Department of Entomology, South China Agricultural University, Guangzhou 510642, Guangdong Province, China.
J Econ Entomol. 2012 Aug;105(4):1157-63. doi: 10.1603/ec12042.
The acute toxicity of 10 conventional insecticides to adult of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) was bioassayed by membrane method, and then their sublethal effects on the parasitoid were evaluated in the laboratory. Based on sublethal concentration (LC30) values at 8 h after treatment, we determined that adult T. chilonis were the most susceptible to chlorfenapyr, followed by fipronil, spinosad, avermectins, beta-cypermethrin, and cartap, with lethal concentration (LC)30 values of 0.3133, 0.3269, 1.5408, 3.2961, 6.1469, and 9.021 mg/liter, respectively. The field-recommended concentrations of chlorfluazuron, indoxacarb, Bacillus thuringiensis, and tebufenozide caused <30% mortality of treated adults; therefore, they were used to evaluate sublethal effects on the parasitoid. After treatment with sublethal concentration of fipronil and avermectins, the longevity of treated females (1.2 and 1.6 d) was significantly shortened and fecundity (34.7 and 1.6) was remarkably decreased; consequently, the life-table parameters (R0, r(m), lambda, and T) of T. chilonis were statistically lower than those in the control. Cartap and spinosad also reduced longevity (8 and 7.9 d) and fecundity (110.77 and 117.2) of treated adults, but cartap enhanced the female percentage of F1 offspring (61.6%), resulting a statistical higher R0, r(m), and lambda of treated T. chilonis. In contrast, chlorfluazuron and tebufenozide increased longevity (16.4 and 15.4 d) and fecundity (248 and 256.9) of treated adults but slightly decreased the female percentage of F1 offspring (31.4 and 38.1%). Although chlorfenapyr showed no adverse influence on longevity and fecundity, it remarkably reduced the female percentage of F1 offspring (13.5%), leading to a lower R0, r(m), and lambda of treated T. chilonis. Indoxacarb, B. thuringiensis, and beta-cypermethrin had no obvious sublethal effects on the longevity and fecundity of treated adults. Based on these results, we consider B. thuringienesis, chlorfluazuron, indoxacarb, beta-cypermethrin, and tebufenozide safe to T. chilonis, suggesting that these insecticides are compatible with this parasitoid when being used in the field. However, fipronil, chlorfenapyr, spinosad, and avermectins were very harmful to T. chilonis. Timing of application of these insecticides was critical.
10 种常用杀虫剂对螟黄赤眼蜂成蜂的急性毒性采用膜法生物测定，并在实验室评估了其对寄生蜂的亚致死效应。根据处理后 8 小时的亚致死浓度（LC30）值，我们确定螟黄赤眼蜂对氯氟氰菊酯最敏感，其次是氟虫腈、乙基多杀菌素、阿维菌素、高效氯氟氰菊酯和杀螟丹，LC30 值分别为 0.3133、0.3269、1.5408、3.2961、6.1469 和 9.021 mg/L。氯氟脲、茚虫威、苏云金芽孢杆菌和甲维盐的田间推荐浓度对处理成虫的死亡率<30%；因此，它们被用来评估对寄生蜂的亚致死效应。用亚致死浓度的氟虫腈和阿维菌素处理后，雌蜂的寿命（1.2 和 1.6 天）明显缩短，产卵量（34.7 和 1.6）显著减少；因此，螟黄赤眼蜂的生命表参数（R0、r(m)、λ和 T）明显低于对照。杀螟丹和乙基多杀菌素也降低了处理成虫的寿命（8 和 7.9 天）和产卵量（110.77 和 117.2），但杀螟丹提高了 F1 代雌蜂的比例（61.6%），导致处理后螟黄赤眼蜂的 R0、r(m)和 λ的统计值更高。相比之下，氯氟脲和涕灭威增加了处理成虫的寿命（16.4 和 15.4 天）和产卵量（248 和 256.9），但略微降低了 F1 代雌蜂的比例（31.4 和 38.1%）。氯氟氰菊酯虽然对寿命和产卵量没有不良影响，但显著降低了 F1 代雌蜂的比例（13.5%），导致处理后螟黄赤眼蜂的 R0、r(m)和 λ的统计值较低。茚虫威、苏云金芽孢杆菌和高效氯氟氰菊酯对处理成虫的寿命和产卵量没有明显的亚致死效应。根据这些结果，我们认为苏云金芽孢杆菌、氯氟脲、茚虫威、高效氯氟氰菊酯和涕灭威对螟黄赤眼蜂是安全的，表明这些杀虫剂在田间使用时与这种寄生蜂相容。然而，氟虫腈、氯氟氰菊酯、乙基多杀菌素和阿维菌素对螟黄赤眼蜂非常有害。这些杀虫剂的施用时间非常关键。
