Krishnan Niranjana, Zhang Yang, Aust Melanie E, Hellmich Richard L, Coats Joel R, Bradbury Steven P
Toxicology Program and Department of Entomology, Iowa State University, Ames, Iowa, USA.
Beijing Great-Agri Institute of Pesticide Technology, Beijing, China.
Environ Toxicol Chem. 2021 Jun;40(6):1761-1777. doi: 10.1002/etc.5016. Epub 2021 May 5.
Conservation of North America's eastern monarch butterfly (Danaus plexippus) population would require establishment of milkweed (Asclepias spp.) and nectar plants in the agricultural landscapes of the north central United States. A variety of seed-treatment and foliar insecticides are used to manage early- and late-season pests in these landscapes. Thus, there is a need to assess risks of these insecticides to monarch butterfly life stages to inform habitat conservation practices. Chronic and acute dietary toxicity studies were undertaken with larvae and adults, and acute topical bioassays were conducted with eggs, pupae, and adults using 6 representative insecticides: beta-cyfluthrin (pyrethroid), chlorantraniliprole (anthranilic diamide), chlorpyrifos (organophosphate), imidacloprid, clothianidin, and thiamethoxam (neonicotinoids). Chronic dietary median lethal concentration values for monarch larvae ranged from 1.6 × 10 (chlorantraniliprole) to 5.3 (chlorpyrifos) μg/g milkweed leaf, with the neonicotinoids producing high rates of arrested pupal ecdysis. Chlorantraniliprole and beta-cyfluthrin were generally the most toxic insecticides to all life stages, and thiamethoxam and chlorpyrifos were generally the least toxic. The toxicity results were compared to insecticide exposure estimates derived from a spray drift model and/or milkweed residue data reported in the literature. Aerial applications of foliar insecticides are expected to cause high downwind mortality in larvae and eggs, with lower mortality predicted for adults and pupae. Neonicotinoid seed treatments are expected to cause little to no downslope mortality and/or sublethal effects in larvae and adults. Given the vagile behavior of nonmigratory monarchs, considering these results within a landscape-scale context suggests that adult recruitment will not be negatively impacted if new habitat is established in close proximity of maize and soybean fields in the agricultural landscapes of the north central United States. Environ Toxicol Chem 2021;40:1761-1777. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
保护北美洲东部黑脉金斑蝶（Danaus plexippus）种群需要在美国中北部的农业景观中种植马利筋（Asclepias spp.）和花蜜植物。人们使用多种种子处理剂和叶面杀虫剂来防治这些景观中早季和晚季的害虫。因此，有必要评估这些杀虫剂对黑脉金斑蝶各生命阶段的风险，以为栖息地保护措施提供依据。我们对幼虫和成虫进行了慢性和急性经口毒性研究，并使用6种代表性杀虫剂对卵、蛹和成虫进行了急性体表生物测定：高效氯氟氰菊酯（拟除虫菊酯类）、氯虫苯甲酰胺（邻氨基苯甲酰胺类）、毒死蜱（有机磷类）、吡虫啉、噻虫胺和噻虫嗪（新烟碱类）。黑脉金斑蝶幼虫的慢性经口半数致死浓度值范围为1.6×10（氯虫苯甲酰胺）至5.3（毒死蜱）μg/g马利筋叶片，新烟碱类导致蛹期蜕皮受阻的比例较高。氯虫苯甲酰胺和高效氯氟氰菊酯通常对所有生命阶段毒性最大，噻虫嗪和毒死蜱通常毒性最小。我们将毒性结果与通过喷雾漂移模型得出的杀虫剂暴露估计值和/或文献中报道的马利筋残留数据进行了比较。预计叶面杀虫剂的空中喷洒会导致幼虫和卵在下风向的高死亡率，而成虫和蛹的死亡率预计较低。预计新烟碱类种子处理剂对幼虫和成虫几乎不会造成下风向死亡率和/或亚致死效应。鉴于非迁徙黑脉金斑蝶的易动行为，在景观尺度背景下考虑这些结果表明，如果在美国中北部农业景观中靠近玉米和大豆田的地方建立新的栖息地，成虫补充不会受到负面影响。《环境毒理学与化学》2叭21年；40：1761 - 1777。©2021作者。《环境毒理学与化学》由Wiley Periodicals LLC代表SETAC出版。
