Prabhaker Nilima, Naranjo Steven, Perring Thomas, Castle Steven
Department of Entomology, University of California.
USDA-ARS, Arid-Land Agricultural Research Center.
J Econ Entomol. 2017 Dec 5;110(6):2630-2636. doi: 10.1093/jee/tox202.
Generalist insect predators play an essential role in regulating the populations of Bemisia tabaci and other pests in agricultural systems, but may be affected negatively by insecticides applied for pest management. Evaluation of insecticide compatibility with specific predator species can provide a basis for making treatment decisions with the aim of conserving natural enemies. Eleven insecticides representing six modes of action groups were evaluated for toxicity against four predator species and at different developmental stages. Full-concentration series bioassays were conducted on laboratory-reared or insectary-supplied predators using Petri dish and systemic uptake bioassay techniques. Highest toxicities were observed with imidacloprid and clothianidin against first and second instar nymphs of Geocoris punctipes (Say) (Hemiptera: Geocoridae). Later instar nymphs were less susceptible to neonicotinoid treatments based on higher LC50s observed with imidacloprid, thiamethoxam, and dinotefuran against third or fourth instar nymphs. The pyrethroid insecticide bifenthrin was highly toxic against adults of G. punctipes and Orius insidiosus (Say) (Hemiptera: Anthocoridae). Standard concentration/mortality evaluation of nonacute toxicity insecticides, including buprofezin, pyriproxyfen, spirotetramat, and spiromesifen, was inconclusive in terms of generating probit statistics. However, low mortality levels of insects exposed for up to 120 h suggested minimal lethality with the exception of pyriproxyfen that was mildly toxic to Chrysoperla rufilabris (Burmeister) (Neuroptera: Chrysopidae).
多食性昆虫捕食者在调控农业系统中烟粉虱及其他害虫种群方面发挥着重要作用，但可能会受到用于害虫防治的杀虫剂的负面影响。评估杀虫剂与特定捕食者物种的兼容性可为做出旨在保护天敌的防治决策提供依据。对代表六种作用方式组的11种杀虫剂针对四种捕食者物种及其不同发育阶段的毒性进行了评估。使用培养皿和系统吸收生物测定技术，对实验室饲养或昆虫饲养室提供的捕食者进行了全浓度系列生物测定。观察到吡虫啉和噻虫胺对点蜂缘蝽（Say）（半翅目：缘蝽科）一龄和二龄若虫毒性最高。基于吡虫啉、噻虫嗪和呋虫胺对三龄或四龄若虫观察到的较高半数致死浓度（LC50），后期若虫对新烟碱类处理的敏感性较低。拟除虫菊酯类杀虫剂联苯菊酯对点蜂缘蝽成虫和暗黑赤眼蜂（Say）（半翅目：花蝽科）毒性很高。包括噻嗪酮、吡丙醚、螺虫乙酯和螺甲螨酯在内的非急性毒性杀虫剂的标准浓度/死亡率评估在生成概率统计方面尚无定论。然而，暴露长达120小时的昆虫低死亡率表明除吡丙醚对红肩瓢虫（Burmeister）（脉翅目：草蛉科）有轻度毒性外，致死率极低。
