USDA-ARS Thad Cochran Southern Horticultural Laboratory, Poplarville, Mississippi, United States of America.
Department of Agriculture and Life Sciences, University of Maribor, Maribor, Slovenia.
PLoS One. 2023 May 3;18(5):e0285167. doi: 10.1371/journal.pone.0285167. eCollection 2023.
Pollinator health risks from long-lasting neonicotinoid insecticides like imidacloprid has primarily focused on commercially managed, cavity-nesting bees in the genera Apis, Bombus, and Osmia. We expand these assessments to include 12 species of native and non-native crop pollinators of differing levels of body size, sociality, and floral specialization. Bees were collected throughout 2016 and 2017 from flowering blueberry, squash, pumpkin, sunflower and okra in south Mississippi, USA. Within 30-60 minutes of capture, bees were installed in bioassay cages made from transparent plastic cups and dark amber jars. Bees were fed via dental wicks saturated with 27% (1.25 M) sugar syrup containing a realistic range of sublethal concentrations of imidacloprid (0, 5, 20, or 100 ppb) that are often found in nectar. Bees displayed no visible tremors or convulsions except for a small sweat bee, Halictus ligatus, and only at 100ppb syrup. Imidacloprid shortened the captive longevities of the solitary bees. Tolerant bee species lived ~10 to 12 days in the bioassays and included two social and one solitary species: Halictus ligatus, Apis mellifera and Ptilothrix bombiformis (rose mallow bees), respectively. No other bee species tolerated imidacloprid as well as honey bees did, which exhibited no appreciable mortality and only modest paralysis across concentration. In contrast, native bees either lived shorter lives, experienced longer paralysis, or endured both. Overall, longevity decreased with concentration linearly for social bees and non-linearly for solitary species. The percentage of a bee's captive lifespan spent paralyzed increased logarithmically with concentration for all species, although bumble bees suffered longest. Of greatest concern was comparable debilitation of agriculturally valuable solitary bees at both low and high sublethal rates of imidacloprid.
传粉媒介健康风险来自于像吡虫啉这样的长效新烟碱类杀虫剂，主要集中在商业管理的、具有洞穴状巢穴的蜜蜂属 Apis、熊蜂属 Bombus 和壁蜂属 Osmia 中。我们将这些评估扩展到包括 12 种具有不同体型大小、社会性和花卉特化程度的本地和非本地作物传粉媒介。2016 年和 2017 年，我们在美国密西西比州南部的开花蓝莓、南瓜、南瓜、向日葵和秋葵中采集了蜜蜂。在捕获后的 30-60 分钟内，蜜蜂被安装在由透明塑料杯和深琥珀色罐子制成的生物测定笼中。通过牙拭子将蜜蜂喂食饱和的 27%（1.25 M）糖水，其中含有一系列现实的亚致死浓度的吡虫啉（0、5、20 或 100 ppb），这些浓度通常存在于花蜜中。除了一种小型的熊蜂 Halictus ligatus 外，其他蜜蜂都没有出现明显的震颤或抽搐，而只有在 100 ppb 糖浆中才会出现这种情况。吡虫啉缩短了独居蜜蜂的人工饲养寿命。在生物测定中，耐吡虫啉的蜜蜂物种的寿命约为 10 到 12 天，包括两种社会性和一种独居性物种：Halictus ligatus、Apis mellifera 和 Ptilothrix bombiformis（玫瑰锦葵蜜蜂）。没有其他蜜蜂物种像蜜蜂那样耐受吡虫啉，蜜蜂在整个浓度范围内没有明显的死亡率，只有轻微的麻痹。相比之下，本地蜜蜂要么寿命更短，要么麻痹时间更长，要么两者都有。总的来说，对于社会性蜜蜂来说，寿命与浓度呈线性下降，而对于独居物种来说，寿命与浓度呈非线性下降。所有物种的寿命与浓度呈对数关系，而受影响的比例与浓度呈对数关系，尽管大黄蜂受影响的时间最长。最令人担忧的是，在低和高亚致死率的吡虫啉下，农业上有价值的独居蜜蜂都受到了类似的削弱。
