Institut de Recherche sur la Biologie de l'Insecte UMR 7261, CNRS-Université de Tours, 37200 Tours, France.
Institut de Recherche sur la Biologie de l'Insecte UMR 7261, CNRS-Université de Tours, 37200 Tours, France
J Exp Biol. 2018 Oct 17;221(Pt 20):jeb187518. doi: 10.1242/jeb.187518.
Glyphosate is the most widely used herbicide in the world. Over the past few years, the number of studies revealing deleterious effects of glyphosate on non-target species has been increasing. Here, we studied the impact of glyphosate at field-realistic doses on learning in mosquito larvae (). Larvae of live in small bodies of water and perform a stereotyped escape response when a moving object projects its shadow on the water surface. Repeated presentations of an innocuous visual stimulus induce a decrease in response due to habituation, a non-associative form of learning. In this study, different groups of larvae were reared in water containing different concentrations of glyphosate that are commonly found in the field (50 µg l, 100 µg l, 210 µg l and 2 mg l). Larvae reared in a glyphosate solution of 2 mg l (application dose) could complete their development. However, glyphosate at a concentration of 100 µg l impaired habituation. A dose-dependent deleterious effect on learning ability was observed. This protocol opens new avenues to further studies aimed at understanding how glyphosate affects non-target organisms, such as insects. Habituation in mosquito larvae could serve as a parameter for testing the impact of pollutants in the water.
草甘膦是世界上使用最广泛的除草剂。在过去的几年中，越来越多的研究揭示了草甘膦对非靶标物种的有害影响。在这里，我们研究了在田间实际剂量下草甘膦对蚊子幼虫（）学习能力的影响。 幼虫生活在小水体中，当移动物体将其阴影投射到水面上时，它们会表现出刻板的逃避反应。由于习惯化，即一种非联想形式的学习，无害视觉刺激的重复呈现会导致反应减少。在这项研究中，不同组的幼虫在含有不同浓度草甘膦的水中饲养，这些浓度在田间很常见（50μg l、100μg l、210μg l 和 2mg l）。在 2mg l 的草甘膦溶液（应用剂量）中饲养的幼虫能够完成发育。然而，浓度为 100μg l 的草甘膦会损害习惯化。观察到学习能力呈剂量依赖性的有害影响。该方案为进一步研究草甘膦如何影响非靶标生物（如昆虫）开辟了新途径。蚊子幼虫的习惯化可以作为测试水中污染物影响的参数。
