control groups. However, the intensity of the immunolabeling of HSP90 decreased in the IMD, GLY, and I + G (IMD + GLY) groups but increased in I + P-exposed bees (IMD + PYR). Alternatively, exposure to PYR and P + G (PYR + GLY) did not affect the immunolabeling intensity. Our findings demonstrate the hazardous effects and environmental consequences of isolated and combined pesticides on a vital neotropical pollinator. Understanding how pesticides impact the fat body can provide crucial insights into the overall health and survival of native bee populations, which can help develop more environmentally friendly approaches to agricultural practices.
摘要：
无刺的蜜蜂Meliponascutellaris进行嗡嗡声授粉，有效地授粉几种具有经济相关性的野生植物和作物。然而,大多数研究都集中在蜜蜂上，在有关本地物种的研究中留下了巨大的空白，特别是关于农药组合对这些传粉媒介的影响。因此，本研究旨在评估吡虫啉（IMD）的亚致死作用，吡唑酮酯(PYR),和草甘膦（GLY）对黄藻的行为和脂肪体细胞形态和生理的影响。觅食者单独和联合口服暴露于不同的农药48小时。用污染溶液喂养的蜜蜂行走较少，移动速度较慢,呈现脂肪体的形态变化，包括空泡化,改变细胞形状和细胞核形态，并表现出更高的改变的卵母细胞和滋养细胞计数。在所有暴露的群体中，单独和组合，表达caspase-3的细胞数量增加，但与对照组相比，表达TLR4的细胞数量减少。与对照组相比,HSP70免疫标记的强度增加。然而,IMD中HSP90的免疫标记强度降低，GLY,和I+G(IMD+GLY)组，但在I+P暴露蜜蜂(IMD+PYR)中增加。或者，暴露于PYR和P+G(PYR+GLY)不影响免疫标记强度。我们的发现证明了分离和组合农药对重要的新热带传粉媒介的有害影响和环境后果。了解农药如何影响脂肪体可以为本地蜜蜂种群的整体健康和生存提供至关重要的见解，这可以帮助开发更环保的农业实践方法。
