常用杀虫剂对菜蛾绒茧蜂的影响及毒理机制研究

田间采集试虫室内测定结果表明,敌敌畏、灭多威和杀虫双对菜蛾绒茧蜂Apanteles plutellae高毒,乙酰甲胺磷对绒茧蜂毒性较低,而氰戊菊酯、氯氰菊酯、氟虫腈、阿维菌素、定虫隆和Bt则是低毒的。菜蛾绒茧蜂AChE的Km及Vmax值分别是小菜蛾的0.22和2.08倍,AChE对敌敌畏的敏感性(K/em>i值)分别是小菜蛾的10.37倍。100 mg/L的胡椒基丁醚(PB)或磷酸三苯酯(TPP)均可使氰戊菊酯明显增效,其中PB的增效作用显著高于TPP。体内抑制实验结果表明,PB和TPP对绒茧蜂AChE活力无显著影响,低浓度(100 mg/L)的PB即可显著抑制绒茧蜂的α-NA和β-NA CarE活力,且抑制率高于TPP,TPP仅在高浓度(1 000 mg/L)时对绒茧蜂的两种CarE活力有显著抑制作用。由此推断,与小菜蛾相比,菜蛾绒茧蜂对有机磷的高敏感性与其显著较高的AChE敏感性有关;此外,多功能氧化酶的解毒代谢在菜蛾绒茧蜂对氰戊菊酯的耐药性中具重要作用。     

田间菜蛾绒茧蜂对有机磷敏感性监测及毒理机制分析

对甲胺磷敏感性的田间监测结果显示,绒茧蜂存在着抗性演化,毒力生物测定结果与AChE的K_i值的监测结果呈明显的相关性,每年9月至次年2月期间AChE敏感性最低,8月期间敏感性最高。甲胺磷可显著地抑制绒茧蜂AChE、CarE和GSTs的活性。PB和TPP对AChE的活体抑制率极低,但PB可强烈抑制CarE的活性,而TPP仅在高浓度时对CarE有较显著的抑制作用,PB对甲胺磷有显著的增效作用,而TPP对甲胺磷无增效作用。AChE的K_m、V_(max)及K_i值研究结果表明,田间绒茧蜂对有机磷和氨基甲酸酯的抗性与AChE对杀虫剂的不敏感性有关。由此认为,绒茧蜂对有机磷的抗性主要与其最重要的靶标酶AChE的敏感性改变及多功能氧化酶有关。     

小菜蛾对阿维菌素的抗性机制及交互抗性研究

用叶片药膜法研究了阿维菌素抗性小菜蛾 Plutella xylostella （L.）品系 对常用药剂的交互抗性谱以及增效醚（PB）和磷酸三苯酯（TPP）的增效作用。小菜蛾对阿 维菌素与高效氯氰菊酯、溴氰菊酯、氰戊菊酯和联苯菊酯等菊酯类药剂间具有比较低的交互 抗性，对后者抗性为3～20倍，对阿维菌素的抗性为575.6倍；对氟虫脲和氟啶脲没有交互抗 性。PB和TPP对阿维菌素分别增效8.2和5.5倍，说明小菜蛾对阿维菌素的抗性可能与多功能 氧化酶（MFO）和羧酸酯酶有关。通过差光谱技术测定了阿维菌素抗性和敏感小菜蛾细胞色 素P450的含量，抗性品系是敏感品系的1.38倍。     

不同类型药剂对水稻褐飞虱的活性及复配增效作用

采用稻茎浸渍法测定了18种杀虫剂对褐飞虱的毒力,选活性较好的药剂进行复配,筛选出具有较高活性的混剂,测定不同类型增效剂的增效作用与复合增效作用,并研究混剂与复合增效剂的最佳增效配伍。结果表明,18种药剂对褐飞虱的毒力大小次序为:氟虫腈噻嗪酮烯啶虫胺氟铃脲噻虫嗪甲维盐吡蚜酮阿维菌素丁醚脲毒死蜱速灭威啶虫脒异丙威联苯菊酯吡虫啉高效氯氟氰菊酯三唑磷马拉硫磷,其中氟虫腈的活性最高,是吡虫啉的128.38倍。不同药剂复配中,烯啶虫胺与噻嗪酮(30∶70)复配的共毒系数最高,为246.02。6种增效剂与药剂混配增效作用,以氮酮、有机硅最好,增效比在2.69~2.85之间,并且将两者按40∶60配比后,其联合增效作用有显著提高。     

褐飞虱对氟啶虫胺腈的抗性监测与生化抗性机制

为明确我国褐飞虱田间种群对氟啶虫胺腈的抗性现状及生化抗性机制,2017年-2019年采用稻茎浸渍法测定了采集自7省共13个褐飞虱田间种群对氟啶虫胺腈的抗性,并研究了氟啶虫胺腈抗性种群与其他杀虫剂的交互抗性以及增效剂对氟啶虫胺腈的增效效果。结果表明：近3年来褐飞虱对氟啶虫胺腈产生了中等水平抗性(RR=10.3～30.9)。氟啶虫胺腈抗性品系对呋虫胺、噻虫嗪和烯啶虫胺分别产生了9.1倍、7.9倍和4.1倍的低水平交互抗性,与噻嗪酮、毒死蜱、吡蚜酮、三氟苯嘧啶和吡虫啉不存在交互抗性。增效剂PBO对氟啶虫胺腈抗性品系和浙江龙游19(Longyou-19)田间种群分别具有4.2倍和3.8倍的明显增效作用。综上,褐飞虱田间种群已对氟啶虫胺腈产生中等水平抗性。多功能氧化酶参与了褐飞虱对氟啶虫胺腈的代谢抗性。     

陕西关中地区小麦田禾谷缢管蚜对7种杀虫剂的抗性监测

为明确陕西关中地区麦蚜田间种群对杀虫剂的抗药性现状,采用浸叶法测定了兴平、礼泉、凤翔、岐山、扶风地区麦田禾谷缢管蚜种群对高效氯氰菊酯、溴氰菊酯、吡虫啉、异丙威、毒死蜱、阿维菌素、氟啶虫胺腈等7种杀虫剂的抗性水平。结果表明,禾谷缢管蚜对高效氯氰菊酯的抗性水平最高,其中凤翔种群对高效氯氰菊酯达到高水平抗性(抗性倍数为72.5),岐山和扶风种群对该药产生中等水平抗性(抗性倍数分别为31.4、29.9);5个地区的禾谷缢管蚜对溴氰菊酯、吡虫啉、毒死蜱、异丙威和阿维菌素的抗性水平较低,表现为敏感、敏感性下降或者低抗性;5个地区的试虫对氟啶虫胺腈均表现为敏感。分析认为,高效氯氰菊酯不适合用于关中地区禾谷缢管蚜防治,氟啶虫胺腈作为一种新型杀虫剂,可以在该虫防治中推广使用,吡虫啉、阿维菌素等其他几种杀虫剂可以在禾谷缢管蚜的防治中交替使用。     

增效剂对桔小实蝇抗药性的影响

采用药膜法分别测定了增效醚(PBO)和磷酸三苯酯(TPP)两种增效剂对桔小实蝇抗敌百虫、高效氯氰菊酯和阿维菌素三个种群的抗药性产生的影响。结果表明,对这三种药剂分别产生的桔小实蝇抗性种群,PBO和TPP均能对其抗药性有一定的影响,但影响程度不同,对抗敌百虫、抗高效氯氰菊酯的两个桔小实蝇种群,TPP对敌百虫和高效氯氰菊酯的增效作用均高于PBO,且增效作用显著,增效比分别达3.98和2.43,PBO的增效比为1.71和1.66;对抗阿维菌素的桔小实蝇种群则略相反,PBO对阿维菌素的增效作用高于TPP,但增效作用均低于敌百虫与高效氯氰菊酯。     

小菜蛾对阿维菌素的抗性选育及交互抗性研究

用阿维菌素对小菜蛾进行室内抗性汰选,选择压为约杀死种群70％的剂量。连续施药7～8次即表现抗性趋势,汰选至11代,获得抗性指数为80.71的抗性种群(ABM-R)。ABM-R种群对所测试的有机磷杀虫剂乙酰甲胺磷、有机氯类的硫丹、沙蚕毒素类的杀螟丹、氨基甲酸酯类的灭多威、微生物杀虫剂Bt、磺胺脲类衍生物丁醚脲、芳基取代的吡咯杂环化合物虫螨腈和昆虫生长调节剂定虫隆、虫酰肼无交互抗性(R/S为0.73～1.19),而对苯基吡唑类氟虫腈的敏感性却有所上升(R/S为0.22)。增效剂试验显示,PB和唧对ABM-S种群无增效作用,而对ABM-R种群增效作用显著,增效比分别为24.57和13.61,表明多功能氧化酶和羧酸酯酶在抗性机制中可能起重要作用。     

盆栽花卉红火蚁药剂处理试验初报

高效氯氰菊脂、氯氰菊酯、溴氰菊酯、氰戊菊酯、高效氯氟氰菊酯、阿维菌素、氟虫腈和毒死蜱等8种杀虫剂浇灌处理盆栽花卉的红火蚁蚁巢试验证明:4.5%高效氯氰菊酯乳油和2.5%溴氰菊酯乳油800倍稀释液、20%氰戊菊酯乳油和1.8%阿维菌素乳油2000倍稀释液均能在3天内完全杀灭蚁巢内的工蚁、兵蚁、有翅繁殖蚁和蚁后;对花卉生长没有不良影响,可用于携带红火蚁盆花的应急检疫除害处理;其余4种农药不能达到快速杀灭红火蚁的要求.     

棉蚜吡虫啉、啶虫脒不同品系解毒酶活性测定和增效剂作用的研究

通过棉蚜Aphis gossypii吡虫啉和啶虫脒抗性、敏感品系解毒酶活性测定和增效剂试验,明确与抗药性产生密切相关的解毒酶。采用室内生物测定和生化分析方法,研究棉蚜吡虫啉和啶虫脒品系解毒酶活性变化和增效剂的增效作用。解毒酶活性测定表明,棉蚜吡虫啉和啶虫脒抗性品系羧酸酯酶、谷胱甘肽-S-转移酶、细胞色素P450s O-脱乙基比活力都高于敏感品系,其中抗感品系中羧酸酯酶、细胞色素P450-O-脱乙基比活力差异都达到了显著水平(P0.05)。吡虫啉抗性品系三种解毒酶活性分别为敏感品系的3.26倍、1.08倍、1.60倍和1.58倍;啶虫脒抗性品系三种解毒酶活性分别为敏感品系的2.91倍、1.04倍、1.69倍和1.46倍。增效剂磷酸三苯酯(TPP)、增效醚(PBO)、顺丁烯二酸二乙酯(DEM),在吡虫啉敏感品系中的增效比分别为1.12、1.09、0.97,在吡虫啉抗性品系中的增效比分别为2.02、1.75、1.05;在啶虫脒敏感棉蚜品系中的增效比为1.02、1.03、1.02,在啶虫脒抗性棉蚜品系中的增效比为1.77、1.61、1.04。增效剂试验和解毒酶试验表明,酯酶和多功能氧化酶在棉蚜对吡虫啉、啶虫脒的抗性产生中起到了重要的作用。     

杀虫增效剂--酶抑制剂对蝶蛹金小蜂和颈双缘姬蜂的影响

采用药膜法测定了3种酶抑制剂对蝶蛹金小蜂和颈双缘姬蜂杀虫剂敏感性的影响。结果表明，胡椒基丁醚、磷酸三苯酯和马来酸二乙酯显著增大了蝶蛹金小蜂和颈双缘姬蜂对甲胺磷、氰戊菊酯、氯氰菊酯、氟虫腈和阿维菌素的敏感性，胡椒基丁醚的作用显著高于后两者，而后两者之间较为接近。2种寄生蜂对氰戊菊酯和氯氰菊酯的击倒作用具明显的恢复能力，而胡椒基丁醚、磷酸三苯酯和马来酸二乙酯可显著抑制这种击倒恢复能力。上述结果表明，2种寄生蜂对所测试杀虫剂的耐药性与多功能氧化酶、羧酸酯酶和谷胱甘肽-S-转移酶的解毒作用有关，其中多功能氧化酶的作用可能是最重要的。     

Insecticide toxicity and synergism by enzyme inhibitors in 18 species of pest insect and natural enemies in crucifer vegetable crops

The toxicities of three enzyme inhibitors and their synergistic effects on four insecticides were studied by using the dry film method on field populations of 18 species of insects collected in Jianxin and Shanjie, China, from 2003 to 2005. Meanwhile, the inhibitory effects of these enzyme inhibitors on the activities of acetylcholinesterases (AChE), carboxyesterases (CarE) and glutathione-S-transferases (GST), in vivo, were also studied. In general, triphenyl phosphate (TPP) and diethyl maleate (DEM) showed low toxicities to six herbivorous pest insects, four ladybirds and eight parasitoids. Piperonyl butoxide (PB) exhibited low toxicities to the herbivorous pest insects and ladybirds, but high toxicities to the eight parasitoids. The tolerance to the insecticides in 11 pest insects and natural enemies was mainly associated with the tolerance to PB. PB showed the highest synergism on methamidophos, fenvalerate, fipronil and avermectin in nine species of pest insects and natural enemies. In general, TPP and DEM showed significant synergisms to these four insecticides in four parasitoid species. However, in contrast to their effects on the parasitoids, the synergistic effects of TPP and DEM on the four insecticides by TPP and DEM against four pest insects and one ladybird varied depending on the insect species and enzyme inhibitor. Activity of AChE, CarE or GST could be strongly inhibited, in vivo, by PB, TPP or DEM, depending on the insect species and enzyme inhibitors. From the results obtained in this study, mixed-function oxidase (MFO) was thought to play the most critical role in insect tolerances to the tested insecticides in the field. Low competition existed in the evolution of insecticide resistance in the field populations of parasitoids, as compared with herbivorous pest insects and ladybirds. Possible causes of the high synergistic effects of PB on the four classes of insecticides, based on multiattack on the activity of CarE, GST or AChE in the insect species, are also discussed.     

Susceptibilities to methamidophos and enzymatic characteristics in 18 species of pest insects and their natural enemies in crucifer vegetable crops

The susceptibilities to methamidophos as well as the kinetic and inhibitory parameter of acetylcholinesterases (AChE) and the activities of carboxyestsrases (CarE) and glutathione-S-transferases (GST) were studied in 18 species field populations of insects collected in Fuzhou, China during April and May 2000 and 2001. The insect species included five hymenopteran endoparasitoids, one hymenopteran exoparasitoid, one hymenopteran hyperparasitoid, one dipteran predator, four coleopteran predator ladybirds, six herbivorous pest insects of lepidoptera, diptera, homoptera, and coleoptera, respectively. There existed significant correlations between the susceptibility to methamidophos and the k_i values of AChE to methamidophos, dichlorvos, and carbofuran and between the k_i and V_max values of AChE among 18 species of insects. The six herbivorous pests and four ladybirds showed significantly low k_i and V_max values of AChE compared to the seven parasitoids and predator Epistrophe balteate. It was difficult to correlate the susceptibility to methamidophos or the k_i values with the K_m values of AChE, or with the activity of CarE and GST. The activities of CarE and GST varied depending on the different insect species. Significant synergisms of piperonyl butoxide (PB), triphenyl phosphate (TPP), and diethyl maleate (DEM) with methamidophos were observed in 14 pest insects and their natural enemies. Synergisms of PB were found to be the greatest. Reduced k_i values suggested that insensitive AChE might play a critical role in the tolerance to methamidophos in the 18 insect species. The detoxification enzymes, mixed-function oxidase (MFO), CarE, and GST, were believed to be involved in the tolerance to methamidophos. MFO might play the most important role, and CarE or GST might be important in the tolerance in some insect species. Different models of tolerance to methamidophos and enzymatic potential were existed in parasitoids, predators, and herbivores based on the different selection of insecticide pressure (either directly by exposing to the spray in the field, or indirectly by the insecticides penetrated into the body of host insects) as well as different ecological and biological habitats.     

山东省不同地区棉蚜对新烟碱类杀虫剂的抗药性检测及酶抑制剂的增效作用研究

为明确山东省棉蚜对新烟碱类杀虫剂的抗性水平,采用毛细管微量点滴法测定了泰安、聊城和东营3个田间种群及1个敏感种群对吡虫啉、烯啶虫胺、啶虫脒、噻虫嗪、噻虫啉、噻虫胺6种新烟碱类杀虫剂的敏感性,同时测定了磷酸三苯酯(TPP)、顺丁烯二酸二乙酯(DEM)和增效醚(PBO)3种酶抑制剂的增效作用。结果表明:泰安棉蚜种群对烯啶虫胺的抗性倍数为16.95,处于中等抗性水平,对吡虫啉和啶虫脒的抗性倍数分别为5.69和9.57,已产生低水平抗性,对噻虫胺、噻虫嗪和噻虫啉的抗性倍数均小于3.0,仍较敏感;聊城棉蚜种群对吡虫啉、啶虫脒和噻虫嗪的抗性倍数分别为28.51、25.88和18.16,属中等抗性水平,对噻虫啉和噻虫胺的抗性倍数分别为6.01和6.37,已产生低水平抗性,对烯啶虫胺仍处于敏感阶段;东营棉蚜种群对吡虫啉、啶虫脒和噻虫胺的抗性倍数分别为37.95、21.52和12.95,已产生中等水平抗性,对噻虫啉、烯啶虫胺和噻虫嗪的抗性倍数分别为7.07、6.38和4.75,处于低水平抗性阶段。多功能氧化酶抑制剂PBO和羧酸酯酶抑制剂TPP对6种供试新烟碱类杀虫剂的增效作用明显,谷胱甘肽-S-转移酶抑制剂DEM对这6种药剂也具有一定的增效作用。研究表明,山东省泰安等3地区棉蚜种群对6种新烟碱类杀虫剂均产生了不同程度的抗药性,多功能氧化酶和羧酸酯酶可能在棉蚜对该类杀虫剂的抗性中起主要作用,谷胱甘肽-S-转移酶可能也具有一定的作用。     

茚虫威对草地贪夜蛾的毒力及解毒酶的诱导作用

茚虫威对鳞翅目害虫幼虫具有卓越的杀虫活性,是替代传统杀虫剂及治理抗药性害虫的理想药剂。为了明确茚虫威对草地贪夜蛾的生物活性及对其主要解毒酶活性的影响,为使用茚虫威科学防治草地贪夜蛾提供参考,本研究采用浸叶法测定了广西南宁草地贪夜蛾种群3龄幼虫对茚虫威敏感性及增效醚(PBO)、磷酸三苯酯(TPP)、顺丁烯二酸二乙酯(DEM)对茚虫威的增效作用;并测定了亚致死浓度(LC_(20))茚虫威对草地贪夜蛾体内MFO、GSTs和CarE酶的诱导作用。结果表明,茚虫威对草地贪夜蛾的LC_(20)、LC_(50)和LC_(90)分别为8.95、20.62 mg/L和73.57 mg/L。DEM、PBO和TPP对茚虫威的增效倍数依次为2.24、2.05和0.50倍。亚致死浓度(LC_(20))茚虫威处理后对3龄幼虫体内GSTs的活性和MFO含量与无药剂处理(CK)相比显著升高(P0.05),而CarE活性无显著变化(P0.05)。本文结果显示,广西草地贪夜蛾仍可以用推荐剂量80 mg/L茚虫威防治,而代谢抑制剂PBO和DEM对茚虫威有明显的增效作用,且GSTs活性和MFO含量在茚虫威诱导后显著升高,初步推测这两种解毒酶可能影响将来草地贪夜蛾对茚虫威的抗药性发展。     

辛氰和乐氰混剂对甘蓝桃蚜抗性演化的影响

用辛硫磷与氰戊菊酯,乐果与氰戊菊酯的最佳配比及其相应单剂对甘蓝桃蚜进行抗性选育,汰洗２０代时桃蚜对两种混剂的抗性,分别为４．２０和２．６８倍,比相应单剂的抗性发展速度慢,尤其比氰戊菊酯单剂（２８９倍）更慢,表明上述两种混剂都可延缓桃蚜的抗性发展。用酶抑制剂进行增效应用测定结果表明：Ｋ１和ＴＰＰ对辛硫磷和乐果都有增效作用,尤以Ｋ１的增效作用更显著,其增效比分中辊为１０５３和３８,说明桃蚜对辛硫磷和乐     

Identification and expression profiles of nine glutathione S-transferase genes from the important rice phloem sap-sucker and virus vector Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae)

BACKGROUND: Glutathione S‐transferases (GSTs) have received considerable attention in insects for their roles in insecticide resistance. Laodelphax striatellus (Fallén) is a serious rice pest. L. striatellus outbreaks occur frequently throughout eastern Asia. A key problem in controlling this pest is its rapid adaptation to numerous insecticides. In this research, nine cDNAs encoding GSTs in L. striatellus were cloned and characterised. RESULTS: The cloned GSTs of L. striatellus belonged to six cytosolic classes and a microsomal subgroup. Exposure to sublethal concentrations of each of the six insecticides, DDT, chlorpyrifos, fipronil, imidacloprid, buprofezin and beta‐cypermethrin, quickly induced (6 h) up‐expression of LsGSTe1. The expression of LsGSTs2 was increased by chlorpyrifos, fipronil and beta‐cypermethrin. Furthermore, exposure of L. striatellus to fipronil, imidacloprid, buprofezin and beta‐cypermethrin increased the expression of the LsGSTm gene after 24 or 48 h. CONCLUSION: This work is the first identification of GST genes from different GST groups in Auchenorrhyncha species and their induction characteristics with insecticide types and time. The elevated expression of GST genes induced by insecticides might be related to the enhanced tolerance of this insect to insecticides and xenobiotics. Copyright © 2012 Society of Chemical Industry