Abstract Diamide insecticides have been widely used to manage Helicoverpa armigera (Hubner) since the official detection of this pest in Brazil in 2013. Characterizing the baseline susceptibility of H. armigera populations to insecticides is the first step to implement an effective resistance-management program. In this study, we characterized the susceptibility and estimated the frequency of resistance allele to diamide insecticides in populations of H. armigera collected in different Brazilian agricultural regions. First, the baseline susceptibilities to flubendiamide, chlorantraniliprole and cyantraniliprole were established for seven H. armigera populations collected in 2013 and 2014, and the allele frequency of resistance to chlorantraniliprole was estimated using the F2 screening method. Then, the susceptibility to diamide insecticides was monitored based on diagnostic doses (LD99) in H. armigera populations collected from 2014 to 2018. Low initial variations in susceptibility (

中文翻译：

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巴西棉铃虫（鳞翅目：夜蛾科）种群对二酰胺类杀虫剂的基线敏感性和抗性频率

摘要 自 2013 年巴西官方检测到棉铃虫 (Hubner) 以来，二酰胺杀虫剂已被广泛用于防治棉铃虫。表征棉铃虫种群对杀虫剂的基线敏感性是实施有效抗药性管理计划的第一步。在这项研究中，我们描述了在巴西不同农业地区收集的棉铃虫种群中对二酰胺类杀虫剂的敏感性并估计了抗性等位基因的频率。首先，对 2013 年和 2014 年收集的 7 个棉铃虫种群建立了氟虫双酰胺、氯虫苯甲酰胺和氰虫酰胺的基线敏感性，并使用 F2 筛选方法估计了对氯虫苯甲酰胺耐药的等位基因频率。然后，