Pyrethroid Insecticide Resistance <i>kdr</i>Gene in the House Fly, <i>Musca domestica</i>(Diptera: Muscidae), in the United Arab Emirates

The house fly, Musca domestica L., is a very important insect because of its role as a vector of several human, livestock, and poultry diseases. Different groups of insecticides, including the pyrethroids, are used to control house flies. The objective of the current study was to conduct a survey of the kdr insecticide resistance gene in the house fly population in the United Arab Emirates (UAE). Flies were collected from five locations (Abu Dhabi, Dubai, Fujairah, Ajman, and Ras Al- Khaymah). Genomic DNA was extracted and polymerase chain reaction (PCR) amplification of specific allele (PASA) was performed. The maximum percentage (70%) of homozygous genotype (kdr/kdr) occurred at Ajman, followed by Dubai (59.5%), and the minimum percentage occurred at Ras Al-Khaymah (14.3%). Resistant insects of the genotype kdr/kdr were detected in all of the tested house fly populations. Ajman and Fujairah house fly populations were in Hardy-Weinberg equilibrium. The resistance kdr allele was found at a high frequency (0.54 - 0.8) at all locations except at Ras Al-Khaymah (0.21). Together, this study demonstrated that the pyrethroid insecticide resistance kdr allele was found in UAE house fly populations, strongly suggesting that a countrywide pyrethroid insecticide resistance management program needs to be implemented.

Kdr等位基因频率与家蝇对溴氰菊酯抗性的关系

根据家蝇拟除虫菊酯kdr (knockdownresistance)抗性的遗传标记L10 14F突变 ,设计竞争特异性等位基因PCR扩增方法 (cPASA ,competitivePCRamplificationofspecificallele) ,用于检测单头家蝇基因组中的kdr点突变。通过对 1个实验室敏感种群及 8个野外种群共 4 5 0个个体的kdr等位基因型检测 ,结果表明kdr等位基因频率与溴氰菊酯LD50 值之间有线性正相关回归关系 (Γyx =0 913,P =0 0 0 0 6 )。遗传学分析表明各种群kdr等位基因频率处于Hardy Weinberg平衡状态 ,遗传差异的无偏估计值表明 。

淡色库蚊(Culexpipienspallens)与击倒抗性(kdr)相关的钠通道基因突变

本研究采用RT -PCR技术,使用简并引物分别从淡色库蚊(Culexpipienspallens)敏感品系和抗溴氰菊酯品系中扩增出钠通道ⅡS4～ⅡS6区域的基因片段,长度为35 9bp。该基因片段所编码的氨基酸与黑尾果蝇(Drosophilamelanogaster)、家蝇(Muscadomestica)、埃及伊蚊(Aedesaegypti)、冈比亚按蚊(Anophelesgambiae)及德国小蠊(Blattellagermanica)等昆虫相应区域的氨基酸序列具有较高的同源性,其同源性分别为95. 8% ,95. 0 % ,10 0 . 0 % ,98 .3%和95 . 0 %。经序列比对,确认抗溴氰菊酯品系淡色库蚊钠通道基因在10 14位点发生了突变:该位点的碱基“A”突变为“T”,其对应氨基酸由亮氨酸(L)变为苯丙氨酸(F) ,该突变(L10 14F型)在多种昆虫中较为常见。

中华按蚊对菊酯类杀虫剂的抗性及kdr突变

目的了解江苏省洪泽湖地区疟疾媒介中华按蚊对菊酯类杀虫剂的抗性状况及钠离子通道部分位点突变情况。方法 2012-2013年8-9月,沿洪泽湖周边采集淮安、洪泽、泗洪、盱眙、泗阳等地区中华按蚊成蚊样本,圆球法检测击倒中时间(KT50)。多重PCR法检测钠离子通道1014位点kdr基因突变情况。结果 5个地区采集的按蚊均为中华按蚊,中华按蚊成蚊对氯菊酯、高效氯氰菊酯、溴氰菊酯3种杀虫剂的平均KT50分别为16.92、16.53、22.98 min,抗性倍数为4.61、5.45和4.60,均为抗性种群。部分kdr基因发生突变,存在L1014C和L1014F两种突变类型,7种基因型(TTG/TTG,TTG/TTT,TTG/TTC,TTG/TTG,TTT/TTT,TTT/TTC,TGT/TGT)主要突变类型为TTT(或TTC),突变频率为72%~87%,其次为TGT突变12%~21%,敏感的TTG较少。结论该地区中华按蚊对3种菊酯类杀虫剂产生一定的抗性,钠离子通道kdr基因L1014位点出现高频率的突变,突变类型主要为TTT和TGT,提示该地区中华按蚊成蚊防治需根据抗性监测结果加强抗性治理。

不同杀虫剂选育对家蝇抗药性水平及kdr基因频率的影响

采用杀虫剂（溴氰菊酯和甲基嘧啶磷）筛选及不接触药物自然衰退的方法，研究了家蝇Musca domestica氯氟氰菊酯高抗品系（Cyh—R）对杀虫剂的抗性变化，探讨蝇类抗药性治理的方法。用点滴法测定氯氟氰菊酯对不同家蝇品系的毒力，比较抗药性的变化，结合特异性等位基因PCR扩增（PASA）技术检测了不同家蝇品系的kdr基因频率，探讨kdr基因频率与抗性水平之间的关系。结果表明：甲基嘧啶磷筛选后，氯氟氰菊酯对第2～8代Cyh—R品系的LD50呈递减趋势，从F0的2．8434μg／蝇降为F8的0．4404μg／蝇，但第8—18代Cyh—R品系的LD5u呈逐代递增趋势；溴氰菊酯筛选后，氯氟氰菊酯对Cyh—R品系第2～16代的LD50呈上升趋势，从F0的2．8434μg／蝇升至F16的24．3249μg／蝇；表明了施用有机磷杀虫剂可降低其对氯氟氰菊酯的抗药性，而施用拟除虫菊酯药剂则有助于其对氯氟氰菊酯抗药性的增长；不使用任何杀虫剂也能降低其对氯氟氰菊酯的抗药性，但下降速率低于甲基嘧啶磷。PASA技术检测表明Cyh—R品系的kdr抗性基因频率为88．8％，不经过任何药剂筛选其kdr抗性基因频率下降程度最大，达到69．7％；甲基嘧啶磷筛选后其结果降为78．8％，而经溴氰菊酯筛选后kdr抗性基因频率则明显升高，达到98．9％。通过对kdr抗性基因频率和抗性水平进行相关和回归分析表明kdr抗性基因频率与家蝇对氯氟氰菊酯的LD50呈对数关系，即LD50值高的品系其kdr抗性基因频率相应的也较高。建议在家蝇防治中考虑轮换用药。

淡色库蚊kdr等位基因突变及抗药性检测方法的研究

目的了解山东省不同地区的淡色库蚊成蚊对溴氰菊酯的抗药性水平及其kdr等位基因的突变与抗药性水平间的关联情况,并探索建立蚊虫抗药性的现场检测方法。方法采用PCR和AS-PCR技术,使用特异性引物克隆不同地区野生淡色库蚊成蚊kdr基因序列,并进行基因测序。利用线性回归分析判断其突变情况与抗药性的关联情况。结果成功克隆出kdr等位基因,通过基因序列分析发现在淡色库蚊钠通道第II结构域S6节段1014位点上存在2种突变,即L1014F:TTA突变为TTT,相应的亮氨酸(L)被苯丙氨酸(F)取代,L1014S:TTA突变为TCA,相应的亮氨酸(L)被丝氨酸(S)取代。Kdr基因L1014F突变和L1014S突变与淡色库蚊对溴氰菊酯的抗性表型呈正相关。蚊虫抗药性检测的结果显示PCR技术优于AS-PCR技术。结论淡色库蚊kdr基因突变与溴氰菊酯抗药性表型呈正相关,PCR和AS-PCR技术都可以应用于蚊虫抗药性的现场检测。

北京市两个白纹伊蚊种群kdr抗性突变检测分析

目的对2个白纹伊蚊野外种群的kdr抗性突变进行检测分析,评估其对拟除虫菊酯类杀虫剂的抗性风险。方法利用PCR扩增白纹伊蚊钠离子通道基因(voltage-gated sodium channel, VGSC)的两个结构域并进行测序,分析与击倒抗性(knockdown resistance,kdr)有关位点(1 016、1 532和1 534位点)的突变与系统进化关系。结果在2个种群的60只白纹伊蚊中,检测到位点1 016发生突变的有3只,占5.00%;位点1 534发生突变的有2只,占3.33%;位点1 532发生突变的有17只,占28.33%。对应的序列单倍型分析显示种群内kdr突变具有多种进化起源。结论白纹伊蚊野外种群在拟除虫菊酯类杀虫剂选择压力下,其靶标发生了多位点kdr突变,今后伊蚊防治应加强环境治理和蚊幼控制,合理使用拟除虫菊酯类杀虫剂控制成蚊进而延缓抗性产生。

重庆市中华按蚊溴氰菊酯抗性与kdr基因突变的关系

摘要中华按蚊是我国的主要传疟媒介之一。近年来我国不同地区的蚊虫抗药性监测数据显示，多种媒介蚊虫对拟除虫菊酯杀虫剂产生了不同程度的抗药性。为了解重庆市中华按蚊对拟除虫菊酯杀虫剂抗性水平及其与kdr基因突变的关系，我们于2011年7～9月采用WHO标准区分剂量法对重庆市璧山县和秀山县的中华按蚊做了抗药性生物测定，通过测序检测了钠离子通道IIS6节段kdr基因突变。生物测定结果显示璧山县种群死亡率为32．72％，秀山县种群为12．62％，比1992和2001年抗性水平（死亡率分别为80．72％、76．92％）明显提高。测序得到325bp的kdr片段，在L1014位点有‘兀＇．I＇、TGT突变。突变统计显示，璧山县种群基因突变频率为7．23％，秀山县种群为68．60％，两个群体的基因突变与抗药性的关联未达显著水平，表明这两个中华按蚊种群L1014位点的rI’rI＇T和TGT突变与抗药性表型间无关联。中华按蚊抗药性分子机理需要进一步扩大研究种群，检测其他突变位点以及相关代谢酶的活性。

淡色库蚊对拟除虫菊酯抗性与kdr等位基因频率的关系

利用接触筒法检测淡色库蚊6个野外种群成蚊对溴氰菊酯、高效氯氰菊酯和氯菊酯的抗性水平,同时利用PASA(PCR amplification of specific alleles)方法检测每个种群kdr等位基因的频率。结果表明:不同种群的溴氰菊酯抗性水平与抗性等位基因频率有显著的相关性(R2=0.836,P=0.011),但高效氯氰菊酯和氯菊酯抗性水平与抗性等位基因频率无显著的相关性(R2分别为0.493和0.530,P值分别为0.120和0.101);对3种拟除虫菊酯抗性平均值直线回归分析显示,抗性等位基因频率与生物测试结果呈显著直线相关(R2=0.840,P=0.010)。

kdr突变和解毒代谢在B型烟粉虱对高效氯氰菊酯抗性中的作用

本研究明确了kdr突变和解毒代谢在B型烟粉虱Bemisia tabaci对高效氯氰菊酯抗性中的作用。B型烟粉虱NJ品系相对于烟粉虱敏感品系(SUD-S,非B型)对高效氯氰菊酯有266倍的抗性。对NJ品系用高效氯氰菊酯进行群体筛选获得抗性为811倍的NJ-R1品系,对NJ品系进行单对交配筛选获得抗性达2634倍的NJ-R2品系。在NJ,NJ-R1和NJ-R2品系间,酯酶、多功能氧化酶和谷胱甘肽S-转移酶活性无显著差异,说明在筛选过程中解毒代谢没有发生变化。PASA检测结果表明,NJ-R2品系钠离子通道基因L925I突变(kdr突变)频率为100%,NJ-R1品系为80.6%,NJ品系为55%。由此可见,kdr突变频率的增加是B型烟粉虱种群对高效氯氰菊酯抗性上升的主要原因。在NJ,NJ-R1和NJ-R2品系中,增效醚(PBO)对高效氯氰菊酯的增效作用均为20倍左右,而PBO对SUD-S品系没有任何增效作用。PBO能同时抑制烟粉虱的多功能氧化酶和酯酶,通过与TPP增效作用进行对比表明,在B型烟粉虱中PBO所产生的增效作用主要来源于对酯酶的抑制。因此,B型烟粉虱品系(NJ-R2,NJ-R1和NJ)与非B型SUD-S品系相比存在20倍左右的先天抗性,该先天抗性主要与B型烟粉虱的特有酯酶有关。在B型烟粉虱品系对高效氯氰菊酯的抗性中,抗性水平完全由kdr突变频率高低所决定。

山东省济宁市白纹伊蚊对溴氰菊酯抗性与kdr等位基因突变观察

目的了解山东省济宁市白纹伊蚊现场群体对溴氰菊酯的抗药性,并检测击倒抗性(kdr)等位基因突变情况,为kdr突变作为杀虫剂抗性检测的生物标记提供理论依据。方法WHO成蚊接触筒法测定白纹伊蚊对溴氰菊酯的抗性,PCR扩增电压门控钠离子通道(VGSC)基因部分片段,测序后检测kdr等位基因突变情况。结果WHO成蚊接触筒检测济宁白纹伊蚊雌蚊死亡率为44.58%,在VGSC基因1534氨基酸位点检测到3种等位基因类型:野生型TTC(F1534)(71.43%)和突变型TCC(F1534S)(13.69%)、TTG(F1534L)(14.88%);检测到5种等位基因型:野生型纯合子TTC/TTC,突变型纯合子TCC/TCC、TTG/TTG,以及野生/突变型杂合子TTC/TTG、TTC/TCC。结论济宁市白纹伊蚊对溴氰菊酯已产生抗药性,并监测到其1534氨基酸位点上存在2种kdr等位基因点突变,可能与杀虫剂的长期选择压力有关。

Evidence of increasing L1014F kdr mutation frequency in Anopheles gambiae s.l.pyrethroid resistant following a nationwide distribution of LLINs by the Beninese National Malaria Control Programme

Objective:To determine the susceptibility status to pyrethroid in Anopheles gambiae s.l.(An.gambiae),the distribution of kdr"Leu-Phe"mutation in malaria vectors in Benin and to compare the current frequency of kdr"Leu-Phe"mutation to the previous frequency after long-lasting insecticide treated nets implementation.Methods:Larvae and pupae of An.gambiae s.l.mosquitoes were collected from the breeding sites in Littoral,Zou.Borgou and Alibori provinces.CDC susceptibility tests were conducted on unfed females mosquitoes aged 2-5 d old.An.gambiae mosquitoes were identified to species using PCR techniques.Molecular assays were also carried out to identify kdr mutations in individual mosquitoes.Results:The results showed that An.gambiae Malanville and Suru-lere populations were resistant to deltamethrin.Regarding An.gambiae Parakou and Bohicon populations,they were resistant to permethrin.PCR revealed 100%of mosquitoes tested were An.gambiae s.s.The L1014F kdr mutation was found in An.gambiae s.s.Malanville and Parakou at various allelic frequencies.The increase of kdr allelic frequency was positively correlated with CDC bioassays data.Conclusions:Pyrethroid resistance is widespread in malaria vector in Benin and kdr mutation is the main resistance mechanism involved.More attention may be paid for the future success of malaria control programmes based on LLINs with pyrethroids in the country.

新疆与华北棉区棉铃虫对氯氟氰菊酯kdr型抗性频率比较

通过单对杂交结合热探针法 ,研究比较了新疆与华北棉区田间种群棉铃虫对氯氟氰菊酯 kdr型抗性个体频率、抗性基因型频率和抗性基因频率的差异。结果表明 :新疆种群、河北冀州种群和河南西华种群的 kdr型抗性个体频率分别为 1.0 0 %、2 8.4 3%、2 4 .4 3% ;新疆XF1种群、冀州 JF1、JF2 种群的 kdr型抗性基因频率分别为 0、2 0 .83%、11.11%。分别从群体与个体水平上说明了新疆棉铃虫对菊酯类农药尚处于敏感阶段 ,而华北种群 kdr型抗性已达较高水平 ,并且抗性个体主要以杂合子形式存在。

Insecticide resistance status and biochemical mechanisms involved in Aedes mosquitoes: A scoping review

Mosquitoes belonging to the genus Aedes pose a significant threat to human health on a global scenario due to their role in transmission of dengue,chikungunya,zika,and yellow fever.In absence of specific medications and vaccines against these diseases,disease prevention relies on vector control.However,in today’s world,vector control is facing major challenges due to the onset of insecticide resistance in mosquitoes.There are four main mechanisms of insecticide resistance,namely,behavioral resistance,reduced penetration/cuticular resistance,metabolic detoxification,and target site resistance;however,the latter two mechanisms have been studied widely in Aedes mosquitoes.Insecticide resistance in Aedes mosquitoes is widespread throughout the world.This review compiles the degree of insecticide resistance/susceptibility prevailing among different field populations of Aedes mosquitoes worldwide.In addition,the review has detailed the mechanisms providing the resistance phenomenon observed in nature in Aedes mosquitoes.

济宁市白纹伊蚊kdr基因突变检测

目的 调查济宁市白纹伊蚊对常用杀虫剂溴氰菊酯的抗性表型及击倒抗性相关基因改变。方法 使用世界卫生组织(WHO)标准成蚊接触筒法检测白纹伊蚊成蚊对溴氰菊酯的抗药性。PCR检测kdr基因1 532和1 534位点的突变情况。结果 在电压门控钠离子通道Vgsc基因中发现了I1 532T,F1 534L和F1 534S突变。I1 532T突变等位基因均出现在抗性蚊虫中。相关性研究显示F1 534S突变与溴氰菊酯抗药性表型呈正相关。结论 山东省济宁市蚊虫抗药性水平较高,需要定期进行蚊虫抗药性监测和风险评估。

First investigation of deltamethrin pyrethroid susceptibility and resistance status of Anopheles labranchiae(Falleroni, 1926), potential malaria vector in Tunisia

Objective: To evaluate the deltamethrin pyrethroid insecticides against Anopheles labranchiae, potential malaria vector in Tunisia.Methods: Six field populations of Anopheles labranchiae mosquitoes were collected from six localities in Northern and Central Tunisia between October and November 2016.Different bioassays were performed to estimate the level of resistance in each collected population. Two synergists were used to estimate the involvement of detoxification enzymes in insecticide resistance.Results: All studied strains were resistant and the RR50 ranged from 12.5 in sample #1 to72.5 in sample #6. Synergist tests using piperonyl butoxide indicated the involvement of monoxygenases enzymes in the recorded resistance. In contrast, the increase of deltamethrin mortality was not significant in presence of S,S,sributyl phosphorothioate(0.8 < SR < 1.2), suggesting no role of esterases(and/or GST) in the resistance phenotype. The correlation recorded between mortality due to DDT and the LC50 of deltamethrin insecticide indicated an insensitive sodium channel affected by Kdr mutation(Spearman rank correlation, r =-0.59, P < 0.01).Conclusions: These results should be considered in the current mosquitoes control programs in Tunisia. The use of pesticides and insecticides by both agricultural and public health departments in Tunisia should be more rational to reduce the development of resistance in populations. Different insecticide applications should be implemented alternately.

臭虫击倒抗性基因突变检测及抗性测定

近20多年,臭虫(Cimex spp.)在世界范围内成为常见的卫生害虫,其防治主要采用化学防治,但很多种群发现击倒抗性(Knockdown resistance gene,kdr)基因突变的存在以及抗药性。监测kdr的发生频率以及不同种群对农药的抗性对臭虫有效防治很重要,但我国对臭虫种群的抗药性报道很少。本试验采用点滴法测定了1个温带臭虫Cimex lectularius野外种群对氯虫苯甲酰胺、呋虫胺、吡虫啉、噻虫嗪和高效氯氰菊酯等5种药剂的毒性及抗性水平,使用区分剂量快速鉴定抗性方法对2个温带臭虫和2个热带臭虫Cimex hemipterus种群对高效氯氰菊酯的抗性水平进行了检测,此外用PCR方法检测8个臭虫地理种群(1个温带臭虫实验室种群,1个温带臭虫野外种群和6个热带臭虫野外种群)174个个体的kdr突变频率。点滴法结果表明,5种杀虫剂对温带臭虫的毒性是吡虫啉和呋虫胺>噻虫嗪>氯虫苯甲酰胺和高效氯氰菊酯,测试的野外温带臭虫种群仅对噻虫嗪无明显抗性。热带臭虫2个野外种群对高效氯氰菊酯的抗性均远高于温带臭虫。在温带臭虫的实验室种群中未检测到突变,在野外种群中检测到了V419L和L925I突变,可分为2种基因型类型(A:无突变位点;B:同时有L925I和V419L),而在热带臭虫的6个种群检测到M918I和L1014F突变,只有1种基因型类型,即M918I和L1014F双位点突变。温带臭虫1个野外种群及热带臭虫6个野外种群kdr突变的存在与臭虫对高效氯氰菊酯敏感密切关联。基于kdr基因突变检测结果推测我国臭虫种群广泛存在对拟除虫菊酯的抗性。

Correlation between adult pyrethroid resistance and knockdown resistance(kdr)mutations in Aedes albopictus(Diptera:Culicidae)field populations in China

Background:Arboviral disease transmitted by Aedes albopictus such as dengue fever is an important threat to human health.Pyrethroid resistance raises a great challenge for mosquito control.A systematic assessment of Ae.albopictus resistance status in China is urgently needed,and the study of correlation between pyrethroid resistance and knockdown resistance(kdr)mutations would provide information to guide the control of the Ae.albopictus vector.Methods:Five field populations of Ae.albopictus were collected from Jinan(JN),Hangzhou(HZ),Baoshan(BS),Yangpu(YP)and Haikou(HK),China in 2017.Insecticide-impregnated papers were prepared with four pyrethroid chemicals,deltamethrin,permethrin,beta-cypermethrin and lambda-cyhalothrin.The susceptibility of Ae.albopictus to pyrethroids was tested by the WHO tube assay.Kdr mutations were identified by PCR and sequencing.Moreover,the correlation analysis between kdr alleles and pyrethroid resistance was performed.Results:All five populations of Ae.albopictus showed resistance to four pyrethroid insecticides.One kdr mutant allele at codon 1532 and three at 1534 were detected with frequency of 5.33%(I1532T),44.20%(F1534S),1.83%(F1534 L)and 0.87%(F1534C),respectively.Both 1532 and 1534 mutation mosquitoes were found in the BS and YP populations.Allele I1532T was negatively correlated with deltamethrin resistance phenotype(OR<1),while F1534S mutation was positively correlated with deltamethrin and permethrin resistance(OR>1).Conclusions:The five field populations of Ae.albopictus adults were all resistant to deltamethrin,permethrin,betacypermethrin and lambda-cyhalothrin.Mutant F1534S was clearly associated with pyrethroid resistance phenotype in Ae.albopictus and this could be developed as a molecular marker to monitor the pyrethroid resistance problem in China.

Genetic structure of Aedes albopictus(Diptera:Culicidae)populations in China and relationship with the knockdown resistance mutations

Background Mosquito control is needed to prevent dengue fever, which is mainly spread byAedes albopictus in China. Application of insecticides is one of the main mosquito control methods;however, this approach can fail due to the knockdown resistance (kdr) gene mutation that causes decreased sensitivity to insecticides inAe. albopictus. Thekdr mutation patterns among different regions in China differ significantly. However, the underlying mechanism and factors that influencekdr mutation remain unclear. To explore the potential influence of genetic background on the development of insecticide resistance inAe. albopictus, we analyzed the genetic structure ofAe. albopictus populations in China and its correlation with majorkdr mutations.Methods We collectedAe. albopictus from 17 sites in 11 provinces (municipalities) across China from 2016 to 2021 and extracted the genomic DNA from individual adult mosquitoes. We selected eight microsatellite loci for genotyping, and based on microsatellite scores, we estimated intraspecific genetic diversity, population structure, and effective population size. The association between the intrapopulation genetic variation and F1534 mutation rate was evaluated by the Pearson correlation coefficient.Results Based on variation analysis of the microsatellite loci of 453 mosquitoes representing 17 populations throughout China, more than 90% of the variation occurred within individuals, whereas only about 9% of the variation occurred among populations, indicating that field populations ofAe. albopictus are highly polymorphic. The northern populations tended to belong to gene pool I (BJFT 60.4%, SXXA 58.4%, SDJN 56.1%, SXYC 46.8%), the eastern populations tended to belong to pool III (SH 49.5%, JZHZ 48.1%), and the southern populations tended to belong to three different gene pools. Moreover, we observed that the greater the fixation index (FST), the lower the wild-type frequency of F1534 ofVSGC.Conclusions The degree of genetic differentiation amongAe. albopictus populations in China was low. These populations were divided into three gene pools, in which the northern and eastern pools are relatively homogeneous, while the southern gene pool is heterogeneous. The possible correlation between its genetic variations andkdr mutations is also noteworthy.

海南省白纹伊蚊抗药性及抗性相关kdr和ace-1基因突变调查

目的了解海南省白纹伊蚊对常用杀虫剂抗性水平及其击倒抗性(knockdown resistance,kdr)和乙酰胆碱酯酶1(acetylcholnesterase number one,ace-1)基因的突变情况。方法分别于2020年和2021年在海南省儋州、三亚、琼中、琼海、昌江和万宁采集白纹伊蚊幼虫,测定其对常用杀虫剂的抗药性,抽取抗性测定存活样品并对其kdr基因和ace-1基因的突变进行检测。结果海南不同地区白纹伊蚊种群成蚊接触溴氰菊酯(0.03%)、氯菊酯(0.40%)、高效氯氰菊酯(0.40%)、高效氯氰菊酯(0.08%)和高效氯氟氰菊酯(0.07%)药膜24 h后的死亡率分别为5.56%~83.33%、29.89%~92.22%、26.67%~97.78%、11.11%~88.89%和40.00%~83.33%;接触残杀威(0.05%)、噁虫威(0.20%)、马拉硫磷(0.50%)、杀螟硫磷(0.20%)、毒死蜱(2.00%)5种杀虫剂药膜24 h后死亡率为94.89%~100.00%,其中昌江白纹伊蚊种群接触残杀威的死亡率为97.78%,三亚、万宁和琼海白纹伊蚊种群接触马拉硫磷的死亡率分别为94.89%、96.67%和96.67%,三亚和琼海白纹伊蚊种群接触杀螟硫磷的死亡率均为97.78%,其他种群死亡率均为100.00%。聚合酶链式反应产物测序结果显示kdr基因仅1534位点存在突变,共有4种等位基因,即野生型TTC/F和突变型TGT(TGC)/C、TCC/S、TTG/L,其突变频率分别为40.47%,22.25%、36.44%和0.85%,这些突变共组成7种类型,即野生型纯合子F/F,野生型/突变型杂合子F/C、F/S和F/L,突变型杂合子S/C,突变纯合子C/C和S/S,其突变频率依次为19.92%、6.78%、32.63%、1.69%、11.44%、13.14%和14.41%。在ace-1基因对应的119位点未检测到相关氨基酸突变。结论海南省6个地区白纹伊蚊对拟除虫菊酯类的溴氰菊酯、氯菊酯、高效氯氰菊酯和高效氯氟氰菊酯均产生较高抗性,而对氨基甲酸酯类和有机磷类杀虫剂敏感或产生可能抗性;抗性基因突变主要以kdr基因1534位点为主,其突变频率可能是导致海南地区白纹伊蚊产生抗药性的重要原因。