Jiang Jiangong, Zhang Zhengqun, Yu Xin, Yu Caihong, Liu Feng, Mu Wei
College of Plant Protection, Key Laboratory of Pesticide Toxicology & Application Technique, Shandong Agricultural University, Tai'an, Shandong 271018, China.
College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China.
Chemosphere. 2019 Feb;216:168-178. doi: 10.1016/j.chemosphere.2018.10.126. Epub 2018 Oct 18.
Seven-spot ladybird beetles, Coccinella septempunctata L., are critical aphidophagous predators in the agricultural environment. Thiamethoxam, a neonicotinoid insecticide, is commonly used for controlling pests but impairs their natural enemies at the same time. To improve effective IPM (integrated pest management) strategies, we evaluated the sublethal and transgenerational effects of thiamethoxam on C. septempunctata. Our results showed that thiamethoxam at doses of 0.1 × LC (0.053 mg L) and LC (0.53 mg L) significantly reduced adult emergence, fecundity and fertility of the parental generation. In unexposed progeny (F) of thiamethoxam-exposed parents, at the two doses 0.1 × LC and LC, the larval stage was prolonged, and total longevity was decreased by 18.76 and 24.46%, respectively. The higher concentrations (0.1 × LC and LC) also decreased the fecundity by 33.74 and 46.56%, respectively, and the oviposition period by 19.67 and 25.01%, respectively. In addition, demographic parameters including the intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R), and mean generation time (T) were significantly reduced when exposed to LC. Moreover, the predation activity of the F generation was reduced by the transgenerational effects of LC. These results disclose negative influence of thiamethoxam at sublethal concentrations on this ladybird predator and its subsequent generation.
七星瓢虫（Coccinella septempunctata L.）是农业环境中重要的捕食蚜虫的天敌。噻虫嗪是一种新烟碱类杀虫剂，常用于控制害虫，但同时也会损害其天敌。为了改进有效的综合虫害管理（IPM）策略，我们评估了噻虫嗪对七星瓢虫的亚致死效应和跨代效应。我们的结果表明，剂量为0.1×LC（0.053 mg/L）和LC（0.53 mg/L）的噻虫嗪显著降低了亲代的成虫羽化率、繁殖力和生育力。在噻虫嗪暴露亲代的未暴露后代（F1）中，在0.1×LC和LC这两个剂量下，幼虫期延长，总寿命分别降低了18.76%和24.46%。较高浓度（0.1×LC和LC）也分别使繁殖力降低了33.74%和46.56%，产卵期分别缩短了19.67%和25.01%。此外，当暴露于LC时，包括内禀增长率（r）、有限增长率（λ）、净繁殖率（R）和平均世代时间（T）在内的种群统计学参数显著降低。此外，LC的跨代效应降低了F1代的捕食活性。这些结果揭示了亚致死浓度的噻虫嗪对这种瓢虫天敌及其后代的负面影响。
