Phylogenetic relationships of sect.Nummularia (Lysimachia):evidence from ITS sequences

测定了紫脉过路黄、临时救和过路黄的nrDNA ITS序列,并分析了珍珠菜属过路黄组17个物种的遗传距离及亲缘关系.结果表明,过路黄组植物的ITS序列长度在620～628间,一致性高达90.59%,种间遗传距离为0.002～0.199.系统发育树表明:(1)紫脉过路黄、临时救和小茄亲缘关系较近;(2)大叶过路黄、落地梅和过路黄亲缘关系较近;(3)山萝过路黄、贯叶过路黄、管茎过路黄、叶头过路黄、峨眉过路黄及三角叶过路黄亲缘关系较近.ITS序列分析结果为组内植物的鉴定、分类及系统进化提供了新的参考.     

珍珠菜rDNA ITS序列扩增及分析

以贵州境内珍珠菜属植物为材料,对其rDNA转录间隔区(ITS)序列进行PCR扩增和序列测定。实验共得到7个种的ITS序列,它们分别是:过路黄(Lysi machia christinae,GenBank登录号FJ362382),矮桃(L.cle-throides,GenBank登录号FJ362383),叶头过路黄(L.phyllocephala,GenBank登录号FJ362386),临时救(L.con-gestiflora,GenBank登录号FJ362387),显苞过路黄(L.rubiginosa,GenBank登录号FJ362388),茂汶过路黄(L.stellarioides,GenBank登录号FJ362384),腺药珍珠菜(L.stenosepala,GenBank登录号FJ362385),其中后2个种是国际上首次得到的。采用Blast方法将测序结果进行同源搜索,采用邻接法构建与其相关植物的ITS序列系统发育树。结果表明,珍珠菜属7种植物ITS序列总长度为613~620 bp;ITS1区序列长度为234~239 bp,5.8SrDNA区序列长度163 bp,ITS2区序列长度216~219 bp,7种植物的ITS序列差异主要集中在ITS1与ITS2区。聚类分析将茂汶过路黄聚为一支,其它6种植物聚为一支,表明茂汶过路黄与其它6种植物的碱基差异较大,从分子水平上支持据形态特征把花辐射生长的茂汶过路黄另立一类。     

不同种源何首乌的ITS序列分析及其亲缘关系研究

采用PCR直接测序法,测定了10个种源何首乌的核糖体DNA ITS区序列,并结合GenBank中相关植物的ITS序列(以萹蓄Polygonu maviculare为外类群),应用遗传距离与系统树分析法对不同种源何首乌的亲缘关系进行了分析。结果表明:(1)ITS1序列长度为195bp,G C含量为69.23%~72.31%,ITS2序列长度为189bp,G C含量为77.25%~80.95%,序列间遗传分化距离为0.00175~0.04945;(2)10个种源何首乌构成2个分支,广西田阳种源自成一支,与其它种源亲缘关系较远;(3)结合形态、分布与化学成分,支持将田阳何首乌作为何首乌的一个变种——棱枝何首乌。     

基于ITS序列分析仲彬草属植物的亲缘关系

以旱雀麦为外类群,用PAUP 4.0b10软件并采用最大简约法和邻接法对11份仲彬草属物种的ITS区序列进行系统发育分析,两种方法得到的系统发育树基本一致。结果表明:(1)整个ITS序列长度变异范围为596~601 bp;G C含量在所有ITS中的变化范围为61.20%~62.44%;序列间的遗传分化距离为0.003~0.033,平均值为0.015;(2)疏花仲彬草和塔克拉干仲彬草2个物种聚为一支,位于系统发育树的底部,在最大简约法和邻接法分析中分别获得78%和82%的自展支持率,它们之间的亲缘关系较近;(3)形态相似、地理分布一致的物种有聚在一起的倾向,表现出较近的亲缘关系;(4)ITS区序列分析的结果与细胞学、形态学的研究结果基本一致,因此ITS区序列分析能反映仲彬草属种间关系。     

部分百里香属植物分子系统学研究

采用ITS序列分析和ISSR分子标记技术,对中国野生百里香(5个种2个变种)及国外百里香(2个种)共计20份材料进行了属内种间及种下水平的系统发育和亲缘关系研究.结果表明:(1)ITS序列的系统发育树能较好地说明百里香属种间亲缘关系,地椒、地椒亚洲变种、百里香和Thymus serpyllum共同聚为一组,Bootstrap支持率为96%,表现为较近的亲缘关系;(2)基于ITS序列的系统发育树和ISSR多态性标记的聚类分析均将地椒怀远居群和地椒展毛变种兴凯居群聚为单独的一组,表现出与其它供试材料间较为明显的遗传差异;(3)ISSR遗传多态性分析将地椒、地椒亚洲变种和百里香很好的聚类;种下居群间的聚类则体现了与地理分布之间一定的相关性.将本实验结果与野外考查及形态学比较相结合,可以得出以下结论:地椒、地椒亚洲变种和百里香三者之间属于近缘种,并与国外的T.serpyllum种间有很近的亲缘关系;支持《黑龙江植物志》将地椒展毛变种兴凯居群列为单独的一个种;地椒怀远居群在遗传背景及分布生境上有很大的特殊性,对其在百里香属植物中的系统地位仍需进一步研究确定.     

基于nrDNA ITS序列的广西十大功劳属植物的亲缘关系分析

以广西区6种十大功劳属植物为材料,采用PCR直接测序法测定其nr DNA ITS序列,以Gen Bank中的察瓦龙小檗的序列为外群对照,利用MEGA2.1软件构建7种植物的系统发育树,分析它们的亲缘关系。结果表明:(1)十大功劳属广西区6种植物的ITS序列长度在691~692间,ITS中G+C含量的变化范围为40.52%~42.67%,序列间的遗传分化距离为0.000~0.028,平均值为0.017;(2)NJ、MP、ME聚类树的分支趋势一致,六种十大功劳属植物都聚为一支,都以高支持率(96%以上)将小果十大功劳、阔叶十大功劳和十大功劳聚在一起,然后再和其他3种十大功劳属植物相聚,说明6种十大功劳的亲缘关系都比较近,但小果十大功劳,阔叶十大功劳和十大功劳这3个种的亲缘关系最为密切;(3)在6种十大功劳植物中,分布海拔相同以及分布区域有重叠的种类先相聚,可见这些物种的亲缘关系密切。     

基于ITS序列的东亚当归属植物的分类学研究

采用PCR直接测序法,测定了东亚地区狭义当归属Angelica s.s.及其近缘共7属40种代表植物的核糖体DNA ITS序列,并结合GenBank中相关植物的ITS序列(含外类群3种),应用遗传距离与系统树分析法对东亚地区狭义当归属植物内部以及当归属与其近缘属植物之间的亲缘关系进行了分析。结果表明:(1)广义当归属中的狭义当归属、柳叶芹属Czernaevia和高山芹属Coelopleurum之间的亲缘关系较近,山芹属Ostericum与它们的亲缘关系较远,这与果实形态、化学分析的结果一致,建议将山芹属作为一个相对独立的分类群处理。(2)ITS序列分析结果支持狭义当归属不是单起源的自然分类群,而应该被分成若干组的观点。(3)ITS序列以及化学成分分析结果表明,前胡属Peucedanum与狭义当归属之间的亲缘关系很近。(4)形态、化学成分以及ITS等多方面分析结果显示,当归A.sinensis与狭义当归属的多数植物之间均有一定的差距,其归属问题值得商榷。(5)ITS序列与化学成分的分析结果均显示藁本属Ligusticum不是一个自然类群。     

中国沿海浒苔属rbcL和ITS序列比较及系统进化分析

为阐明中国沿海浒苔的亲缘关系及地理分布特点,采集青岛栈桥、盐城弶港、宁波象山、温州平阳四地浒苔样本,克隆测序得到ITS1、5.8SrDNA和ITS23种不同长度序列片段。四个地区的rbcL目的片段,长度均为1201bp。分析核苷酸差异和遗传距离,采用邻接法建立系统发生树。结果显示,ITS序列进化速率较快,rbcL序列相当保守。ITS区较短,GC含量均在65%以上,5.8SrDNA的CG含量在50%左右,ITS1区的序列差异大于ITS2区。四个地区的浒苔存在一定的地理差异,盐城和青岛的样本间的亲缘关系较近;宁波和温州的样本间的亲缘关系较近。石莼属(Ulva)和浒苔属(Enteromorpha)的物种没有聚成各自独立的分枝,而是相互混合在一起,应是两个亲缘关系相近的属。引起青岛绿潮的海藻很可能是来自盐城海域的Enteromorpha linza或Enteromorpha prolifera。     

不同产区厚朴nrDNA ITS序列分析及亲缘关系鉴定

以陕西、四川、浙江、重庆、福建、广西主产区的11个种源厚朴为材料,采用PCR直接测序法,测定不同产区厚朴的核糖体DNA ITS区序列,并结合GeneBank中相关植物的ITS序列（以同属近缘物种辛夷为外类群）,应用Kimura 2遗传距离与NJ系统树分析法对不同产区厚朴的亲缘关系进行分析。结果表明：11个产区厚朴的ITS全序列长度介于593～600 bp,其中,ITS1长度为214～217 bp,G+C含量为54.42%～5535%,ITS2长度为215～219 bp,G+C含量为59.82%～60.95%;ITS序列共有36个变异位点,均出现在ITS1（7个）和ITS2（29个）序列中,虽然位点变异与部分叶形变化出现吻合,但无必然联系;序列间遗传分化距离为0.000～0.02792,11个产区厚朴构成3个分支,显示出产区间厚朴的亲缘关系,其中陕西洋县（SXYX）、陕西西乡（SXXX）、福建武夷山（FJWYS）及四川彭州（SCPZ）四个产区ITS序列完全一致。nrDNA ITS序列分析可作为厚朴不同产区亲缘关系鉴定的手段。     

基于DNA非编码区序列探讨罗布麻的分类问题

通过测定中国产罗布红麻、大叶白麻和白麻的ITSt、rnL内含子和trnL-F非编码区序列,并与其它相关植物的相应序列比较,探讨“罗布麻”的系统分类。结果显示:罗布红麻、大叶白麻和白麻3种植物的ITS序列完全一致,而与罗布麻属加拿大麻的ITS序列相差较大;在trnL内含子和trnL-F非编码区,大叶白麻和白麻的完全一致,与罗布红麻之间仅有3个位点的变异,而加拿大麻与美国茶叶花在这3个位点却和白麻属的完全一致等。以上结果显示在ITSt、rnL内含子和trnL-F非编码区,白麻属和罗布麻属之间没有本质区别,罗布红麻与大叶白麻和白麻之间的亲缘关系可能较罗布红麻与罗布麻属内其它物种间的亲缘关系更近。遗传距离与系统树的分析结果进一步支持以上推论。建议撤销白麻属,将大叶白麻和白麻合并到罗布麻属。     

珍珠菜属三种植物的核型研究

对国产三种珍珠菜属 (Lysimachia)植物进行了核型研究 ,其中点腺过路黄 (LysimachiahemsleyanaMaxim .)染色体核型 2n =2 2 =2m +4sm +8st+8t,聚花过路黄 (L .congestifloraHesmsl.)核型 2n =2 4=2m +2sm +1 0st+1 0t及山萝过路黄 (L .melampyroidesR .Knuth)染色体数目 2n =2 2 ,核型 2n =2 2 =4m +6sm +4st+8t,为首次报道。本文还分析了黄连花亚属 (subgen.Lysimachia) 2组 8种植物的核型 ,结果表明黄连花组(sect.Lysimachia)核型类型 1A ,过路黄组 (sect.Nummularia)核型类型 3A或 3B。     

不同地理种群美洲斑潜蝇及近缘种的rDNA-ITS1序列分析和比较

【目的】通过对美洲斑潜蝇Liriomyza sativae Blanchard 不同地理种群及近缘种间的核糖体DNA第一内转录间隔区（rDNA-ITS1）进行比较,分析美洲斑潜蝇不同地理种群间的遗传分化情况,并为美洲斑潜蝇与近缘种间提供分子鉴别标记。【方法】用PCR产物直接测序法及克隆测序法对我国美洲斑潜蝇8个地理种群的rDNA-ITS1序列进行测序,并调用GenBank中3个近缘种的rDNA-ITS序列,运用软件MEGA3.1对美洲斑潜蝇不同地理种群及近缘种间的rDNA-ITS1序列进行分析。【结果】美洲斑潜蝇8个地理种群间的分化程度较低,只有8个变异位点,遗传距离都在0.02以下,但4个近缘种间的碱基差异显著,遗传距离为0.149～0.390,有126个变异位点,12个美洲斑潜蝇特异性识别位点。【结论】虽然基于rDNA-ITS1序列所显示的美洲斑潜蝇各地理种群之间的遗传分化很小,但是其分化趋势与地理分布基本相吻合;得到的12个特异性识别位点不仅可以作为美洲斑潜蝇与其近缘种间鉴别的分子标记,而且可为今后设计鉴别性PCR引物提供重要的参考依据。     

Phylogeny and quaternary history of the European montane/alpine endemic Soldanella (Primulaceae) based on ITS and AFLP variation

Soldanella contains 16 species of herbaceous perennials that are endemic to the central and south European high mountains. The genus is ecogeographically subdivided into forest/montane and alpine species. Evolutionary relationships and large-scale biogeographic patterns were inferred from parsimony analyses of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA, and genetic distance analyses based on amplified fragment length polymorphism (AFLP) markers. The ITS region proved useful for examining subgeneric relationships and testing hypotheses on genus-wide divergence times, whereas the AFLP markers were suitable for studying relationships among closely related taxa and biogeographic patterns of divergence. Neither ITS nor AFLP data supported sectional delimitations, particularly those related to the grouping of S. alpina (sect. Soldanella) with S. pusilla (sect. Tubiflores), which may be the result of hybridization. Additional results and conclusions drawn are (1) Soldanella is derived from an ancestor of Asian origin with a montane ecology; (2) estimates of divergence times suggest a late Quaternary origin of the genus; (3) alpine species of sect. Tubiflores diverged from within a paraphyletic sect. Soldanella of mainly montane species; (4) alpine and montane species of Soldanella experienced different cycles of range expansion and contraction during late Quaternary climatic changes, resulting in differential patterns of geographic distribution; and (5) AFLP divergence among montane species from eastern Europe was lower than between alpine species; we hypothesize that the latter differentiated in allopatric regions of expansion during glacials, while the former experienced secondary contact at lower elevations in more southern refugia.     

Sequence Analysis of the ITS Region of Nuclear Ribosomal DNA (nrDNA) in Chinese Amaranthus and Its Systematic Utility

The sequences of the ITS region (including ITS-1, 5.8S rDNA and ITS-2) of nuclear ribosomal DNA from 15 species of the genus Amaranthus L. and outgroup Celosia cristata L. were determined. The result shows that the size of the ITS region of Amaranthus is from 629 to 632 bp, and the length variation is only found in ITS-1 (250-253 bp). On the basis of phylogenetic analysis of nucleotide sequences, the Amaranthus species in China may be devided into three sections, viz., sect. Spinosus, sect. Amaranthus and sect. Paucestamen; the cultivated species, viz., Amaranthus paniculatus L., A. cruentus L., A. caudatus L. and A. hypochondriacus L. can be treated as the subsp. of A. hybridus L.; A. taishanensis F.Z.Li and A. tenuifolius Willd are both closely related to species in the sect. Paucestamen. The study also indicated that the number of stamens has more phylogenetic information than other characters, such as the number of sepals and dehiscence/indehiscence of fruits in Amaranthus.     

5种珍珠菜属植物的核型分析

对 5种珍珠菜属 (LysimachiaL .)植物的核型进行了研究 ,其中巴东过路黄 2n =2x =2 4 =6m 4sm 6st 8t、光叶巴东过路黄 2n =2x =2 4 =6m 4sm 6st 8t、临时救 2n =2x =2 4=2m 4sm 4st 14t的核型属首次报道。过路黄 2n =2x =2 4 =2m 4sm 6st 12t和星宿菜2n =2x =2 4 =2 0m 4sm与前人报道的一致。本文还对该属已报道的 17种植物的核型资料进行了总结和比较分析 ,对珍珠菜属植物的核型进化方向作了初步推测。另外对一存疑过路黄(2n =2x =2 4 =2m 6sm 4st 12t)与其近缘种的核型进行了比较研究。     

Genetic relatedness of Trichoderma sect. Pachybasium species based on molecular approaches

Molecular approaches including internal transcribed spacer (ITS) sequences of ribosomal DNA, universal primer polymerase chain reaction (UP-PCR) fingerprinting, and DNA-DNA hybridization were used to study the genetic relatedness of species within Trichoderma sect. Pachybasium. In the analysis of ITS and 5.8S sequences of ribosomal DNA, parsimony analysis demonstrated that forty-one strains were distributed into five main groups supported by high bootstrap values. The species of Trichoderma sect. Pachybasium were clustered into groups I, II, and IV, with the strains of Trichoderma fasculatum and Trichoderma strictipile forming a separate branch, an independent group V. Some species within each group showed nearly identical sequence differences (fewer than 1-3 bp). UP-PCR and DNA-DNA hybridization were further used to clarify the genetic relatedness of these species with highly similar ITS sequences. Highly similar or identical UP-PCR profiles and high values of DNA complementarity (>70%) were observed among some species, Trichoderma hamatum and Trichoderma pubescens; Trichoderma croceum, Trichoderma polysporum and Trichoderma album, Trichoderma crassum and Trichoderma flavofuscum; and Trichoderma strictipile and Trichoderma fasciculatum. Although every species can be differentiated morphologically, the species showed highly similar molecular characteristics in the above cases, indicating that they could be conspecific. However, in some cases (Trithoderma longipile, T. crassum and T. flavofuscum; Trichoderma fertile and Trichoderma minutisporum; Trichoderma tomentosum, Trichoderma inhamatum and Trichoderma harzianum) there were discriminative patterns of UP-PCR and (or) low levels (<50%) of DNA-DNA hybridization; even their ITS sequences were similar, suggesting a closely phylogenetic relationship.     

韭不同倍性及其非整倍体的ITS序列变异研究

对不同倍性及其非整倍体韭Allium tuberosum和野韭Allium ramosum核糖体DNA的内部转录区(ITS)进行了PCR扩增和克隆,并测定10个ITS1和ITS2的序列,用ITS1 ITS2的序列探讨Allium tuberosum和Allium ramosum的系统发育关系。研究表明,Allium tuberosum与Alli-um ramosum种间的平均Kimura遗传距离仅为0．0146,二者是一对近缘种。虽然韭经历了长期的人工选择和自然选择,但与野韭的分化仍然较小。韭不同倍性及其非整倍体之间,其ITS序列亦无明显差异。     

中国苋属nrDNA的ITS序列分析及其系统学意义

运用ＰＣＲ直接测序法,对苋属（Ａｍａｒａｎｒｈｕｓ Ｌ．）１５个种及外类群鸡冠花（Ｃｅｌｏｓｉａ ｃｒｉｓｔａｔａ Ｌ．）ｎｒＤＮＡ的ＩＴＳ区（包括ＩＴＳ－１,５．８５ｒＤＮＡ和ＩＴＳ－２）进行序列测定。结果表明苋属植物的ＩＴＳ序列总长度为６２９－６３２ｂｐ,长度变异仅发生在ＩＴＳ－１区（２５０－２５３ｂｐ）。采用ＰＡＵＰ软件进行系统发育分析表明：分布于中国的苋属植物可分为３组,即刺苋组（ｓｅｃｇ     

The monophyly and rapid evolution of Gentiana sect. Chondrophyllae Bunge s.l. (Gentianaceae): evidence from the nucleotide sequences of the internal transcribed spacers of nuclear ribosomal DNA

The nucleotide sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA of 24 representative species of sect. Chondrophyllae s.l. have been determined and analysed phylogenetically, together with some species of other sections of the genus Gentiana. The ITS sequences strongly support the monophyly of the sect. Chondrophyllae s.l. as a whole complex including various different dysploid cytotypes. Species, such as G. boryi and G. pyrenaica , that had been split into distinct genera by some cytotaxonomists have been proven to be closely related. However, the ITS sequences do not provide sufficient information to make a robust estimation of the phylogenetic relationships among the closely related species and dysploid cytotypes of the complex, beyond recognizing their monophyly and rapid evolution.     

基于ITS序列探讨山茶属金花茶组的系统发育关系

测定了分布于我国的 2 2个山茶属金花茶组的种或变种的nrDNAITS区序列 ,它们的序列长度在 476～ 496之间。GC含量都超过了 70 % ,应用Kimura2 模型计算了序列间的分化程度 ,构建了最大简约树、邻接树和最大似然树 ,分析结果表明 :( 1 )淡黄金花茶、毛籽金花茶、陇瑞金花茶、弄岗金花茶、大样金花茶和凹脉金花茶的关系较近 ;( 2 )小瓣金花茶、小花金花茶、薄叶金花茶、多瓣金花茶、夏石金花茶和龙州金花茶的关系较近。ITS区序列分析结果与AFLP分析结果相近