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1.
准噶尔盆地南缘和阿拉善左旗9个梭梭居群种间系统发育和亲缘关系研究 总被引：1，自引：0，他引：1
对荒漠植物梭梭进行ITS序列测定,研究不同梭梭居群系统发育和亲缘关系.材料源于准噶尔盆地南缘及内蒙古阿拉善左旗.结果表明:所测序列经排序后全长732bp.遗传距离矩阵表明:阜康与阿左旗的梭梭居群间遗传距离最小;石河子150与富蕴的居群遗传距离最大.系统发育树结果显示:石河子121、克拉玛依、杜热和150的居群聚为一支;阜康与阿左旗居群以92％的自展支持率相聚;戈壁藜等三种植物作为外类群. 相似文献
2.
四纹豆象是口岸检疫中经常截获的种类,本文以四纹豆象及其近缘种为研究对象,测定分析了COI基因516 bp碱基序列。序列分析结果表明:保守位点为353个,变异位点为163个,简约信息位点为134个,自裔位点为29个。基于Kimura 2-parameter模型分析遗传距离,结果显示:种内遗传距离介于0.001~0.013之间,平均遗传距离为0.008,种间遗传距离介于0.114~0.193,平均遗传距离为0.161。采用邻接法构建的COI基因序列系统发育树显示,同一物种聚为同一小支,且分支自展值均为100%。结果表明应用COI基因片段对四纹豆象及其近缘种进行分子鉴定具有可行性。 相似文献
3.
广西香蕉细菌性软腐病病原鉴定及生物学特性研究 总被引：2，自引：0，他引：2
为明确引起广西香蕉细菌性软腐病的病原,采用组织分离法从染病的香蕉组织中分离病原菌,通过柯赫氏法则验证其致病性。对病原菌进行形态学观察、分子鉴定、生理生化测试及生物学特性测定。结果表明,从染病蕉头和蕉果分离到的病原菌,其菌株的形态特征、生理生化测试结果与Dickeya sp.基本一致,16S rDNA基因序列与Dickeya属细菌的同源性达99%;其最适培养温度为28℃,最适pH为7.0。病原菌的dnaX、gryB和recA基因序列与D.zeae的同源性均在97%以上。多基因系统发育树显示,病原菌与所有的D.zeae细菌聚在同一个最小进化分支里,自展支持率为100%。根据以上结果,将引起广西香蕉细菌性软腐病的病原菌鉴定为Dickeya zeae。同时,测定7种杀菌剂对GR-1菌株的室内毒力,46%氢氧化铜WG的EC_(50)最低,为186.69 mg/L;其500倍稀释液对GR-1菌株的抑菌效果最好,达76.89%。 相似文献
4.
本文选用31个形态学特征及1个生物学特征为依据,对肉食螨亚科23属进行了支序分析,探讨国内已知肉食螨亚科属间系统发育关系.支序分析将肉食螨属归为一个独立单元,随后,其余各属被分为两个分支,其中一支由贝氏螨属、暴螯螨属、扎扇毛螨属、螯钳螨属、螯梳螨属和螯螨属构成.支序分析较好的解决了肉食螨亚科内的姐妹群关系,共形成9个稳定的姐妹群关系,其中(平单梳螨(单梳螨属+新单梳螨属))、(前螯螨属(螯颊螨属+真颊螨属))、(贝氏螨属+螯钳螨属)三组姐妹群关系较好的支持了Volgin肉食螨亚科分族系统. 相似文献
5.
本研究利用DNA条形码技术对13种小花蝽属Orius Wolff昆虫进行了鉴定,进行了59条COI基因序列碱基组成及种内、种间遗传距离的分析,采用邻接法、最大简约法、贝叶斯推论法构建了系统发育树。结果表明,小花蝽属昆虫COI基因序列碱基组成与典型的昆虫线粒体DNA一致,A+T平均含量(66.4%)明显高于G+C含量,密码子的第3位A+T含量高达90.7%,碱基替换多为同义替换;13种小花蝽种内平均遗传距离为0.008,种间平均遗传距离为0.128,种内、种间遗传距离没有重叠区域。3种方法构建的系统发育树的聚类分析与形态学鉴定结果基本一致,除微小花蝽Orius minutus(Linnaeus)可能存在隐存种现象外,其他同一种群的不同个体单独聚为一支。利用DNA条形码技术对小花蝽属昆虫进行物种快速分子鉴定具有可行性。 相似文献
6.
根据高粱属核糖体基因转录间隔区(ITS)序列设计通用引物S9/S3,分别扩增了假高粱及其几个近似种的ITS区段,并对PCR产物进行了序列测定和分析.扩增的序列长度为559～564bp.序列分析的结果表明S. halepense、 S. silk、 S. vulgare×S. sudanense、 S. vulgare、高粱S. bicolor等属于同一聚类组,亲缘关系比较近,同源性为97.9%～100%.S. nitidum和S. versicolor属于另一个聚类组,亲缘关系比较近,同源性为97.7%.S. halepense和S. nitidum、S. versicolor ITS区序列差异大,亲缘关系较远,同源性仅为90.3%.序列分析结果支持S. nitidum属于Parasorghum区组. 相似文献
7.
甘肃省马铃薯镰刀菌干腐病优势病原的分离鉴定 总被引：11，自引：0，他引：11
为明确甘肃马铃薯镰刀菌干腐病的优势病原,2006 年12 月~ 2007 年3 月由西至东从甘肃张掖、天祝、永登、临洮、渭源和西和等6 县市的马铃薯贮藏窖中采集表现有镰刀菌干腐病症状的马铃薯薯块,以组织分离法分离病原,单孢纯化镰刀菌(Fusarium spp. )菌株后,以形态学为基础,参照Nelson 镰刀菌分类系统进行鉴定。结果表明:6 个采样区共分离到293株镰刀菌菌株,其中以接骨木镰刀菌(F. sambucinum)和茄病镰刀菌(F. solani)出现频率高,是优势种。分析发现第一优势种随采样区而异,张掖、天祝和渭源采集的样品中茄病镰刀菌分离频率分别为42. 6% 、42. 1% 和32. 4% ,接骨木镰刀菌分离频率分别为14. 8% 、5. 3% 和26. 5% ,茄病镰刀菌为第一优势种;永登、临洮和西和采集的样品中接骨木镰刀菌分离频率分别为52郾1% 、50. 9% 和55. 2% ,茄病镰刀菌的分离频率分别为23. 3% 、32. 7% 和20. 7% ,接骨木镰刀菌为第一优势种。本文进一步对其在PDA、CLA 上的培养特征进行了观察和描述。按照柯赫氏法则用混合菌株接种法对大西洋(Atlantic)、夏波蒂(Shepody)以及一地方品种进行致病性测定,证实了优势菌种对块茎的致病性。利用EF鄄1琢基因引物(EF鄄1H 和EF鄄2T)对接骨木镰刀菌菌株GAUF鄄F12 进行基因组DNA 的PCR 扩增,将PCR 产物回收测序后在GenBank 上比对,菌株GAUF鄄F12 与GenBank 登记的接骨木镰刀菌5 个菌株的同源性均达99% ;用DNASTAR 分析软件将同源性较高的登记菌株的序列与GAUF鄄F12 菌株构建同源性树,结果表明:该菌株与以上5 个接骨木镰刀菌菌株均位于同源性树的同一分支,聚为一类,与形态学的鉴定结果一致。 相似文献
8.
为研究黑肩绿盲蝽Cyrtorhinus lividipennis的谱系地理和遗传结构, 本文测定并分析了其线粒体基因组全序列。结果表明:黑肩绿盲蝽线粒体基因组全长16 835 bp (GenBank登录号:OK149286), 包括13个蛋白质编码基因(PCGs), 22个tRNA基因, 2个rRNA基因和1个非编码区, 呈闭合双链环状DNA分子结构。线粒体基因组中A+T含量高达76.8%, G+C含量为23.2%, 呈现明显的AT偏向性; 13个蛋白质编码基因均以通用密码子ATN作为起始密码子; 蛋白质编码基因中呈现出明显的氨基酸偏好性, 异亮氨酸含量占比最高, 为10.78%; 22个tRNA基因中有21个tRNA形成典型的三叶草式二级结构; 系统发育树显示, 盲蝽科的11个种聚为两大分支, 黑肩绿盲蝽以99％的自展支持率位于其中的一个分支内。本研究结果将为黑肩绿盲蝽作为天敌昆虫来防治水稻害虫提供帮助。 相似文献
9.
蔬菜保护地木霉菌rDNA-ITS序列和UP-PCR遗传多样性分析 总被引：2，自引：0，他引：2
采用传统形态学分类和ITS序列比对的方法,研究蔬菜保护地土壤中木霉菌种群分布和遗传多样性。木霉菌分离培养结果显示,共获得397株木霉菌,鉴定出11个种,分别为:长枝木霉Trichoderma longibrachiatum、深绿木霉T.atroviride、哈茨木霉T.harzianum、粘绿木霉T.viren、微孢木霉T.minutisporum、拟康木霉T.pseudokoningii、黄绿木霉T.aureoviride、非钩木霉T.inhamatum、棘孢木霉T.asperellum、长孢木霉T.longipile和螺旋木霉T.helicum。经ITS序列建立系统发育树后,将木霉菌分为5个组。用5条通用引物经UP-PCR扩增后,扩增出46条谱带,其中多态性条带43条,占总条带数的93.5%。遗传多样性分析表明,当相似系数为0.80时,可将24个菌株划分为9个组。UP-PCR与ITS序列相比,更能体现木霉菌种间和种内的亲缘关系及遗传差异性,可以作为木霉菌分类的辅助方法。 相似文献
10.
通过采用营林卫生伐措施,清理遭受病虫危害的松树病枯死树、衰弱木、被压木、枯枝等,分析比较长年清理、集中清理和不清理等不同处理方式对松墨天牛成虫种群数量动态和松病枯死树数量变化情况。结果表明：经3年的处理,3种处理方式对松墨天牛成虫种群数量动态和松病枯死树数量变化差异明显。松墨天牛成虫虫口减退率和防治效果分别为：长年清理为94.09%和94.62%、集中清理为52.82%和57.03%,不清理（CK）天牛成虫虫口数量增加9.91%;松病枯死树减退率和防治效果分别为：长年清理为100%和100%、集中清理为69.28%和86.53%,不清理（CK）松病枯死树数量增加128.02%。 相似文献
11.
Traditionally,Atraphaxis,Calligonum,Pteropyrum and Parapteropyrum are included in the tribe Atraphxideae.Recently,sequence data has revealed that this tribe is not monophyletic.The structure of the tribe was examined by adding more taxa and sequences to clarify the congruence between morphology and molecular phylogeny,the systematic placements of four genera in Polygonaceae,as well as the infra-generic relationships of Atraphaxis and Calligonum within Atraphaxideae.Five chloroplast genes,atpB-rbcL,psbA-trnH,trnL–trnF, psbK-psbI,and rbcL of Atraphaxis,Calligonum,Pteropyrum,and Parapteropyrum were sequenced.The non-monophyly of Atraphaxideae was confirmed.Atraphaxis and Calligonum,respectively,formed a monophyletic group that was well supported.Calligonum is closely related to Pteropyrum;Atraphaxis is sister to Polygonum s.str.; and Parapteropyrum is allied with Fagopyrum.Although the morphology suggested the four genera should form a tribe,the molecular data indicated Atraphaxideae was not one monophyletic group.The clades identified within Atraphaxis corresponded well with the current sectional classification based on morphological features.As for Calligonum,Medusa was identified as a non-monophyletic section. 相似文献
12.
草地贪夜蛾Spodoptera frugiperda是一种重要的世界性害虫,2019年1月传入我国云南。草地贪夜蛾可以为害玉米、高粱、水稻等350余种植物,给我国农林生产带来巨大威胁。随着测序技术的飞速发展,全线粒体基因组越来越多地被应用到昆虫学研究领域。本研究以灯蛾科2种昆虫作为外群,基于全线粒体基因组数据,重建了夜蛾科22种昆虫的系统发育关系,对草地贪夜蛾的系统发育地位进行了探究。研究结果发现草地贪夜蛾与斜纹夜蛾和甜菜夜蛾的亲缘关系最近,与斜纹夜蛾构成姐妹群关系。研究结果为未来的草地贪夜蛾的防控研究提供了理论基础,同时为草地贪夜蛾的防控方法提出了一些建议。 相似文献
13.
ABSTRACT A worldwide collection of Fusarium oxysporum f. sp. cubense was analyzed using anonymous, single-copy, restriction fragment length polymorphism (RFLP) loci. Several lines of evidence indicated that this pathogen has a clonal population structure. Of the 165 isolates examined, only 72 RFLP haplotypes were identified, and nearly half the isolates were represented by the five most common haplotypes. Individuals with identical haplotypes were geographically dispersed, and clone-corrected tests of gametic disequilibrium indicated significant nonrandom association among pairs of alleles for 34 of 36 loci tested. Parsimony analysis divided haplotypes into two major branches (bootstrap value = 99%) that together contained eight clades supported by significant bootstrap values. With the exception of two isolates, all isolates within a vegetative compatibility group were in the same clade and clonal lineage. Clonal lineages were defined by isolates having coefficients of similarity between 0.94 and 1.00. Ten clonal lineages were identified, and the two largest lineages had pantropical distribution. Minor lineages were found only in limited geographical regions. Isolates composing one lineage (FOC VII) may represent either an ancient genetic exchange between individuals in the two largest lineages or an ancestral group. The two largest lineages (FOC I and FOC II) and a lineage from East Africa (FOC V) are genetically distinct; each may have acquired the ability to be pathogenic on banana independently. 相似文献
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15.
The small subunit ribosomal RNA gene (SSU rDNA) of two freshwater and one marine species of the genus Chloromyxum Mingazzini, 1890 were sequenced. The SSU rDNA trees obtained show the phylogenetic position of the marine species Chloromyxum leydigi Mingazzini, 1890 to be at the base of the freshwater clade, being well supported by a high bootstrap value. Chloromyxum cyprini Fujita, 1927 is closely related to Chloromyxum truttae Léger, 1906 and they represent a sister branch to raabeia sp., Myxidium sp. and Myxidium truttae Léger, 1930. Chloromyxum legeri Tourraine, 1931 is in a position ancestral to Myxidium lieberkuehni Bútschli, 1882 and Sphaerospora oncorhynchi Kent, Whitaker et Margolis, 1993. Three newly sequenced species of the genus Chloromyxum represent three separate lineages within the myxosporean tree and do not support the monophyly of this genus. 相似文献
16.
Franco D. Fern��ndez Vilma C. Conci Daniel S. Kirschbaum Luis R. Conci 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(1):1-4
Strawberry (Fragaria x ananassa Duch. cv. Camino Real) plants showing phyllody symptoms were detected in production fields in Bella Vista (Corrientes province, Argentina). DNA from all symptomatic samples analyzed yielded fragments of the expected size in PCR reactions using phytoplasma universal primers. DNA from asymptomatic plants yielded no products. The associated phytoplasma was designated as Argentinean Strawberry Phyllody (ASP). The ASP sequence of the 16S rRNA gene showed 99?C98% homology with members of the 16SrVII ash yellows group. The putative RFLP profile was indistinguishable from the Argentinean alfalfa witches?? broom (ArAWB) phytoplasma. The phylogenetic analysis of nearly full-length 16S rDNA sequence and 16S-23S spacer region yielded a consensus tree wherein ASP clustered into the ash yellows group (16Sr VII) with high confidence values (95), generating a separated branch (100 bootstrap value) together with ArAWB (16Sr VII-C). In Argentina, the 16Sr VII group was also detected in alfalfa (Medicago sativa L.) crops, and weeds [Artemisa annua L. and Conyza bonariensis (L.) Cronquist]. To our knowledge, this is the first report of a phytoplasma from the 16Sr VII group affecting strawberries in Argentina and worldwide. 相似文献
17.
Chelex100法提取甘薯小象甲DNA及云南地区甘薯小象甲的分子鉴定 总被引：1，自引：0，他引：1
甘薯小象甲是国内外重要的检疫性害虫,除本身为害薯块外,引起的伤口还会诱致病菌侵入,使受害薯块发生恶臭和苦味无法食用。准确鉴定云南地区的甘薯小象甲,特别是研究其遗传变异可为检疫提供依据。本研究采集了云南元谋县甘薯小象甲,采用Chelex-100法快速提取甘薯小象甲基因组DNA,分别对雌雄成虫rDNA ITS-1序列进行系统发育分析,首次发现云南元谋县的甘薯小象甲属于东亚分支的东南亚亚支,与我国之前报道的甘薯小象甲属于东亚分支的东北亚亚支不同,说明云南元谋县的甘薯小象甲种群来源与中国广东、福建、浙江和重庆的种群来源不同。 相似文献
18.
Abstract: Small subunit rRNA sequences were obtained from 38 representatives mainly of the nematode orders Spirurida (Camallanidae, Cystidicolidae, Daniconematidae, Philometridae, Physalopteridae, Rhabdochonidae, Skrjabillanidae) and, in part, Ascaridida (Anisakidae, Cucullanidae, Quimperiidae). The examined nematodes are predominantly parasites of fishes. Their analyses provided well-supported trees allowing the study ofphylogenetic relationships among some spirurine nematodes. The present results support the placement of Cucullanidae at the base of the suborder Spirurina and, based on the position of the genus Philonema (subfamily Philoneminae) forming a sister group to Skrjabillanidae (thus Philoneminae should be elevated to Philonemidae), the paraphyly of the Philometridae. Comparison of a large number of sequences of representatives of the latter family supports the paraphyly of the genera Philometra, Philometroides and Dentiphilometra. The validity of the newly included genera Afrophilometra and Caranginema is not supported. These results indicate geographical isolation has not been the cause of speciation in this parasite group and no coevolution with fish hosts is apparent. On the contrary, the group of South-American species ofAlinema, Nilonema and Rumai is placed in an independent branch, thus markedly separated from other family members. Molecular data indicate that the skrjabillanid subfamily Esocineminae (represented by Esocinema bohemicum) should be either elevated to the rank of an independent family or Daniconematidae (Mexiconema africanum) should be decreased to Daniconematinae and transferred to the family Skrjabillanidae. Camallanid genera Camallanus and Procamallanus, as well as the subgenera Procamallanus and Spirocamallanus are confirmed to be paraphyletic. Paraphyly has also been found within Filarioidea, Habronematoidea and Thelazioidea and in Cystidicolidae, Physalopteridae and Thelaziidae. The results of the analyses also show that Neoascarophis, Spinitectus and Rhabdochona are monophyletic, in contrast to the paraphyletic genus Ascarophis. They further confirm the independence of two subgenera, Rhabdochona and Globochona, in the genus Rhabdochona. The necessity of further studies of fish-parasitizing representatives of additional nematode families not yet studied by molecular methods, such as Guyanemidae, Lucionematidae or Tetanonematidae, is underscored. 相似文献