几种杀虫剂对西花蓟马的室内毒力

用浸渍法进行了7种杀虫剂对西花蓟马成虫和若虫的室内毒力测定。结果表明,多杀霉素(48 h)、甲氨基阿维菌素苯甲酸盐(48 h)、阿维菌素(48 h)、辛硫磷(24 h)对西花蓟马成虫的LC50值为0.0544-3.1573 mg.L-1,对西花蓟马若虫的LC50值为0.0219-1.0905 mg.L-1,是防治西花蓟马的较好药剂。     

西花蓟马抗辛硫磷种群的抗性机制及交互抗性

为明确西花蓟马对辛硫磷的抗性风险,研究了西花蓟马抗辛硫磷种群对其他杀虫剂的交互抗性及其对辛硫磷的抗性机制.交互抗性测定结果表明,西花蓟马抗辛硫磷种群对辛硫磷与毒死蜱、高效氯氟氰菊酯和灭多威存在中等水平的交互抗性,对溴虫腈、吡虫啉、甲维盐和多杀菌素存在低水平交互抗性,对啶虫脒和阿维菌素不存在交互抗性.酶抑制剂与辛硫磷的增效剂测定结果表明,胡椒基丁醚(PBO)、三丁基三硫磷酸酯(DEF)和磷酸三苯酯(TPP)对西花蓟马抗辛硫磷种群(XK)、田间种群(BJ)和敏感种群(S)均起到了显著的增效作用(P＜0.05),马来酸二乙酯对西花蓟马抗辛硫磷种群和敏感种群增效作用均不显著,但对田间种群增效作用显著(P＜0.05).生化测定发现:除田间种群西花蓟马乙酰胆碱酯酶活性提高不显著外,西花蓟马抗辛硫磷种群和田间种群的细胞色素P450含量(2.79和1.48倍)、细胞色素b5含量(2.88和1.88倍)及O-脱甲基酶活性(2.60和1.68倍)、羧酸酯酶活性(2.02和1.61倍)和乙酰胆碱酯酶活性(3.10倍)均显著高于敏感种群(P＜0.05);谷胱甘肽-S-转移酶酶活性也有一定程度提高(1.11和1.20倍),但不显著(P＞0.05).表明其体内解毒代谢酶和靶标酶活性提高是西花蓟马对辛硫磷产生抗性的重要原因.     

西花蓟马与烟蓟马生物学特性的比较研究

本试验研究并比较了外来入侵物种西花蓟马Frankliniella occidentalis(Pergande)与本地物种烟蓟马Thrips tabaci Lindeman的生物学特性,包括种群增长速度、发育历期、成虫寿命、孤雌生殖方式下的产卵量以及产卵规律等几个方面。结果显示,当以相同的数量在紫甘蓝上饲养时,只经过3代,烟蓟马的种群数量就可以达到西花蓟马的3倍,随后对2种蓟马种群的性别比进行了鉴定后发现,西花蓟马种群的雌雄比为2.8∶1,而烟蓟马种群中的所有个体均为雌性。除了2龄若虫期和预蛹期之外,烟蓟马在紫甘蓝上的发育历期明显长于西花蓟马,而其雌虫的平均寿命显著短于西花蓟马雌虫,分别是24.94d和43.35d。进行孤雌生殖时,西花蓟马的终生产卵量明显多于烟蓟马,但是在日均产卵量方面,这一情况却相反。     

北京地区西花蓟马田间种群的抗药性监测

采用叶管药膜法在室内测定了2009—2010年北京海淀地区和昌平地区西花蓟马Frankliniella occidentalis(Pergande)田间种群对12种杀虫剂敏感性的年度变化。结果表明,北京昌平和海淀地区的西花蓟马对多数的药剂仍处于敏感状态,但对氯氟氰菊酯已产生近40倍的抗性,昌平种群对多杀菌素具有产生低水平抗性的趋势(抗性倍数为4倍)。推荐药剂包括多杀菌素、阿维菌素、甲氨基阿维菌素苯甲酸盐(甲维盐)、毒死蜱和溴虫腈,应注意与其它药剂的轮换使用,灭多威对西花蓟马的毒力水平最低,不推荐使用。     

5种杀虫剂对西花蓟马和花蓟马的毒力及其生理酶活性的影响

【目的】探究不同杀虫剂对重要入侵害虫西花蓟马及其本地近缘种花蓟马的毒力及对保护酶和解毒酶活性的影响,为进一步研究2种害虫的抗性管理提供依据。【方法】采用浸渍法测定5种田间常用杀虫剂对西花蓟马和花蓟马的毒力,并测定杀虫剂亚致死浓度(LC25)下2种蓟马体内保护酶和解毒酶活性的差异。【结果】不同杀虫剂对2种蓟马的毒力依次为:乙基多杀菌素甲维盐阿维菌素吡虫啉噻虫嗪,乙基多杀菌素对西花蓟马和花蓟马的LC_(50)分别为0.28和0.03 mg·L~(-1)。不同药剂的亚致死剂量(LC_(25))对西花蓟马和花蓟马体内保护酶和解毒酶活性普遍具有诱导作用。其中,阿维菌素对西花蓟马超氧化物歧化酶(SOD)活性诱导作用最强,为326.40 U·mg~(-1),是对照的9.37倍,而乙基多杀菌素对花蓟马SOD活性诱导作用最强,为245.35 U·mg~(-1),是对照的9.32倍;吡虫啉对西花蓟马和花蓟马过氧化物酶(POD)诱导作用最强,分别为298.67和246.79 U·mg~(-1),是对照的37.10和20.57倍;阿维菌素对西花蓟马和花蓟马过氧化氢酶(CAT)和羧酸酯酶(CarE)诱导作用最强,分别为298.67、246.79 U·mg~(-1)(CAT活性)和12.53、11.99 U·mg~(-1)(CarE活性);乙基多杀菌素对西花蓟马和花蓟马谷胱甘肽转移酶(GST)和乙酰胆碱酯酶(AChE)诱导作用最强,分别为77527.59、66927.39 U·mg~(-1)(GST活性)和2.34、2.22 U·mg~(-1)(AChE活性)。【结论】5种杀虫剂中,乙基多杀菌素对2种蓟马的毒力最强;西花蓟马对杀虫剂的解毒代谢能力强于花蓟马。     

不同杀虫剂对西花蓟马的室内毒力及田间药效

【目的】西花蓟马是一种世界性的危险性入侵害虫,筛选防治西花蓟马的有效药剂可为生产中科学用药提供依据。【方法】通过室内毒力测定和田间药效试验,测定了2种化学药剂和8种生物药剂对西花蓟马成虫的致死中浓度(LC_(50))和药后不同时期的防治效果。【结果】室内毒力测定依据LC_(50)值将各药剂对西花蓟马的敏感性由高到低依次排序为乙基多杀菌素(0.1958 mg·L~(-1))、印楝素(0.9399 mg·L~(-1))、苦参碱(1.2483 mg·L~(-1))、阿维菌素(1.8096 mg·L~(-1))、高效氯氰菊酯(4.4458 mg·L~(-1))、藜芦碱(10.7628 mg·L~(-1))、鱼藤酮(18.1898 mg·L~(-1))、吡虫啉(46.3964 mg·L~(-1))、松脂酸钠(131.5214 mg·L~(-1))、苏云金杆菌(446.2318 mg·L~(-1));田间药效试验发现,乙基多杀菌素和吡虫啉防治西花蓟马均表现出较强的速效性和持效性,药后1～14 d的防效分别可达84%和73%以上;其次是藜芦碱,药后1～14 d的防效可达48.15%～61.37%;高效氯氰菊酯的防效较低,药后14 d的防效为46.22%;生物药剂阿维菌素、苏云金杆菌、苦参碱、印楝素的速效性均较低,但防效随施药后时间的延长而逐渐上升;鱼藤酮持效性最低。【结论】乙基多杀菌素和吡虫啉可推荐为生产中防治西花蓟马的首选药剂,植物源药剂藜芦碱和生物药剂阿维菌素可作为交替使用药剂。     

西花蓟马GABA受体基因鉴定及FoRDL 在多杀霉素抗性中的作用

【目的】γ-氨基丁酸(γ-aminobutyric acid, GABA)是动物神经系统中一种重要的神经递质。本研究旨在鉴定西花蓟马Frankliniella occidentalis γ-氨基丁酸受体(GABA receptors, GABAR)家族基因,明确离子型受体(GABA_AR)在西花蓟马对多杀霉素抗性形成中的作用。【方法】根据西花蓟马基因组和转录组数据,鉴定并克隆GABAR基因,进行生物信息学分析;采用qPCR检测GABAAR亚基基因FoRDL, FoLCCH3和FoGRD在西花蓟马多杀霉素敏感品系不同发育阶段(1-2龄若虫、蛹和成虫)的表达模式及在敏感和抗性品系成虫期的相对表达量差异;对西花蓟马敏感品系3日龄成虫的FoRDL进行RNAi 24 h后,在0.250和0.400 mg/L多杀霉素处理下生物测定计算西花蓟马成虫死亡率。【结果】注释并克隆获得8个GABAR基因：FoRDL, FoLCCH3, FoGRD, FoGRD like1, FoGRD-like2, FoB1, FoB2和FoB-like(GenBank登录号: MH148151-MH148158),其ORF长度介于1 080~3 720 bp;系统进化分析表明,西花蓟马的GABAR基因与其他昆虫物种相应基因聚类,具有很高的保守性。GABA_AR亚基FoRDL, FoLCCH3和FoGRD具有典型的N端胞外区环结构(loop A-F)和4个跨膜区(TM 1-4);FoRDL外显子3存在互斥剪切。FoRDL, FoLCCH3和FoGRD的表达量随多杀霉素敏感品系西花蓟马发育阶段逐渐升高,成虫期达最高;FoRDL在西花蓟马抗性品系成虫期的表达量显著低于敏感品系成虫期的。对西花蓟马敏感品系的FoRDL进行RNAi后,在0.250和0.400 mg/L多杀霉素处理剂量下,西花蓟马成虫死亡率均显著下降,分别比对照下降了55.80%和43.00%。【结论】在西花蓟马体内鉴定到5个离子型和3个代谢型GABAR基因,其中FoRDL可能在西花蓟马对多杀霉素产生抗性中发挥一定作用。     

西花蓟马对吡虫啉、辛硫磷和甲维盐的抗性风险和抗性稳定性

为有效控制西花蓟马的危害,采用吡虫啉、辛硫磷和甲维盐药液浸泡芸豆法,分别对西花蓟马敏感种群成虫进行抗性选育,获得抗性种群,应用抗性现实遗传力分析抗性遗传和抗性风险.结果表明:经过32代、32代和24代抗性选育,西花蓟马对吡虫啉、辛硫磷和甲维盐的抗性分别达到13.8、29.4和39.0倍.西花蓟马对吡虫啉、辛硫磷和甲维盐的现实抗性遗传力分别为0.112、0.166和0.259,西花蓟马对甲维盐的抗性上升速度最快,辛硫磷次之,吡虫啉最低.经过药剂筛选后,西花蓟马若虫与成虫对杀虫剂的敏感性差异较敏感种群显著缩小.停止用药剂筛选后继续饲养12代,西花蓟马对吡虫啉、辛硫磷和甲维盐的抗性水平都有一定程度下降,但都没有恢复到敏感性水平.西花蓟马对吡虫啉、辛硫磷和甲维盐具有较高水平抗性的风险,其中对吡虫啉的抗性发展速度相对较慢,且下降速度较快,因此选用吡虫啉防治西花蓟马更合适.     

西花蓟马对多杀菌素的抗性生化机制研究

在室内持续用多杀菌素对西花蓟马Frankliniella occidentalis(Pergande)进行抗性汰选,获得抗性倍数达到11 999倍的极高抗品系。该抗性品系对乙基多杀菌素和噻虫嗪具有显著的交互抗性,抗性倍数分别为53 718和84倍,对阿维菌素和毒死蜱的敏感性也有显著下降,交互抗性倍数分别为3.33和2.28倍,对虫螨腈无明显交互抗性。生化测定结果表明,抗性品系的羧酸酯酶、谷胱甘肽S-转移酶和多功能氧化酶的活力与敏感品系均无显著差异,推测抗性可能与靶标位点的敏感性降低有关。     

西花蓟马抗噻虫胺种群对杀虫剂的交互抗性及机制

噻虫胺是具有内吸和触杀等多种作用方式的新烟碱类杀虫剂,常用于防治入侵害虫西花蓟马。为明确抗性风险,本文研究了西花蓟马抗噻虫胺种群对多种杀虫剂的交互抗性及其机制。经过45代筛选,西花蓟马对噻虫胺产生了高水平抗性(56.8倍)。生物测定结果表明: 西花蓟马高抗噻虫胺种群与噻虫嗪、吡虫啉、毒死蜱、三氟氯氰菊酯、甲维盐存在中等水平交互抗性(18.6>RR₅₀>11.3),对辛硫磷及灭多威具有低水平交互抗性,与溴虫腈和多杀菌素不存在交互抗性。胡椒基丁醚(PBO)与磷酸三苯酯(TPP)对杀灭西花蓟马抗噻虫胺种群(CL)、云南田间种群(YN)和敏感种群(S)均有显著增效作用。西花蓟马抗噻虫胺种群细胞色素P₄₅₀含量(3.6倍)、细胞色素b₅含量(2.9倍)及O-脱甲基酶活性(4.9倍)和羧酸酯酶活性(2.5倍)均显著高于敏感种群,表明多功能氧化酶及羧酸酯酶活性增强是西花蓟马对噻虫胺产生抗性的重要机制。     

Monitoring insecticide resistance in Australian Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) detects fipronil and spinosad resistance

Abstract  Insecticide resistance monitoring using a Potter precision spray tower with discriminating concentration and log dose probability techniques underpins the Australian insecticide management strategy for Frankliniella occidentalis Pergande. Abamectin, acephate, chlorpyrifos, dichlorvos, dimethoate, endosulfan, fipronil, malathion, methamidophos methidathion, methiocarb, methomyl, pyrazophos and spinosad are recommended for use against F. occidentalis but abamectin, methiocarb and pyrazophos are the only chemicals where insecticide resistance has not been detected. Although not registered, chlorfenapyr was effective against F. occidentalis and should be pursued for that purpose. In contrast, chlorpyrifos, dichlorvos and malathion resistance were detected at low to moderate levels throughout the study period putting their sustainable use for F. occidentalis control in doubt . Although it appears that acephate, dimethoate, endosulfan, fipronil, methamidophos, methidathion and spinosad remain effective, some populations contained a small percentage of thrips that survived exposure to a concentration that killed 100% of the susceptible strain. Subsequent laboratory selection of one such population separately with fipronil and spinosad caused an increase in resistance to these insecticides. These products must now be considered at risk. This is the first report of fipronil or spinosad resistance in populations of F. occidentalis.     

Acute toxicities and sublethal effects of some conventional insecticides on Trichogramma chilonis (Hymenoptera: Trichogrammatidae)

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.     

Stability of spinosad resistance in Frankliniella occidentalis (Pergande) under laboratory conditions

The stability of spinosad resistance in western flower thrips (WFT), Frankliniella occidentalis (Pergande), populations with differing initial frequencies of resistance was studied in laboratory conditions. The stability of resistance was assessed in bimonthly residual bioassays in five populations with initial frequencies of 100, 75, 50, 25 and 0% of resistant individuals. There were no consistent changes in susceptibility of the susceptible strain after eight months without insecticide pressure. In the resistant strain, very highly resistant to spinosad (RF50>23,000-fold), resistance was maintained up to eight months without further exposure to spinosad. In the absence of any immigration of susceptible genes into the population, resistance was stable. In the case of the population with different initial frequency of resistant thrips, spinosad resistance declined significantly two months later in the absence of selection pressure. With successive generations, these strains did not change significantly in sensitivity. Spinosad resistance in F. occidentalis declined significantly in the absence of selection pressure and the presence of susceptible WFT. These results suggest that spinosad resistance probably is unstable under field conditions, primarily due to the immigration of susceptible WFT. Factors influencing stability or reversion of spinosad resistance are discussed.     

Bioactivity of carvacrol and thymol against Frankliniella occidentalis and Thrips tabaci

Abstract: Two constituents of essential oils, carvacrol and thymol, were tested for their effects on the feeding activity, oviposition preference and oviposition rate of Frankliniella occidentalis and Thrips tabaci . Given a choice between treated and untreated leaf discs, F. occidentalis avoided ovipositing on leaf discs treated with 1 or 0.1% thymol. In no-choice experiments, 1 and 0.1% thymol and 1% carvacrol resulted in a reduced oviposition rate of F. occidentalis compared with the control. Both constituents caused a slight reduction of the feeding damage of F. occidentalis . 1 and 0.1% carvacrol had a pronounced deterrent effect on the oviposition site selection of T. tabaci . Both constituents served as anti-ovipositants for both thrips species, albeit F. occidentalis was more affected than T. tabaci .     

五种类型农药不同剂量与施药时期对麦蚜防治效果及麦粒农药残留的影响

采用喷雾法,研究了辛硫磷、高效氯氰菊酯、抗蚜威、阿维菌素和吡虫啉5种类型农药的3种剂量在不同施药时期对麦长管蚜Sitobion avenae(Fabricius)和禾谷缢管蚜Rhopalosiphum padi(Linnaeus)的防治效果、防后对小麦千粒重的影响和籽粒中农药残留分析。结果表明,不同剂量的各种药剂,第1次施药药后1d对麦长管蚜与禾谷缢管蚜的防治效果均在80%以上,药后3d防效分别在90%和84%以上,药后5d防效分别在95%和92%以上;不同种类或不同剂量处理的防治效果之间存在显著差异(P<0.05)。第2次施药后1～5d对麦长管蚜的防效均在90%以上。与对照比较,施药1次小麦千粒重增加率为2.02%～11.93%;施药2次,千粒重增加率为8.01%～15.87%。农药残留检测结果显示,不同种类不同剂量浓度下在冬小麦扬花末期喷施1次农药和间隔5d的灌浆中期第2次农药,以及春小麦田相似农药处理,其籽粒中农药残留均有一定程度的检出,但均未超出限定标准;而在小麦乳熟期(与第1次施药间隔10d,距离成熟收获15d)喷施第2次农药,其中高效氯氰菊酯和吡虫啉已经达到或超出残留限量标准。     

Lack of fitness costs of insecticide resistance in the western flower thrips (Thysanoptera: Thripidae)

The fitness costs of spinosad and acrinathrin resistance was investigated in the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Fitness studies were conducted on susceptible and resistant strains of F. occidentalis. Resistant females were significantly more fecund (number of eggs per female) than susceptible females. The hatching rate (fertility) for both susceptible and acrinathrin-resistant strains was significantly lower than in the spinosad-resistant strain. Mean developmental time from egg to adult did not differ between thrips populations. Similarly, female longevity did not differ between populations. These data suggest that lack of fitness costs related to insecticide resistance may accelerate the development of insecticide resistance in populations of F. occidentalis from southeastern Spain.     

番茄斑萎病毒对多杀菌素抗性西花蓟马发育繁殖和药剂敏感性的影响

【目的】西花蓟马Frankliniella occidentalis (Pergande)是重要的入侵害虫,是番茄斑萎病毒（TSWV）最有效的传播媒介,TSWV对西花蓟马的生长发育有一定的影响。多杀菌素是防治西花蓟马最有效的药剂之一,但已有田间西花蓟马对多杀菌素产生抗药性的报道。TSWV对抗性西花蓟马是否也有影响及程度如何尚不清楚。本研究通过对此问题进行深入研究,以期为进一步了解TSWV对西花蓟马的影响提供依据。【方法】应用特定年龄-龄期及两性生命表的方法,研究用番茄斑萎病毒处理和未处理的多杀菌素抗性和敏感西花蓟马种群的生物学特性;用叶管药膜法测定不同处理种群对3种药剂（多杀菌素、甲氨基阿维菌素苯甲酸盐和虫螨腈）的敏感性变化。【结果】对于抗性品系,TSWV处理后西花蓟马的发育历期缩短,雌成虫寿命和产卵量略高,但与对照组差异不显著(P＞0.05),内禀增长率（r）和净生殖率（R₀）分别为0.0433 d^-1和2.210,显著高于对照组（分别为0.0356 d^-1和1.972）（P ≤ 0.001）。对于敏感品系,TSWV处理后西花蓟马的发育历期缩短,雌雄成虫寿命均显著延长（P ≤ 0.001）,产卵量也略有提高,R₀为4.125,显著高于对照组（3.979）（P ≤ 0.001）。TSWV处理后敏感和抗性西花蓟马对多杀菌素的敏感性没有发生明显变化,对甲氨基阿维菌素苯甲酸盐和虫螨腈的敏感性显著降低。【结论】番茄斑萎病毒对多杀菌素敏感和抗性西花蓟马均有直接有利影响,病毒处理的西花蓟马发育历期缩短,繁殖能力增强,成虫寿命延长,对药剂的敏感性降低。