Neonicotinoid insecticides are used to reduce crop damage caused by insect pests, but sublethal levels could affect development and reproduction in nontarget insects, such as monarch butterflies (Danaus plexippus) (Lepidoptera: Nymphalidae). To investigate the impact of field-realistic concentrations of the neonicotinoid clothianidin on monarch butterflies, we grew swamp milkweed (Asclepias incarnata) (Apocynaceae) in either low (15 ng/g of soil) or high (25 ng/g of soil) levels of clothianidin, or in a control (0 ng/g), then raised monarchs on the milkweed. Morphological traits of monarch caterpillars were measured during development and, once they eclosed, were mated as adults to quantify egg size and mass and the number of eggs laid. Although the effects of the treatment had complex effects on caterpillar length, width and volume of late-instar caterpillars were negatively affected. Fifth-instar caterpillars from the high-dose insecticide treatment had lower mass than other groups. Adult monarch butterflies raised on treated milkweed were larger than controls, but clothianidin exposure did not affect the number of eggs laid or egg size. Although the magnitude of the effect depends on clothianidin concentration, our results suggest that exposure to clothianidin during early life can impact monarch caterpillar development but is unlikely to reduce female reproductive output.

新烟碱类杀虫剂用于减少虫害对农作物的损害，但亚致死水平可能会影响非目标昆虫的发育和繁殖，例如帝王蝶（Danaus plexippus）（鳞翅目：Nymphalidae）。为了研究新烟碱类可比丁胺的实际浓度对帝王蝶的影响，我们种植了沼泽马利筋（Asclepias incarnata）（夹竹桃科）用低浓度（15 ng / g土壤）或高浓度（25 ng / g土壤）的可比丁或对照（0 ng / g），然后在马利筋上举起君主。帝王毛虫的形态特征在发育过程中进行了测量，一旦它们闭合，成年后就进行交配，以量化卵的大小，质量和产卵的数量。尽管该处理方法对毛虫的长度有复杂的影响，但后期幼虫的宽度和体积却受到负面影响。高剂量杀虫剂处理的五龄毛虫的质量低于其他组。在处理过的乳草上长出的成年帝王蝶比对照大，但可尼丁的暴露量不会影响产卵数或卵大小。尽管影响的程度取决于可比尼丁的浓度，