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Inactivation of Wolbachia Reveals Its Biological Roles in Whitefly Host  [PDF]
Xia Xue, Shao-Jian Li, Muhammad Z. Ahmed, Paul J. De Barro, Shun-Xiang Ren, Bao-Li Qiu
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048148
Abstract: Background The whitefly Bemisia tabaci is cryptic species complex composed of numerous species. Individual species from the complex harbor a diversity of bacterial endosymbionts including Wolbachia. However, while Wolbachia is known to have a number of different roles, its role in B. tabaci is unclear. Here, the antibiotic rifampicin is used to selectively eliminate Wolbachia from B. tabaci so as to enable its roles in whitefly development and reproduction to be explored. The indirect effects of Wolbachia elimination on the biology of Encarsia bimaculata, a dominant parasitoid of B. tabaci in South China, were also investigated. Methodology/Principal Finding qRT-PCR and FISH were used to show that after 48 h exposure to 1.0 mg/ml rifampicin, Wolbachia was completely inactivated from B. tabaci Mediterranean (MED) without any significant impact on either the primary symbiont, Portiera aleyrodidarum or any of the other secondary endosymbionts present. For B. tabaci MED, Wolbachia was shown to be associated with decreased juvenile development time, increased likelihood that nymphs completed development, increased adult life span and increased percentage of female progeny. Inactivation was associated with a significant decrease in the body size of the 4th instar which leads us to speculate as to whether Wolbachia may have a nutrient supplementation role. The reduction in nymph body size has consequences for its parasitoid, E. bimaculata. The elimination of Wolbachia lead to a marked increase in the proportion of parasitoid eggs that completed their development, but the reduced size of the whitefly host was also associated with a significant reduction in the size of the emerging parasitoid adult and this was in turn associated with a marked reduction in adult parasitoid longevity. Conclusions/Significance Wolbachia increases the fitness of the whitefly host and provides some protection against parasitization. These observations add to our understanding of the roles played by bacterial endosymbionts.
Detection of Endosymbionts in Different Bemsia tabaci Populations and Their Effects on Whitefly Host

薛夏, 李绍建, 陈驹坚, 任顺祥, 邱宝利
Hans Journal of Agricultural Sciences (HJAS) , 2012, DOI: 10.12677/hjas.2012.21002
Abstract: 烟粉虱Bemisia tabaci是一种世界性分布的农业害虫。本文利用PCR扩增和DNA测序技术,研究了野生和实验室饲养的烟粉虱B型和Q型种群内共生菌的感染情况;并利用利福平对Q型烟粉虱实验室种群体内的共生菌进行了灭活处理,就处理前后烟粉虱的生物学特性变化进行比较。研究结果表明,所检测的的烟粉虱种群中均有初生共生菌Candidatus Portiera aleyrodidarum的感染,而次生共生菌Wolbachia和杀雄菌Arsenophonus在不同生境下的烟粉虱种群内,其感染率存在较大差异。利用1.0 mg/ml的利福平对饲养型的Q型烟粉虱成虫进行处理,48 h后处理样本体内Wolbachia的感染检测为阴性,而初生共生菌Candidatus和杀雄菌Arsenophonus仍为阳性。共生菌灭活处理后,烟粉虱成虫单雌产卵量明显下降,由36.9粒/头下降至26.4粒/头;F1代的发育历期延长,F1代种群中雄性比例有较大幅度增加,由对照种群中的45.28%上升至58.06%。本文研究表明,不同生境下,烟粉虱体内的共生菌类群存在差异,次生共生菌Wolbachia对烟粉虱的发育、繁殖及种群性比等方面有着明显的影响。
The sweetpotato whitefly Bemisia tabaci (Gennadius) is a globally distributed agricultural pest. The species and infection rates of different endosymbionts in field and laboratory populations of B. tabaci B and Q biotyes were detected by molecular methods. Meawhile, the endosymbionts in B. tabaci Q biotype lab population were inactivated with rifampicin, and then the biology of Wolbachia positive and negative popula-tions of B. tabaci Q biotype were compared. Rusults indicated that all the populations of B. tabaci were in-fected by the primary endosymbiont Candidatus Portiera aleyrodidarum, regardless biotype or population habitat of field or lab, while the infection of secondary endosymbionts Wolbachia and Arsenophonus were marked different in various B. tabaci populations related to biotype and habitat. Inactivated with 1.0mg/ml rifampicin for 48 h, the infection of Wolbachia in B. tabaci Q biotype was completely eliminated, but no ob-vious effect on the Candidatus and Arsenophonu in all the whitefly popualtions. Treated by rifampicin, the fecundity of female adults reduced and the developmental time of F1 offspring extended. Results also showed that the elimination of Wolbachia in B. tabaci led to the increase of male progeny proportion. In general, our current study showed that endosymbionts varied in different B. tabaci populations from various habitats and Wolbachia has significant effects on the biology of its whitefly hosts.
Factors Affecting Population Dynamics of Maternally Transmitted Endosymbionts in Bemisia tabaci  [PDF]
Huipeng Pan, Xianchun Li, Daqing Ge, Shaoli Wang, Qingjun Wu, Wen Xie, Xiaoguo Jiao, Dong Chu, Baiming Liu, Baoyun Xu, Youjun Zhang
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0030760
Abstract: While every individual of Bemisia tabaci (Hemiptera: Aleyrodidae) harbors the primary symbiont (P-symbiont) Portiera, the infection frequencies of the six secondary symbionts (S-symbionts) including Hamiltonella, Arsenophonus, Cardinium, Wolbachia, Rickettsia and Fritschea vary greatly among different populations. To characterize the factors influencing the infection dynamics of the six S-symbionts in B. tabaci, gene-specific PCR were conducted to screen for the presence of the P-symbiont Portiera and the six S-symbionts in 61 (17 B and 44 Q biotypes) field populations collected from different plant species and locations in China. All individuals of the 61 populations hosted the P-symbiont Portiera, but none of them harbored Arsenophonus and Fritschea. The presence and infection rates of Hamiltonella, Cardinium, Rickettsia, Wolbachia and their co-infections Rickettsia + Hamiltonella (RH), Rickettsia + Cardinium (RC), Hamiltonella + Cardinium (HC) and Rickettsia + Hamiltonella + Cardinium (RHC) varied significantly among the 61 field populations; and the observed variations can be explained by biotypes, sexes, host plants and geographical locations of these field populations. Taken together, at least three factors including biotype, host plant and geographical location affect the infection dynamics of S-symbionts in B. tabaci.
Co-infection and localization of secondary symbionts in two whitefly species
Marisa Skaljac, Katja Zanic, Smiljana Ban, Svetlana Kontsedalov, Murad Ghanim
BMC Microbiology , 2010, DOI: 10.1186/1471-2180-10-142
Abstract: T. vaporariorum was found to be the predominant whitefly species across Croatia, while only the Q biotype of B. tabaci was found across the coastal part of the country. Arsenophonus and Hamiltonella were detected in collected T. vaporariorum populations, however, not all populations harbored both symbionts, and both symbionts showed 100% infection rate in some of the populations. Only the Q biotype of B. tabaci was found in the populations tested and they harbored Hamiltonella, Rickettsia, Wolbachia and Cardinium, while Arsenophonus and Fritschea were not detected in any B. tabaci populations. None of the detected symbionts appeared in all populations tested, and multiple infections were detected in some of the populations. All endosymbionts tested were localized inside the bacteriocyte in both species, but only Rickettsia and Cardinium in B. tabaci showed additional localization outside the bacteriocyte.Our study revealed unique co-infection patterns by secondary symbionts in B. tabaci and T. vaporariorum. Co-sharing of the bacteriocyte by the primary and different secondary symbionts is maintained through vertical transmission via the egg, and is unique to whiteflies. This system provides opportunities to study interactions among symbionts that co-inhabit the same cell in the same host: these can be cooperative or antagonistic, may affect the symbiotic contents over time, and may also affect the host by competing with the primary symbiont for space and resources.Whiteflies (Hemiptera: Aleyrodidae) are an extremely important group of agricultural insect pests that cause serious damage by weakening plants, excreting honeydew and transmitting several hundreds of plant viruses [1]. The most economically important of these is the cosmopolitan sweetpotato whitefly Bemisia tabaci (Gennadius), which is a species complex of more than 20 biotypes. The B and Q biotypes, among the most predominant and damaging worldwide, differ in many biological parameters, including resista
福建省烟粉虱自然种群Wolbachia感染特点  [PDF]
昆虫学报 , 2008,
Abstract: Wolbachia是专性的细胞内细菌,广泛存在于节肢动物生殖组织。已有的研究结果表明,节肢动物中存在A组和B组Wolbachia,而烟粉虱Bemisiatabaci中主要检测到了B组Wolbachia。本研究从福建省采集到17个不同烟粉虱地理种群,首先通过rDNA-ITS1克隆测序鉴定了不同烟粉虱地理种群的生物型,然后采用Wolbachia16SrDNA的特异引物,并通过PCR-RFLP技术分析了不同烟粉虱地理种群中Wolbachia的感染特点。结果表明:从福建省闽侯、平潭、南平、来舟、漳平和沙县采集到的烟粉虱自然种群属于非B型,而非B型烟粉虱种群中存在广泛的超感染现象,即单个非B型烟粉虱个体中同时感染了不同型Wolbachia。相反,B型烟粉虱自然种群的个体中只感染A组Wolbachia。该研究依据密集采样的数据进一步证实了Wolbachia在烟粉虱自然种群中的分布确实与宿主的生物型密切相关,提示Wolbachia可能在烟粉虱的种群分化中发挥作用。
亚洲不同地理种群褐飞虱内共生菌wolbachia的分子检测  [PDF]
应用昆虫学报 , 2013,
Abstract: 褐飞虱是水稻的重要害虫,而wolbachia是其重要的次生共生细菌之一。为了解褐飞虱种群感染wolbachia的情况,本研究对采自世界褐飞虱主要分布区的22个地理种群感染wolbachia的情况进行了检测和分析。qpcr结果表明,除杭州2009年种群没有检测出wolbachia外,其它21个种群中都有不同程度的wolbachia感染。对wolbachia的wsp基因序列的比较和进化分析表明,褐飞虱各地理种群wolbachia都属于b群,并可进一步分为ori和con两个亚群。其中18个褐飞虱种群中的wolbachia属于ori亚群,广东清远和浙江桐乡褐飞虱种群中的wolbachia则属于con亚群,而菲律宾iloilo褐飞虱种群分别检测到同时有2个亚群wolbachia感染。本结果可为进一步研究褐飞虱与共生菌的共生关系、褐飞虱致害性变异和迁飞路线分析及利用wolbachia防治褐飞虱提供依据。
应用巢式PCR-DGGE技术分析稻虱缨小蜂体内Wolbachia的多样性  [PDF]
昆虫学报 , 2011,
Abstract: 以采集自中国杭州和菲律宾的稻虱缨小蜂Anagrusnilaparvatae为研究对象,采用巢式PCR扩增Wolbachia的16SrDNA和wsp基因片段,并用DGGE分析稻虱缨小蜂体内Wolbachia的多样性。基于16SrDNA基因的分析结果准确地检测到稻虱缨小蜂体内细菌主要是Acinetobactersp.,Methylophilussp.,Acidovoraxsp.,Burkholderiasp.和Wolbachiasp.。基于wsp基因的分析结果显示,杭州种群感染的Wolbachia属于A组的Mors亚组,菲律宾种群感染的Wolbachia属于A组的Dro亚组。结果说明,巢式PCR-DGGE是寄生蜂体内Wolbachia检测和多样性分析的有效方法,其中16SrDNA基因是检测Wolbachia存在的较佳分子标记,wsp基因是Wolbachia多样性分析以及种属鉴定和分型的较佳分子标记。
转染从灰飞虱提取的Wolbachia对豆叶螨繁殖适合度和寿命的影响  [PDF]
昆虫学报 , 2014,
Abstract: 【目的】Wolbachia是广泛存在于节肢动物体内的一类母系遗传的共生菌,能够通过多种机制调节节肢动物的生殖。近年来,为了更进一步地探究Wolbachia与寄主之间的互作机制,许多研究者展开了Wolbachia的人工转染研究。【方法】我们在实验室条件下将灰飞虱Laodelphaxstriatellus(Fallén)感染的Wolbachia提取纯化后,利用显微注射的方法导入豆叶螨TetranychusphaselusEhara体内。研究了注入从灰飞虱提取的Wolbachia和豆叶螨自然感染Wolbachia对豆叶螨繁殖适合度和寿命的影响,并测定了两种Wolbachia的密度随豆叶螨日龄增长的变化情况。【结果】结果显示,外源Wolbachia在豆叶螨体内的拷贝数极低,仅为自然感染豆叶螨体内Wolbachia拷贝数的0.5%左右。与自然感染的Wolbachia不同,外源Wolbachia在豆叶螨种群中不能引起胞质不亲和,但能够显著降低雌螨的产卵量。【结论】本研究表明,来自灰飞虱的Wolbachia具有抑制豆叶螨种群扩张的潜在能力,对豆叶螨生物防治具有一定的应用价值。
基于16SrDNA序列的Wolbachia的检测及分型  [PDF]
昆虫学报 , 2009,
Abstract: Wolbachia是广泛分布于节肢动物体内的一类共生细菌。采用16SrDNA特异片段的PCR-RFLP方法对烟粉虱Bemisiatabaci(Gennadius)不同生物型及米蛾Corcyracephalonica(Stainton)共生菌Wolbachia进行了检测与分型分析。基于wsp基因对烟粉虱共生菌B组Wolbachia以及米蛾共生菌Wolbachia进行了系统树分析,并对相应的Wolbachia16SrDNA特异片段进行了克隆、测序以及序列比对。结果表明:16SrDNA的特异片段经NheⅠ酶切后RFLP图谱可有效检测与鉴别Wolbachia。烟粉虱共生菌Wolbachia的16SrDNA特异片段经VspⅠ酶切后可得到预期RFLP图谱,而米蛾共生菌B组Wolbachia(基于wsp序列分析为B组)则产生不同的RFLP图谱。序列分析表明,Nauru型烟粉虱体内B组Wolbachia的16SrDNA片段序列与已知B组Wolbachia对应序列(DQ278884)同源性为100%;米蛾体内B组Wolbachia16SrDNA特异片段有碱基变异,并存在于VspⅠ识别位点内,这是导致VspⅠ酶切后RFLP图谱不同的原因。结果提示,B组Wolbachia16SrDNA特异片段经VspⅠ酶切的RFLP图谱存在多态性。本研究结果可为今后Wolbachia的检测与分型提供借鉴。
Ppopulation Composition of Gennadius and Dominant Biotype in Vegetable Field in Shaanxi Province

- , 2018, DOI: 10.7606/j.issn.1004-1389.2018.12.019
Abstract: 旨在研究陕西菜田烟粉虱和白粉虱的数量结构,为粉虱风险评估和防治策略制定提供理论依据。利用定点调查与普查相结合的方法,对陕西关中、陕南和陕北不同生态区、不同季节、不同蔬菜作物以及不同菜田烟粉虱和温室白粉虱的种群分布和组成进行研究,并结合 mtDNA-CO1标记基因实现对陕西菜田烟粉虱的生物型鉴定。结果表明,烟粉虱和温室白粉虱的分布和种群组成因地区、季节、作物种植模式不同而异。其中烟粉虱均呈现优势分布,并占到种群数量的67.2%~100%。采用标记基因技术、序列同源性分析和系统发育研究,明确了陕西菜田烟粉虱生物型为Q型烟粉虱。
In order to determine the population composition and distribution of Bemisia tabaci and Trialeurodes vaporariorum Gennadius, and provide the theoretical basis for risk assessment, prevention and control, Bemisia tabaci and Trialeurodes vaporariorum Gennadius were collected from different ecological areas, seasons, vegetables and planting patterns in South, Middle and North of Shaanxi province, to analyze their composition and distribution with mathematical methods. In addition, the marker gene of mtDNA-CO1 was used for the biotypes identification of Bemisia tabaci Gennadius. The results indicated that the population proportion and distribution of Bemisia tabaci and Trialeurodes vaporariorum Gennadius were influenced by the different host vegetables and climatic factors. For Bemisia tabaci Gennadius, they showed the dominant distribution (67.2%-100%) in whole field. Interestingly, this kind of Bemisia tabaci Gennadius were ifentified as biotype Q followed the gene amplification, sequences alignment and phylogenetic analysis.
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