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1.
DNA条形码(DNA Barcoding)是近几年来国际生物学研究的热点之一。但是在国内,相关概念还存在不同程度的模糊,不利于研究工作的进一步开展。本文在对DNA条形码与DNA分类(DNA Taxonomy)两个不同概念进行辨析的基础上,回顾与总结了DNA条形码的产生背景与应用进展,并对DNA条形码目前所面临的基因交流、取样、计算方法等问题进行了总结和分析,最后对DNA条形码研究前景进行了展望。  相似文献   

2.
 剪股颖粒线虫[Anguina agrostis (Steinbuch,1799) Filipjev,1936]、小麦粒线虫[Anguina tritici (Steinbuch,1799) Filipjev,1936]和维氏粒线虫[Anguina wevelli (Van den Berg,1985) Siddiqi,2000]都是重要的植物病原线虫,它们在成熟种子和虫瘿中的虫态通常是幼虫,而这3种线虫的幼虫形态非常相似,难以根据其特征对它们进行快速准确的种类鉴定。本研究根据这3种线虫的rDNA-ITS区域序列,分别设计筛选了特异性引物AgrF1/AgrR1、TriF1/TriR1、WevF1/WevR1,构建了这3种线虫单条幼虫多重PCR检测体系,获得3个大小差异明显的片段,表明这些引物设计合理,适合这3种线虫的快速准确检测。  相似文献   

3.
通过采用Fullaondo(1999)研究的特异引物检测方法,对来自英国和比利时的两个马铃薯金线虫(Globodera rostochiensis)种群和英国的一个马铃薯白线虫(G.pallida)种群的DNA进行扩增,其产物以大肠杆菌(Eschetichia coli)为受体菌,经过连接、转化和克隆纯化,筛选获得阳性克隆.经PCR鉴定和测序,英国和比利时的马铃薯金线虫种群的特异性谱带分别是357bp和350bp,而英国的马铃薯白线虫的谱带是782bp,与Fullaondo等人研究报道结果基本相符,从而鉴别出来自不同地理种群的马铃薯金线虫和白线虫.  相似文献   

4.
柑橘黄龙病病原DNA微量提取方法比较   总被引:3,自引:0,他引:3  
对比分析了3种黄龙病病原DNA微量提取方法,方法1和方法2分别采用Sandrine等人和Hung等人的黄龙病病原DNA提取方法,但取样量分别由100mg和250mg减少为20mg和10mg;方法3采用周常勇等人的微量核酸提取方法,取样量为10mg.实验结果表明:方法1提取的病原DNA浓度低、杂质多,PCR效果差;方法2提取的病原DNA浓度较高、杂质少,PCR效果好,但提取周期较长,不适合大批量样品的PCR快速检测;方法3提取的病原DNA浓度较高、杂质少,PCR效果好,且提取速度快,适宜大批量样品的PCR快速检测.  相似文献   

5.
双生病毒——一类值得重视的植物病毒   总被引:24,自引:0,他引:24  
 双生病毒是世界范围内广泛发生的一类植物单链DNA病毒,已在多种作物上引起严重危害。重组是导致双生病毒变异和病害流行的重要原因。近年来,在单组份双生病毒中发现有新型卫星DNA分子——DNAβ,DNAβ是病毒致病所必需的。本文就双生病毒的危害性、病毒的重组、DNAβ的发现及与致病性的关系、双生病毒与伴随的小分子DNA形成病害复合体、双生病毒DNA-A和小分子DNA的进化关系等问题进行了简要评述。  相似文献   

6.
The plant–parasitic nematode Longidorus poessneckensis from the Czech Republic was morphologically and molecularly characterised. Molecular analyses were carried out using mitochondrial DNA (cytochrome c oxidase subunit 1—cox1) and ribosomal DNA (ITS2—second internal transcribed spacer, 18S gene and D2/D3 expansion segments of the 28S gene), which were amplified and sequenced. Phylogenetic relationship of L. poessneckensis with three morphologically closely related species, i.e. L. macrosoma, L. helveticus and L. uroshis, was inferred by using maximum likelihood and maximum parsimony methods, with a female of Xiphinema diversicaudatum and a bivulval female of X. vuittenezi as outgroups. All multiple alignments yielded similar basic trees supporting the uniqueness of L. poessneckensis and the validity of the four Longidorus species identified using morphological characters. Phylogenetic analyses revealed that L. poessneckensis is more closely related to L. macrosoma and L. helveticus than to L. uroshis. High inter-population diversity (19%) was observed across the cox1 gene between two populations of L. poessneckensis.  相似文献   

7.
棉花曲叶病研究进展   总被引:1,自引:0,他引:1  
 棉花曲叶病(Cotton leaf curl disease,CLCuD)是棉花上的重要病害,在巴基斯坦和印度已造成严重危害。已发现7种双生病毒与亚洲和非洲发生的CLCuD相关,在田间这些双生病毒常复合侵染且病毒基因组重组现象较为普遍。CLCuD伴随不同类型的小分子DNA,其中新型卫星DNA分子——DNAβ与CLCuD致病性紧密相关,是诱导田间典型症状所必需的。重组导致CLCuD的病毒多样化,而DNAβ分子能与不同双生病毒互作,这可能是引起CLCuD流行的重要原因。本文介绍了CLCuD的分布与危害、病害病原致病因子的发现及CLCuD病害复合体各组份之间的互作、病毒及小分子DNA的变异与进化关系、病害流行及防治等方面的研究进展。  相似文献   

8.
中国猕猴桃细菌性花腐病菌的鉴定   总被引:4,自引:0,他引:4  
 从福建、湖南和湖北猕猴桃病花上分离到能引起花腐病的32个细菌菌株,经细菌学和BiologGN测试板测定,可以看出中国的猕猴桃细菌性花腐病菌与新西兰的猕猴桃花腐病菌、丁香假单胞菌丁香致病变种Pseudomonas syringae pv.syringae和绿黄假单胞菌P.viridiflava相似,与萨氏假单胞菌P.savastanoi和猕猴桃溃疡病菌P.syringae pv.actinidiae有更多的不同,但是DNA/DNA同源性测定结果却显示出中国的菌株可分为2个类型:第1个类型与新西兰猕猴桃花腐病菌和萨氏假单胞菌有很高的同源性,第2类型与绿黄假单胞菌有很高的同源性,说明中国菌株分别属于这2个种。第1类型来自于福建和湖北,第2类型来自于湖南。  相似文献   

9.
长期的观察发现,不同柑橘品种感染黄龙病后出现的病症也不尽相同,针对这种现象本文检测了浙江柑橘黄龙病病原β-操纵子核糖体蛋白基因并进行了序列比对,BLAST比对结果说明所扩增的基因序列之间差异性为0,与基因库(NCBI)中黄龙病亚洲韧皮杆菌DNA序列相似性为100%,由此说明浙江柑橘黄龙病病原β-操纵子核糖体蛋白基因并未发生变异,出现上述现象可能是其他基因发生变异或者与品种的抗病性有关。  相似文献   

10.
An extensive survey ofBemisia tabaci populations covering the southern half of the island of Cyprus was conducted in 2006 and 2007 in order to define the biotype status of the pest. Sampling was done both on protected and outdoor cultivations of vegetables and ornamental plants. Biotype identification was performed using molecular diagnostics based on the mitochondrial cytochrome oxydase I gene. Our results indicated the presence of only the biotype B in all 25 collections. http://www.phytoparasitica.org posting August 8, 2008.  相似文献   

11.
The genetic characteristics of the dominant genotypes of Phytophthora infestans in Japan (US-1, JP-1, Japanese A1-A, A1-B) were compared. Differences were evident in the peptidase genotype, amplified fragment length polymorphism, and RG57 DNA fingerprints. Almost all of the fingerprint bands for the Japanese genotype A1-B were also present in JP-1 and Japanese A1-A, and few bands were unique to Japanese A1-B. These results suggest that the Japanese A1-B genotype was generated from sexual reproduction involving Japanese A1-A and JP-1 or related genotypes.  相似文献   

12.
13.
The mating type, glucose-6-phosphate isomerase (Gpi) and peptidase (Pep) genotypes, RG57 fingerprint, and mitochondrial DNA (mtDNA) haplotype of Chinese isolates of Phytophthora infestans collected in Hebei and Gansu in 1996 were compared with those of Japanese isolates collected during 1997–2000. The Chinese isolates were divided into four genotypes, one of which was identical to the dominant Japanese genotype, A1-A (mating type A1; Gpi 100/100; Pep 100/100; RG57 100010001100110100011001110: 1–25, 14a, and 24a; and mtDNA haplotype IIa). Comparison of the genotypes with reported data revealed that some completely and partially identical genotypes occur in Russia and parts of Europe. The other two A1 genotypes and one A2 genotype were also detected in Gansu (Gpi 100/100, Pep 100/100, and mtDNA haplotype Ia), which were regarded as unique to this region.  相似文献   

14.
 运用致病力和DNA多态性检测中国东北地区的35个大豆灰斑病菌分离物的遗传变异、根据菌株在9个品种(系)上的致病力反应可将其分为7个组。利用13个随机引物扩增供试菌株共计产生105个RAPD标记,其中78.1%具有多态性。通过聚类分析计算了各菌株间的遗传距离,并产生树状图,发现同一地区内及不同地区间的病菌表现遗传变异、致病性和DNA多态性间具有一定相关性。  相似文献   

15.
蚜虫内共生菌基因组DNA提取方法的比较和优化   总被引:3,自引:3,他引:0  
为探究蚜虫共生菌基因组DNA的提取方案,以桃蚜为试验材料,比较了目前较为常用的4种蚜虫基因组DNA提取方法,从DNA纯度、完整性、PCR扩增效率及稳定性等方面进行了比较和评价,并通过调整蛋白酶K用量和水浴温度及时间对STE法进行了优化。结果表明,4种方法提取的蚜虫共生菌基因组DNA均可用于共生菌的PCR扩增检测;CTAB法和SDS法提取的DNA纯度较高,条带较完整,稳定性相对较高,不易降解,而STE法和PCR缓冲液法操作简便,适于快速提取单头蚜虫共生菌的基因组DNA,但纯度相对较低;可根据试验条件和要求进行选择。STE法优化条件为:用30 μL STE缓冲液将蚜虫匀浆,加入1.5 μL 20 mg/mL蛋白酶K,于56 ℃水浴1.5 h;再加入0.1 μL 10 mg/L RNA酶,于37 ℃培养1 h,95 ℃下处理5 min,5 000 r/min离心3 min,将提取到的DNA于-20 ℃保存或直接用于PCR扩增。优化后的STE法可作为提取蚜虫共生菌基因组DNA经济而快捷有效的方法。  相似文献   

16.
The cereal root-knot nematode Meloidogyne naasi can cause serious cereal crop losses. The nematode is also found in agricultural fields where non-host crops are grown. Control of M. naasi can be based on preventing its spread, host resistance and crop management as well as on the design of crop rotation systems. Detection methods are required for these purposes and can also be helpful for inspection services and experimental research. This study describes the development of a simple PCR test that enables the detection of M. naasi. Alignment of sequences of rDNA-ITS fragments of M. naasi and five other Meloidogyne species was used to design the M. naasi specific forward primer N-ITS. Together with the reverse primer R195 M. naasi specific amplification was achieved.  相似文献   

17.
果园螟蛾总科部分种类DNA条形码鉴定   总被引:1,自引:1,他引:0  
为检验DNA条形码在鳞翅目螟蛾总科蛾类鉴定中的可行性,对采自山西省太原市晋源区螟蛾总科26种78头蛾类标本分别提取了DNA,扩增了全部78头标本的线粒体cox1基因和其中75头标本的核糖体28S基因,并通过构建系统发育树、计算遗传距离及种间差异阈值等方法,对所有标本进行了鉴定和比较分析,检验了国际DNA条形码数据库BOLD(the barcode of life data)系统的鉴定成功率。结果表明,基于cox1基因和28S基因的系统发育树鉴定成功率分别为100.00%和97.14%,BOLD系统的鉴定成功率达到了67.94%。基于最大简约法、邻接法和最大似然法构建的系统发育树,鉴定结果均相同。基于cox1基因的种内遗传距离全部小于1.00%,种内种间的遗传距离形成明显的3.00%阈值现象。研究表明,cox1及28S基因均适用于供试螟蛾总科种类的鉴定,核糖体28S基因可以作为DNA条形码鉴定的辅助基因;BOLD系统数据库仍有待充实,且标本鉴定工作相对滞后;不同聚类分析方法对结果影响很小,其中邻接法计算速度快,更适合DNA条形码大数据的分析。  相似文献   

18.
To prevent the entry and spread of the brown rot fungus Monilinia fructicola in Europe, a fast and reliable method for detection of this organism is essential. In this study, an automated DNA extraction method combined with a multiplex real‐time PCR based on TaqMan chemistry was developed for fast, convenient and reliable detection of both the EU quarantine organism Monilinia fructicola and the three other brown rot fungi M. fructigena, M. laxa and Monilia polystroma. Using the internal transcribed spacer (ITS) region of the nuclear ribosomal RNA gene repeat, a Monilinia genus‐specific primer pair and two differently labelled fluorogenic probes specific for M. fructicola and the group M. fructigena/M. laxa/Monilia polystroma were developed. The analytical specificity of the assay was assessed by testing 33 isolates of the four brown rot fungi and 13 isolates of related fungal species or other fungal species that can be present on stone and pome fruit. No cross‐reactions were observed. The assay was found to have a detection limit of 0·6 pg of DNA, corresponding to 27 haploid genomes or four conidia. Comparison of a manual DNA isolation followed by a conventional PCR with an automated DNA isolation combined with the presently developed real‐time PCR showed that the latter method gave improved results when tested with 72 naturally infected stone fruit samples. The detection rate increased from 65 to 97%.  相似文献   

19.
 从云南砚山刺茄(Solanum aculeatissimum)上分离到病毒分离物Y322,全序列测定表明,Y322 DNA-A全长2 730个核苷酸,共编码6个ORF。基因组比较发现,Y322 DNA-A与中国番茄黄化曲叶病毒(TYLCCNV)各分离物的同源性最高(88.3%~99.2%),而与其它双生病毒的同源性均在79.6%以下,表明Y322是TYLCCNV的一个分离物。利用DNAβ的特异性引物在Y322中扩增到DNAβ分子(Y322 β),序列分析表明,其全长1 331个核苷酸,与TYLCCNV伴随的DNAβ的同源性最高,达75.1%~93.1%,而与已报道的其它种类的DNAβ的同源性均低于55.4%。这是首次在刺茄中检测到中国番茄黄化曲叶病毒。  相似文献   

20.
在转基因产品检测方法开发、身份鉴定和产品成分定性、定量检测过程中,标准物质是不可缺少的物质基础。本研究对标标准物质申报要求,着重对比了基体标准物质、基因组DNA标准物质、质粒标准物质三种类型转基因检测标准物质的研制过程,提出关键环节的质量控制要求,为促进转基因检测标准物质研制过程标准化、提升研制报告编制质量、提高申报通过率提供技术支撑。  相似文献   

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