拟除虫菊酯类杀虫剂对蜜蜂的毒性和影响

蜜蜂是最重要的农业授粉昆虫之一,蜜蜂在授粉过程中极有可能接触到广泛使用的广谱杀虫剂-拟除虫菊酯,大多数拟除虫菊酯对蜜蜂等农业授粉昆虫有较高的毒性.本文对拟除虫菊酯类杀虫剂的作用机理进行了综述;总结了蜂群及蜂产品中拟除虫菊酯类杀虫剂的残留现状、拟除虫菊酯对蜜蜂的急性毒性以及亚致死效应,讨论了拟除虫菊酯类杀虫剂复配农药对蜜...     

钠离子通道与蜜蜂狄斯瓦螨对氟胺氰菊酯的抗性机理

狄斯瓦螨Varroadestructor是全世界蜜蜂最严重的寄生虫 ,目前 ,它对主要防治药物———拟除虫菊酯类的氟胺氰菊酯已产生明显抗性 ,严重影响其防治效果。近年来神经生理学研究结果证实 :电压门控的钠离子通道是拟除虫菊酯作用的位点。钠通道结构的改变 ,是拟除虫菊酯类杀虫剂毒理的主要基础 ,也是产生抗药性的基础。该文介绍了近年来国内外研究电压门控钠离子通道、拟除虫菊酯对钠通道的作用、钠通道与拟除虫菊酯的抗性和狄斯瓦螨对氟胺氰菊酯抗性机理研究的新进展     

拟除虫菊酯对天敌昆虫的影响

<正> 农用拟除虫菊酯是七十年代新发展的仿生农药,对多种害虫具有优良的防治效果,国内已广泛应用于农业害虫的防治,但对天敌昆虫的影响,各地反应不一。为了对拟除虫菊酯对天敌昆虫的毒性有一个初步的认识,以便更好地使用这类农药,现将拟除虫菊酯对一些重要的天敌类群的杀虫作用综述于后,以供参考。 一、寄生峰 过去,一些传统的杀虫剂常常大量杀死寄生蜂,引起害虫再增猖獗。拟除虫菊酯则是一类对寄生性天敌较为安全的新农药。 Waddill(1978)以四种拟除虫菊酯用泸纸药膜法对五种寄生蜂进行了研究后指出,高剂量的杀灭菊酯(90.7克/0.405公顷,有效剂量,下同)对寡节小蜂Diglyphus intermedius、小茧蜂Opius bruneipes及绒茧蜂Apanteles sp.几乎无毒,但对跳小蜂Copidosoma     

拟除虫菊酯对家蝇Ca—ATPase和Ca—Mg—ATPase的抑制作用

通过对家蝇神经系统的Ca-ATPase、Ca-Mg-ATPase性质的研究,表明Ca-ATPase、Ca-Mg-AT-Pase反应的适宜pH值分别为7.0-8.5和6.5。适温皆为35-40℃;底物（ATP）最适浓度均为0.5mmol/L。比较测定了家蝇三个品系中两种ATPase的活性及拟除虫菊酯对该酶的抑制作用,实验证明,敏感与Del-R、2Cl-R品系间Ca-ATPase、Ca-Mg-ATPase活力无明显的差异。溴氰菊酯、氯菊酯可部分地抑制敏感品系家蝇Ca-ATPase活性,而对拟除虫菊酯抗性品系Ca-ATPase无抑制作用,从而证明,Del-R、2Cl-B品系Ca-ATPase对拟除虫菊酯的敏感性已明显降低,这可能能是击倒抗性机制之一。实验还表明,拟除虫菊酯对Ca-Mg-ATPase基本上无抑制作用,这说明在家蝇中,Ca-Mg-ATPase并不是拟除虫菊酯的一个靶标位点。     

拟除虫菊酯杀虫剂的分子毒理学研究进展

<正> 近年来杀虫剂毒理学研究十分活跃,这不仅仅因为合成杀虫剂是现代植物保护与卫生防疫中应用最广和最有效的手段,而且杀虫剂应用本身所带来的抗药性和环境生态的污染问题也促进了对杀虫剂毒理的研究,而现代生物技术的不断发展与渗透则为杀虫剂毒理在整体、细胞和分子三个水平上展开全方位研究创造了条件。在目前使用的杀虫剂中,应用最多的是拟除虫菊酯,由于它的高效低残毒及广谱性、正在越来越多地用于各种害虫防治,据报道它的用量已约占全世界农药量的1/3左右,而且每年正以10％的增长率发展,但是拟除虫菊酯也存在着易于产生抗性以及对天敌缺乏选择性等问题,因此研究拟除虫菊酯作用的分子机理不     

某些杀虫剂对数种寄生蜂的触杀活性

以不同类型的十三种杀虫剂对菜田三种寄生蜂(凤蝶金小峰、菜粉蝶绒茧蜂和啮小蜂)进行了室内触杀活性研究.拟除虫菊酯类杀虫剂对寄生蜂的击倒速度,通常较有机磷制剂快,但其杀虫活性较有机磷制剂小.在四种拟除虫菊酯中,杀灭菊酯和中西除虫菊酯对凤蝶金小蜂的毒性,较氯氰菊酯和二氯苯醚菊酯小.马拉硫磷对凤蝶金小蜂的击倒速度最快.乙酰甲胺磷等七种有机磷制剂对凤蝶金小蜂的活性都很大.微生物制剂浏阳霉素对凤蝶金小蜂无杀虫活性,但和乐果复配后.杀虫活性明显增加.在试验条件下,凤蝶金小蜂接触4.35×10^-4毫克/平方厘米药膜后,开始击倒的速度顺序为:马拉硫磷>氯氰菊脂二氯苯醚菊酯>中西除虫菊酯>敌百虫氧化乐果>甲胺磷>乙酰甲胺磷;活性顺序为:氧化乐果>马拉硫磷甲胺磷>敌百虫乙酰甲胺磷>氯氰菊酯二氯苯醚菊酯>中西除虫菊酯.杀灭菊酯对菜粉蝶绒茧蜂的击倒速度较三唑磷快,但活性较三唑碟小.杀灭菊酯和中西除虫菊酯对菜粉蝶绒茧蜂的重寄生蜂啮小蜂的活性较三唑磷小.接触拟除虫菊酯后,个别中寄或死亡的风蝶金小蜂和啮小蜂,有缓解现象.     

南京地区小菜蛾的抗药性检测及初步分析

利用浸叶法对南京郊区小菜蛾Plutella xylostella的抗药性进行了监测,发现其对拟除虫菊酯类药剂的抗性较高,而对氟虫腈、辛硫磷、毒死蜱、多杀菌素和虫酰肼依然处于敏感阶段。利用抗性小菜蛾测试发现,氧化胡椒基丁醚（增效醚,简称PBO）对拟除虫菊酯具有显著的增效作用。室内敏感性恢复实验表明,在不接触药剂的条件下,小菜蛾对拟除虫菊酯的抗性迅速下降,繁殖10代以后,抗性维持在低抗水平。因此, 小菜蛾的抗药性治理,应充分利用不同药剂的轮换使用,避免单一使用某一品种,以延缓抗性的发展,同时可以利用PBO增强拟除虫菊酯的防治效果,保证这类药剂在小菜蛾防治中的作用。     

家蝇对拟除虫菊酯抗性机理研究进展

本文概述了家蝇对拟除虫菊酯的抗性机制 ,特别是结合我国室内培育的抗拟除虫菊酯家蝇品系 (Dec R和 2Cl R) ,探讨了Na+通道、神经递质释放、ATPase、蛋白质磷酸化等与家蝇Kdr抗性的关系 ,从多方面证明了神经敏感性降低是家蝇对拟除虫菊酯产生抗性的重要机制。     

新农药二氯苯醚菊酯试制简讯

1975年3月我所职工在党支部的正确领导下,以阶级斗争为纲,坚持党的基本路线,独立自主,自力更生,合成出适用于防治农业害虫的新杀虫剂二氯苯醚菊酯。一年多来经过农业科研部门对水稻、棉花、蔬菜、甘薯、茶叶等主要作物害虫的初步试验表明,二氯苯菊醚酯是一种高效低毒颇有发展前途的广谱新杀虫剂。 二氯苯醚菊酯的杀虫性能及化学结构,与除虫菊酯类似,而残效较长,是当代拟除虫菊酯中第一个能用于防治农业害虫的品种,系英国首先试制成功的。二氯苯醚菊酯的化学名称为3-苯氧基     

害虫的抗药性:Ⅶ.昆虫对拟除虫菊酯抗性机理

<正> 合成的拟除虫菊酯类杀虫剂是近年来新发展的高效低残毒杀虫剂,它们对哺乳动物和昆虫的选择毒性要比有机磷、氨基甲酸醋类杀虫剂高出二个数量级,可以说是化学防治中崛起的新星。在70年代初,拟除虫菊酯作为商品问世之初,人们曾根据昆虫似乎对天然除虫菊酯抗性发展较慢的情况预测到昆虫也许不易对     

BEDNET TREATMENT WITH PYRETHROIDS FOR MOSQUITO CONTROL IN CHINA

Abstract  BedHnet treatment with pyrethroids, either by impregnation or by spraying, has been considered as an important progress in vector control in antimalarial programmes. Since last decade, the method has been extensively adopted for malarial control in China. The present paper is a review of the results of laboratory studies, experimental evaluations and field trials and applications of bednet treatment in this country. Some comments are also given to the results in this respect. It is concluded that the bednet treatment with pyrethroids, particularly with deltamethrin, is a feasible community based prevention measure. It can be recommanded to replace DDT indoor residual sprays for vector control in most areas of low and moderate malaria endemicity.     

Combined pyrethroid and carbamate 'two-in-one' treated mosquito nets: field efficacy against pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus

A new approach is proposed in the treatment of mosquito nets, using a 'two-in-one' combination of pyrethroid and non-pyrethroid insecticides applied to different parts of bednets. The objectives are mainly to overcome certain limitations of pyrethroid-impregnated bednets currently recommended for malaria control purposes. Apart from developing alternatives to pyrethroid dependency, we sought to counteract pyrethroid irritant effects on mosquitoes (excito-repellency) and resistance to pyrethroids. The idea takes advantage of the presumed host-seeking behaviour of mosquitoes confronted by a net draped over a bed, whereby the mosquito may explore the net from the top downwards. Thus, nets could be more effective if treated on the upper part with residual non-irritant insecticide (carbamate or organophosphate) and with a pyrethroid on the lower part. Sequential exposure to different insecticides with distinct modes of action is equivalent to the use of a mixture as a potential method of managing insecticide resistance. We also intended to improve the control of nuisance mosquitoes, especially Culex quinquefasciatus Say (Diptera: Culicidae) that often survive pyrethroids, in order to encourage public compliance with use of insecticide-treated nets (ITNs). Polyester bednets were pretreated with residual pyrethroid (bifenthrin 50 mg/m2 or deltamethrin 25 mg/m2) on the lower half and with carbamate (carbosulfan 300 mg/m2) on the upper half to minimize contact with net users. Unreplicated examples of these 'two-in-one' treated nets were field-tested against wild mosquitoes, in comparison with an untreated net and bednets treated with each insecticide alone, including PermaNet wash-resistant formulation of deltamethrin 50 mg/m2. Overnight tests involved volunteers sleeping under the experimental bednets in verandah-trap huts at Yaokofikro, near Bouaké in C te d'Ivoire, where the main malaria vector Anopheles gambiae Giles, as well as Culex quinquefasciatus Say, are highly resistant to pyrethroids. Efficacy of these ITNs was assessed in the huts by four entomological criteria: deterrency and induced exophily (effects on hut entry and exit), blood-feeding and mortality rates (immediate and delayed). Overall, the best impact was achieved by the bednet treated with carbosulfan alone, followed by 'two-in-one' treatments with carbosulfan plus pyrethroid. Blood-feeding rates were 13% An. gambiae and 17% Cx. quinquefasciatus in huts with untreated nets, but only 3% with carbosulfan ITNs, 7-11% with combined ITN treatment, 6-8% An. gambiae and 12-14% Cx. quinquefasciatus with pyrethroid alone. Mosquitoes that entered the huts were killed sooner by nets with combined treatment than by pyrethroid alone. Mortality-rates in response to ITNs with carbosulfan (alone or combined with pyrethroid) were significantly greater for Cx. quinquefasciatus, but not for An. gambiae, compared to ITNs with only pyrethroid. About 20% of sleepers reported potential side-effects (headache and/or sneezing) from use of ITN treated with carbosulfan alone. Further development of this new 'two-in-one' ITN concept requires a range of investigations (choice of effective products, cost-benefit analysis, safety, etc.) leading to factory production of wash-resistant insecticidal nets treated with complementary insecticides.     

Optimization of pyrethroid and repellent on fabrics against Stegomyia albopicta (=Aedes albopictus) using a microencapsulation technique

A new approach employing a combination of pyrethroid and repellent is proposed to improve the protective efficacy of conventional pyrethroid‐treated fabrics against mosquito vectors. In this context, the insecticidal and repellent efficacies of commonly used pyrethroids and repellents were evaluated by cone tests and arm‐in‐cage tests against Stegomyia albopicta (=Aedes albopictus) (Diptera: Culicidae). At concentrations of LD₅₀ (estimated for pyrethroid) or ED₅₀ (estimated for repellent), respectively, the knock‐down effects of the pyrethroids or repellents were further compared. The results obtained indicated that deltamethrin and DEET were relatively more effective and thus these were selected for further study. Synergistic interaction was observed between deltamethrin and DEET at the ratios of 5 : 1, 2 : 1, 1 : 1 and 1 : 2 (but not 1 : 5). An optimal mixing ratio of 7 : 5 was then microencapsulated and adhered to fabrics using a fixing agent. Fabrics impregnated by microencapsulated mixtures gained extended washing durability compared with those treated with a conventional dipping method. Results indicated that this approach represents a promising method for the future impregnation of bednet, curtain and combat uniform materials.     

Characterization of the voltage‐gated sodium channel of the Asian citrus psyllid,Diaphorina citri

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is an important insect pest of citrus. It is the vector of ‘Candidatus’ Liberibacter asiaticus, a phloem‐limited bacterium that infects citrus, resulting in the disease Huanglongbing (HLB). Disease management relies heavily on suppression of D. citri populations with insecticides, including pyrethroids. In recent annual surveys to monitor insecticide resistance, reduced susceptibility to fenpropathrin was identified in several field populations of D. citri. The primary target of pyrethroids is the voltage‐gated sodium channel (VGSC). The VGSC is prone to target‐site insensitivity because of mutations that either reduce pyrethroid binding and/or alter gating kinetics. These mutations, known as knockdown resistance or kdr, have been reported in a wide diversity of arthropod species. Alternative splicing, in combination with kdr mutations, has been also associated with reduced pyrethroid efficacy. Here we report the molecular characterization of the VGSC in D. citri along with a survey of alternative splicing across developmental stages of this species. Previous studies demonstrated that D. citri has an exquisite enzymatic arsenal to detoxify insecticides resulting in reduced efficacy. The results from the current investigation demonstrate that target‐site insensitivity is also a potential basis for insecticide resistance to pyrethroids in D. citri. The VGSC sequence and its molecular characterization should facilitate early elucidation of the underlying cause of an established case of resistance to pyrethroids. This is the first characterization of a VGSC from a hemipteran to this level of detail, with the majority of the previous studies on dipterans and lepidopterans.     

Impact of Insecticide Resistance on the Effectiveness of Pyrethroid-Based Malaria Vectors Control Tools in Benin: Decreased Toxicity and Repellent Effect

Since the first evidence of pyrethroids resistance in 1999 in Benin, mutations have rapidly increased in mosquitoes and it is now difficult to design a study including a control area where malaria vectors are fully susceptible. Few studies have assessed the after effect of resistance on the success of pyrethroid based prevention methods in mosquito populations. We therefore assessed the impact of resistance on the effectiveness of pyrethroids based indoor residual spraying (IRS) in semi-field conditions and long lasting insecticidal nets (LLINs) in laboratory conditions. The results observed showed low repulsion and low toxicity of pyrethroids compounds in the test populations. The toxicity of pyrethroids used in IRS was significantly low with An. gambiae s.l (< 46%) but high for other predominant species such as Mansonia africana (93% to 97%). There were significant differences in terms of the repellent effect expressed as exophily and deterrence compared to the untreated huts (P<0.001). Furthermore, mortality was 23.71% for OlyseNet® and 39.06% for PermaNet®. However, with laboratory susceptible “Kisumu”, mortality was 100% for both nets suggesting a resistance within the wild mosquito populations. Thus treatment with pyrethroids at World Health Organization recommended dose will not be effective at reducing malaria in the coming years. Therefore it is necessary to study how insecticide resistance decreases the efficacy of particular pyrethroids used in pyrethroid-based vector control so that a targeted approach can be adopted.     

Longitudinal follow‐up of malaria transmission dynamics in two villages in a Sahelian area of Niger during a nationwide insecticide‐treated bednet distribution programme

Malaria transmission was monitored in two villages in the Sahel zone of Niger over 4 years. During this period, a nationwide vector control programme was carried out in which insecticide‐treated bednets were distributed free to mothers of children aged <5 years. Anopheles gambiae and Anopheles arabiensis (Diptera: Culicidae) were found to be the major malaria vectors. The dynamics of An. gambiae s.l. did not vary dramatically over the study period although the proportion of female mosquitoes found resting indoors decreased in both villages and, in one village, the parity rate and sporozoite index were significantly reduced after bednet distribution. By contrast with An. gambiae, the dynamics of Anopheles funestus altered greatly after the bednet distribution period, when adult density, endophagous rate and sporozoite rates decreased dramatically. Our observations highlight the importance of quantifying and monitoring the dynamics and infections of malaria vectors during large‐scale vector control interventions.     

Susceptibility status of the wild-caught Phlebotomus argentipes (Diptera: Psychodidae: Phlebotominae), the sand fly vector of visceral leishmaniasis,to different insecticides in Nepal

BackgroundVisceral leishmaniasis (VL) is targeted for elimination as a public health problem in Nepal by 2023. For nearly three decades, the core vector control intervention in Nepal has been indoor residual spraying (IRS) with pyrethroids. Considering the long-term use of pyrethroids and the possible development of resistance in the vector Phlebotomus argentipes sand flies, we monitored the susceptibility status of their field populations to the insecticides of different classes, in villages with and without IRS activities in recent years.Methodology/Principal findingsSand flies were collected from villages with and without IRS in five VL endemic districts from August 2019 to November 2020. The WHO susceptibility test procedure was adopted using filter papers impregnated at the discriminating concentrations of insecticides of the following classes: pyrethroids (alpha-cypermethrin 0.05%, deltamethrin 0.05%, and lambda-cyhalothrin 0.05%), carbamates (bendiocarb 0.1%) and organophosphates (malathion 5%). Pyrethroid resistance intensity bioassays with papers impregnated with 5× of the discriminating concentrations, piperonyl butoxide (PBO) synergist-pyrethroid bioassays, and DDT cross-resistance bioassays were also performed. In the IRS villages, the vector sand flies were resistant (mortality rate <90%) to alpha-cypermethrin and possibly resistant (mortality rate 90–97%) to deltamethrin and lambda-cyhalothrin, while susceptibility to these insecticides was variable in the non-IRS villages. The vector was fully susceptible to bendiocarb and malathion in all villages. A delayed knockdown time (KDT₅₀) with pyrethroids was observed in all villages. The pyrethroid resistance intensity was low, and the susceptibility improved at 5× of the discriminating concentrations. Enhanced pyrethroid susceptibility after pre-exposure to PBO and the DDT-pyrethroid cross-resistance were evident.Conclusions/SignificanceOur investigation showed that P. argentipes sand flies have emerged with pyrethroid resistance, suggesting the need to switch to alternative classes of insecticides such as organophosphates for IRS. We strongly recommend the regular and systematic monitoring of insecticide resistance in sand flies to optimize the efficiency of vector control interventions to sustain VL elimination efforts in Nepal.     

Impact of environment on mosquito response to pyrethroid insecticides: Facts,evidences and prospects

By transmitting major human diseases such as malaria, dengue fever and filariasis, mosquito species represent a serious threat worldwide in terms of public health, and pose a significant economic burden for the African continent and developing tropical regions. Most vector control programmes aiming at controlling life-threatening mosquitoes rely on the use of chemical insecticides, mainly belonging to the pyrethroid class. However, resistance of mosquito populations to pyrethroids is increasing at a dramatic rate, threatening the efficacy of control programmes throughout insecticide-treated areas, where mosquito-borne diseases are still prevalent. In the absence of new insecticides and efficient alternative vector control methods, resistance management strategies are therefore critical, but these require a deep understanding of adaptive mechanisms underlying resistance. Although insecticide resistance mechanisms are intensively studied in mosquitoes, such adaptation is often considered as the unique result of the selection pressure caused by insecticides used for vector control. Indeed, additional environmental parameters, such as insecticides/pesticides usage in agriculture, the presence of anthropogenic or natural xenobiotics, and biotic interactions between vectors and other organisms, may affect both the overall mosquito responses to pyrethroids and the selection of resistance mechanisms. In this context, the present work aims at updating current knowledge on pyrethroid resistance mechanisms in mosquitoes and compiling available data, often from different research fields, on the impact of the environment on mosquito response to pyrethroids. Key environmental factors, such as the presence of urban or agricultural pollutants and biotic interactions between mosquitoes and their microbiome are discussed, and research perspectives to fill in knowledge gaps are suggested.     

Chronology of sodium channel mutations associated with pyrethroid resistance in Aedes aegypti

Aedes aegypti is the primary mosquito vector of dengue, yellow fever, Zika and chikungunya. Current strategies to control Ae. aegypti rely heavily on insecticide interventions. Pyrethroids are a major class of insecticides used for mosquito control because of their fast acting, highly insecticidal activities and low mammalian toxicity. However, Ae. aegypti populations around the world have begun to develop resistance to pyrethroids. So far, more than a dozen mutations in the sodium channel gene have been reported to be associated with pyrethroid resistance in Ae. aegypti. Co-occurrence of resistance-associated mutations is common in pyrethroid-resistant Ae. aegypti populations. As global use of pyrethroids in mosquito control continues, new pyrethroid-resistant mutations keep emerging. In this microreview, we compile pyrethroid resistance-associated mutations in Ae. aegypti in a chronological order, as they were reported, and summarize findings from functional evaluation of these mutations in an in vitro sodium channel expression system. We hope that the information will be useful for tracing possible evolution of pyrethroid resistance in this important human disease vector, in addition to the development of methods for global monitoring and management of pyrethroid resistance in Ae. aegypti.     

Development of Resistance to Pyrethroid in Culex pipiens pallens Population under Different Insecticide Selection Pressures

Current vector control programs are largely dependent on pyrethroids, which are the most commonly used and only insecticides recommended by the World Health Organization for insecticide-treated nets (ITNs). However, the rapid spread of pyrethroid resistance worldwide compromises the effectiveness of control programs and threatens public health. Since few new insecticide classes for vector control are anticipated, limiting the development of resistance is crucial for prolonging efficacy of pyrethroids. In this study, we exposed a field-collected population of Culex pipiens pallens to different insecticide selection intensities to dynamically monitor the development of resistance. Moreover, we detected kdr mutations and three detoxification enzyme activities in order to explore the evolutionary mechanism of pyrethroid resistance. Our results revealed that the level of pyrethroid resistance was proportional to the insecticide selection pressure. The kdr and metabolic resistance both contributed to pyrethroid resistance in the Cx. pipiens pallens populations, but they had different roles under different selection pressures. We have provided important evidence for better understanding of the development and mechanisms of pyrethroid resistance which may guide future insecticide use and vector management in order to avoid or delay resistance.