Use of pesticides in agroecosystems is considered a major cause of bees diversity losses in the Neotropics, where Plebeia emerina (Friese) and Tetragonisca fiebrigi (Schwarz) (Hymenoptera: Apidae: Meliponini) are wild pollinators of native and crop plants. The aim of this study was to know the acute lethal toxicity of acetamiprid, malathion, phosmet and spinosad insecticides on P. emerina and T. fiebrigi. We obtained the mean concentration and mean lethal dose (LC50 and LD50) and the mean survival of workers after oral and topical exposure to insecticides, respectively. The LC50 values (ng a.i./μl of diet) and the decreasing order of toxicity for P. emerina was spinosad (4.96) > malathion (18.75) > phosmet (97.33) > acetamiprid (4204.06), and for T. fiebrigi also was spinosad (5.65) > malathion (8.39) > phosmet (53.91) > acetamiprid (9841.32), when orally exposed. The LD50 values (ng a.i./bee) and the decreasing order of toxicity for P. emerina was spinosad (1.90) > malathion (10.90) > phosmet (19.54) > acetamiprid (6216.55) and for T. fiebrigi was malathion (29.29) ≥ spinosad (29.79) > phosmet (41.95) > acetamiprid (1421.23), when topically exposed. The mean survival (hours) of contaminated bees by malathion, phosmet, and spinosad, was 11.81, 7.20, and 12.32 for P. emerina and 8.55, 7.20, and 13.34 for T. fiebrigi when orally exposed; and was 4.87, 9.87 and 11.17 for P. emerina, and 4.87, 4.76, and 19.05 for T. fiebrigi when topically exposed. Malathion, phosmet, and spinosad were highly toxic, while acetamiprid was moderately toxic. Our results indicated that the insecticides tested, mainly malathion, phosmet, and spinosad may be harmful to P. emerina and T. fiebrigi, making it essential to propose measures to minimize their impact on wild pollinators.

中文翻译：

---

杀虫剂对新热带无刺蜜蜂Plebeia emerina（弗里斯）和Tetragonisca fiebrigi（Schwarz）（膜翅目：Apidae：Meliponini）的毒性。

在新热带地区，农药在农业生态系统中的使用被认为是造成蜜蜂多样性丧失的主要原因，在那儿，Plebeia emerina（Friese）和Tetragonisca fiebrigi（Schwarz）（膜翅目：Apidae：Meliponini）是本地和农作物的野生传粉媒介。这项研究的目的是了解乙酰胺，马拉硫磷，磷光体和多杀菌素杀虫剂对埃默里纳海藻和费氏百日咳杆菌的急性致死毒性。我们分别获得了口服和局部接触杀虫剂后的平均浓度和平均致死剂量（LC50和LD50）以及工人的平均存活率。LC50值（ng ai /μl日粮）和绿脓杆菌的毒性递减顺序为多杀菌素（4.96）>马拉硫磷（18.75）>磷酸二甲酯（97.33）>乙酰胺（4204.06），而费氏纤毛虫也属于多杀菌素（5.65）>马拉硫磷（8.39）>磷酸（53.91）> 口服时对乙酰胺（9841.32）。绿脓杆菌的LD50值（ng ai / bee）和毒性的降序为多杀菌素（1.90）>马拉硫磷（10.90）>磷酸酯（19.54）>扑热息痛（6216.55），而费氏纤毛虫的马拉硫磷（29.29）≥局部暴露时，多杀菌素（29.79）>磷酸（41.95）>扑热息痛（1421.23）。马拉硫磷，磷酸酯和多杀菌素污染的蜜蜂的平均存活时间（小时）为：P。emerina分别为11.81、7.20和12.32，T.fiebrigi分别为8.55、7.20和13.34。当暴露在外时，P。emerina为4.87、9.87和11.17，T.fiebrigi为4.87、4.76和19.05。马拉硫磷，六聚氰胺和多杀菌素具有高毒性，而乙酰胺类则具有中等毒性。我们的结果表明，所测试的杀虫剂（主要是马拉硫磷，六磷酸和多杀菌素）可能对磷有害。