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41.
亚洲部分地区东方蜜蜂mtDNA多态性研究   总被引:1,自引:0,他引:1  
 就云南省7个不同样点共7群东方蜜蜂蜂群开展mtDNA内切酶位点测试和分析研究,并与菲律宾的东方蜜蜂作对比分析。内切酶DraI分析7个蜂群,共发现4个内切酶位点;云南东方蜜蜂mtDNA的tRNAleu-COII基因的序列没有长度多态性,EcoRI内切酶位点共有4个,与菲律宾的吕宋岛的东方蜜蜂属于同一单倍型。另外,对来自尼泊尔、泰国、越南、老挝以及我国北京、云南等地的共13群蜜蜂mtDNA COII基因的420个碱基对进行测序分析,发现13群东方蜜蜂分析的420个碱基序列里,位点变异从0个到5个不等,变异率从0到1.19%. 用邻接法(neighbor-joining)构建的分子系统树可以看出分枝树主要分为两个类群:高纬度或高海拔的蜂群为一个类群,它们主要来自撒营盘(2)(China 4)、丽江(China 7)、北京(1)(China 1)、尼泊尔(Nepal)、北京(2)(China 2)、河口(1)(China 8)和越南(2)(Vietnam 2)。另一个类群的主要来自低纬度或低海拔的蜂群,它们主要来自撒营盘(1)(China 3)、景洪(China 5)、越南(1)(Vietnam 1)、泰国(Thailand)、河口(2) (China 6)和老挝(Laos)。该实验为我国东方蜜蜂资源的保护和开发研究提供了重要的信息和手段。  相似文献   
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Corispermum is one of the most problematic taxonomic genera in Chenopodiaceae.To understand the phylogeny and infrageneric variation of Corispermum,we sequenced the nuclear ribosomal ITS region and two chloroplast DNA regions(rbcL and psbB-psbH) of 22 species and three varieties of Corispermum and the related genus Agriophyllum.Several representative species of Salsola,Suaeda,Chenopodium,Kalidium and Camphorosma served as outgroups.Our phylogenetic trees confirm that the tribe Corispermeae is monophyletic,Corispermum and Agriophyllum have a close relationship.Corispermum is demonstrated to be monophyletic,and contains at least four clades which,consequently,are served as the foundation of the infrageneric sectional variation of Corispermum,in terms of a combination of molecular data and morphological characters.The evolution of morphological characters for fruit wing and apex,two important characters in generic classification,is consistent with the sectional division of Corispermum,especially to the East Asian and Chinese taxa.  相似文献   
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The RFLP technique has been employed to investigate phylogenetic relationships between species of the Hedysarum genus. Homologous DNA probes were used to generate patterns from a set of the Mediterranean group. The degree of band sharing was used to estimate genetic distances between species and to draw phylogenetic trees. These are in good agreement with phylogeny based on morphological and isozyme markers, but contain novel insights. The results are discussed in the context of current work in molecular biosystematics in Hedysarum complex. Attempts made in this approach to access the extent of variability at the DNA level occurring with the domestication process have been investigated. With the availability of the tested probes, it has been assumed that the genetic structure is not affected by the domestication process.  相似文献   
46.
弯翅蠊亚科Panesthiinae (蜚蠊目:硕蠊总科)为一类钻蛀朽木生活的木食性蜚蠊(wood-feeding cockroaches),是森林生态系统中重要的分解者,主要分布在澳洲、马来-印尼群岛以及东南亚等热带亚热带地区.该亚科分类学研究多数为早期的形态学研究,近年有少数新种利用现代分子技术进行研究.NCBI网站共提交了弯翅蠊亚科59个分类单元,194条核苷酸序列.该亚科分子系统发育学方面已有较丰富的研究,主要用于推断属间和种间进化关系和亲缘关系,同时根据这些分子证据进行谱系地理学研究,推断弯翅蠊亚科昆虫的种群扩散和生物入侵时间和方式,侧面猜测地理历史事件.另外,分子研究报道了一些弯翅蠊亚科体内的内共生物,并深入进行了协同进化等方面的研究.展望了新技术方法在弯翅蠊亚科分子研究中的应用.  相似文献   
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Apple mosaic virus (ApMV, genus Ilarvirus) was detected in pears, a previously non-reported virus host. No symptoms were visible on the hosts leaves. Seventeen out of 22 randomly selected pear trees in Italy (Lombardy) and in three regions in the Czech Republic were ApMV-infected. All nine newly sequenced ApMV isolates from pears had a 15-nucleotide insertion in the capsid protein gene in identical position of that of apple isolates compared with isolates from hop and prunes. The insertion is the most prominent (but not essential) modification of the capsid protein gene, which results in a phylogenetic separation of ApMV isolates into three clusters. Sequence analysis data of an additional 15 isolates revealed a sequence correlation with kernelled fruit trees (apple and pear).  相似文献   
49.
The study aimed to explore the phylogeny and genetic diversity of 3 hare species in Xinjiang by molecular genetics methods, define the relationship and taxonomy status, assess diversity level of Lepus in Xinjiang, and provide the basic data for conservation genetics of hares in Xinjiang and even in China. Three mitochondrial DNA genes, COI, ND4 and 16S rRNA, were used as molecular markers, and the sequences of 3 genes of 57 samples collected from 8 different regions (4 geographic groups) in Xinjiang were determined by PCR amplification and sequencing technology. After the sequences of COI, ND4 and 16S rRNA of each sample were revised and pooled together, data were analyzed with softwares such as MEGA 7, DNAsp 6, Arlequin 3.1 and MrBayes 3.2. A total of 43 haplotypes were detected from the combined sequences of 3 genes of 57 hare samples. Five distinct clades (A-E) and 3 clusters were clearly showed in phylogenetic tree and median-joining network (MJN). Furthermore, the genetic distance between 3 clusters reached the level of species (4.21%-9.09%). However, the genetic distance between hares from northern Xinjiang (Clade E) and those from central Xinjiang (Clade D) were not up to the level of species (≤2.26%) in the third cluster. The haplotype diversity (h) of Lepus yarkandensis, Lepus tibetanus pamirensis and Lepus tolai lehmanni were higher(0.979±0.014, 0.972±0.064 and 0.972±0.064, respectively), while the nucleotide diversity (π) of the L. t. lehmanni and L. t. centrasiaticus were higher (0.033±0.018 and 0.023±0.015, respectively). Based on comprehensive analysis of 3 genes of mitochondrion and reference with published research, it is suggested that hares from southwestern Pamir Plateau of Xinjiang should belong to L. t. pamirensis. Meanwhile,hares distributed in northern and central Xinjiang might be considered as L. t. lehmanni and L. t. centrasiaticus. Moreover, there is abundant genetic diversity in the 3 hare species in Xinjiang, and the obvious phylogeographic pattern is showed.  相似文献   
50.
以黄花软紫草(Arnebia guttata Bunge)和双柱紫草(Coldenia procumbens L.)为外类群,用PAUP*4.0 对鹤虱属(Lappula Moench)13个代表种的核糖体ITS和叶绿体rpS16序列进行分子系统发育分析。采用最大简约法和最大似然法对获得的序列矩阵进行分析,得到一致性进化树。拓扑结构显示,Lappula为单系类群,前人对该属属下阶元的划分带有一定的人为主观性,不能完全真实反映其系统发育关系。结合形态学特征,得出该属植物大致沿着花由小型到大型,果实由同型到异型,小坚果边缘有瘤或刺到具翅这样的路线演化的。  相似文献   
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