Huang Zhengyu, Wang Yao, Zhang Yalin
Key Laboratory of Plant Protection Resources & Pest Management, Ministry of Education, College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China.
J Econ Entomol. 2015 Jun;108(3):1054-64. doi: 10.1093/jee/tov057. Epub 2015 Mar 31.
The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a major pest of cruciferous vegetables throughout the world. Cantharidin, a natural toxin isolated from beetles in the families Meloidae and Oedemeridae, has been reported to be toxic to some pests, including the diamondback moth. However, the effects of cantharidin, especially its sublethal effects on development and reproduction of diamondback moth, are less known. In this study, we investigated the sublethal effects of cantharidin at LC2 (0.41 mg liter(-1)), LC10 (1.33 mg liter(-1)), LC25 (3.38 mg liter(-1)), and LC50 (9.53 mg liter(-1)) on development and reproduction parameters of two consecutive diamondback moth generations. The results indicated that cantharidin reduced population growth by decreasing its pupation rate, pupal weight, and adult emergence, and by delaying its development. Furthermore, the duration of the female preoviposition period increased, while the oviposition and postoviposition periods, fecundity, and survival rates of the offspring decreased. The peaks of age-specific fecundity in LC10, LC25, and LC50 treatment groups lagged behind the control group. The mean values of the net reproductive rate (R0), intrinsic rate of increase (r), and finite rate of increase (λ) were significantly lower than those of the control, and the mean generation time (T) was prolonged. The present study demonstrates that cantharidin exhibits significant adverse effects on the population dynamics of diamondback moth, leading to fitness disadvantages.
小菜蛾，即小菜蛾（Plutella xylostella (L.)，鳞翅目：菜蛾科），是全球十字花科蔬菜的主要害虫。斑蝥素是从芫菁科和拟天牛科甲虫中分离出的一种天然毒素，据报道对包括小菜蛾在内的一些害虫有毒性。然而，斑蝥素的影响，尤其是其对小菜蛾发育和繁殖的亚致死效应，却鲜为人知。在本研究中，我们研究了斑蝥素在LC2（0.41毫克/升）、LC10（1.33毫克/升）、LC25（3.38毫克/升）和LC50（9.53毫克/升）剂量下对连续两代小菜蛾发育和繁殖参数的亚致死效应。结果表明，斑蝥素通过降低化蛹率、蛹重和成虫羽化率以及延迟其发育来减少种群增长。此外，雌虫产卵前期延长，而产卵期和产卵后期、繁殖力以及后代存活率降低。LC10、LC25和LC50处理组的特定年龄繁殖力峰值滞后于对照组。净生殖率（R0）、内禀增长率（r）和有限增长率（λ）的平均值显著低于对照组，平均世代时间（T）延长。本研究表明，斑蝥素对小菜蛾的种群动态具有显著的不利影响，导致其适合度下降。
