Department of Landscape Ecology, Institute for Natural Resource Conservation, Kiel University, Kiel, Germany.
Geobotany, Spatial and Environmental Sciences, Trier University, Trier, Germany.
Plant Biol (Stuttg). 2023 Dec;25(7):1046-1057. doi: 10.1111/plb.13577. Epub 2023 Sep 13.
Macrocyclic lactone anthelmintics are widely used to control invertebrate pests in livestock, such as sheep. While anthelmintic effects on non-target animals, such as dung-dwelling insects, are well studied, effects on seed germination are largely unknown. Seeds can come into contact with anthelmintics either during passage through the gastro-intestinal tract of grazing animals or when anthelmintics are excreted with their dung into the environment, which may result in changed germination patterns. We used four commonly applied macrocyclic lactones to assess their effects on germination: moxidectin, ivermectin, abamectin and doramectin as pure substances; moxidectin and ivermectin also in formulated form. We tested these pharmaceuticals on 17 different temperate grassland species from five plant families. Seeds were exposed to three concentrations of macrocyclic lactones (0.1, 1.0 and 10.0 mg·l ) under controlled conditions, and germination was assessed over a 6-week period. From these data, we calculated germination percentage, mean germination time and germination synchrony. Most of the tested species were significantly affected in germination percentage and/or mean germination time by at least one of the tested pharmaceuticals, with formulated moxidectin having the largest impact. In general, the effects found were species- and pharmaceutical-specific. While formulated substances generally reduced germination percentage and increased mean germination time, pure substances increased germination percentage. Synchrony showed less clear patterns in all pharmaceuticals. Although effect size and sign varied between species, our study shows that non-target effects of macrocyclic lactones commonly occur in terrestrial plants. This may impede successful seed exchange between habitats via sheep, and even translate into profound changes to grazed ecosystems.
大环内酯类驱虫药被广泛用于控制家畜（如绵羊）体内的无脊椎害虫。虽然驱虫药对非靶标动物（如粪生昆虫）的作用已得到充分研究，但对种子发芽的影响在很大程度上仍是未知的。种子可能会在以下两种情况下接触到驱虫药：一是通过放牧动物的胃肠道，二是驱虫药随粪便一起排泄到环境中，这可能导致发芽模式发生变化。我们使用四种常用的大环内酯类驱虫药来评估它们对发芽的影响：莫昔克丁、伊维菌素、阿维菌素和多拉菌素，分别作为纯物质；莫昔克丁和伊维菌素也以配方形式使用。我们在五种植物科的 17 种不同温带草原物种上测试了这些药物。在受控条件下，种子暴露于三种大环内酯类驱虫药浓度（0.1、1.0 和 10.0 mg·l ）下，在 6 周的时间内评估发芽情况。根据这些数据，我们计算了发芽百分比、平均发芽时间和发芽同步性。在发芽百分比和/或平均发芽时间方面，至少有 1 种被测试的药物对所测试的大多数物种都有显著影响，其中配方莫昔克丁的影响最大。总体而言，发现的影响是物种特异性和药物特异性的。虽然配方物质通常会降低发芽百分比并增加平均发芽时间，但纯物质会增加发芽百分比。在所有药物中，同步性的模式都不太明显。虽然效应大小和符号因物种而异，但我们的研究表明，大环内酯类驱虫药对非靶标植物的非靶标效应普遍存在。这可能会阻碍通过绵羊进行的栖息地间成功的种子交换，甚至导致放牧生态系统发生深刻变化。
