Establishment and maintenance of milkweed plants (Asclepias spp.) in agricultural landscapes of the North Central United States is needed to reverse the decline of North America's eastern monarch butterfly (Danaus plexippus) population. Due to lack of toxicity data it is unclear how insecticide use may reduce monarch productivity when milkweed habitat is placed near maize and soybean fields. To assess the potential effects of foliar insecticides, acute cuticular and dietary toxicity of five representative active ingredients were determined: beta-cyfluthrin (pyrethroid), chlorantraniliprole (anthranilic diamide), chlorpyrifos (organophosphate), and imidacloprid and thiamethoxam (neonicotinoids). Cuticular LD50 values for first instars ranged from 9.2 x 10-3 to 79 μg/g larvae for beta-cyfluthrin and chlorpyrifos, respectively. Dietary LC50 values for second instars ranged from 8.3 x 10-3 to 8.4 μg/g milkweed leaf for chlorantraniliprole and chlorpyrifos, respectively. To estimate larval mortality rates downwind from treated fields, modeled insecticide exposures to larvae and milkweed leaves were compared to dose-response curves obtained from bioassays with first-, second-, third-, and fifth-instar larvae. For aerial applications to manage soybean aphids, mortality rates at 60 m downwind were highest for beta-cyfluthrin and chlorantraniliprole following cuticular and dietary exposure, respectively, and lowest for thiamethoxam. To estimate landscape-scale risks, field-scale mortality rates must be considered in context of spatial and temporal patterns of insecticide use. This article is protected by copyright. All rights reserved.

中文翻译：

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评估叶面喷施杀虫剂对帝王蝶（Danaus plexippus）幼虫的田间风险。


需要在美国中北部的农业景观中种植和维护马利筋植物（Asclepias spp.），以扭转北美东部帝王蝶（Danaus plexippus）数量下降的趋势。由于缺乏毒性数据，尚不清楚当马利筋栖息地位于玉米和大豆田附近时，杀虫剂的使用如何会降低帝王蝶的生产力。为了评估叶面杀虫剂的潜在影响，测定了五种代表性活性成分的急性角质层和膳食毒性：高效氟氯氰菊酯（拟除虫菊酯类）、氯虫苯甲酰胺（邻氨基苯甲酰胺）、毒死蜱（有机磷）以及吡虫啉和噻虫嗪（新烟碱类杀虫剂）。 β-氟氯氰菊酯和毒死蜱对第一龄幼虫的表皮 LD50 值分别为 9.2 x 10-3 至 79 μg/g 幼虫。氯虫苯甲酰胺和毒死蜱在第二龄的膳食中的 LC50 值范围分别为 8.3 x 10-3 至 8.4 μg/g 马利筋叶。为了估计处理过的田地顺风处的幼虫死亡率，将幼虫和马利筋叶的杀虫剂暴露模型与从一龄、二龄、三龄和五龄幼虫生物测定中获得的剂量反应曲线进行了比较。对于空中施用防治大豆蚜虫而言，在表皮和饮食接触后，β-氟氯氰菊酯和氯虫苯甲酰胺分别在顺风 60 m 处的死亡率最高，而噻虫嗪最低。为了估计景观规模的风险，必须在杀虫剂使用的空间和时间模式的背景下考虑田间规模的死亡率。本文受版权保护。版权所有。