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1.
本文基于核糖体SSU rDNA序列对石耳科Umbilicariaceae的系统地位进行了研究.将所获得的石耳科地衣中6个种的SSU rDNA序列与GenBank中其它地衣型及非地衣型真菌的相关序列进行比对用于系统发育研究.结果表明长期以来系统地位不够明确而暂时被置于茶渍目Lecanorales的石耳科不能被包括在茶渍目中,分子数据支持成立石耳目Umbilicariales.基于分子数据并结合形态学和解剖学特征描述了新目Umbilicariales J.C. Wei & Q.M. Zhou(Lecanoromycetes,Ascomycota).  相似文献   

2.
有孔虫分子鉴定和分子多样性研究多基于SSU rDNA序列片段分析,但某些浮游种内可能存在基因组内rDNA变化,影响分类学和分子生态学的研究结果。为了研究浮游有孔虫物种内是否存在rDNA多样性,本工作以采自热带西太平洋的浮游有孔虫Globigerinita glutinata活体标本作为研究对象,经形态学鉴定后,利用单细胞PCR和克隆技术,获得5个虫体的20条SSU rDNA目的片段(300—400 bp),同时对其序列结构进行了研究。结果显示,同种G.glutinata出现了四类不同的SSU rDNA核酸类型。序列成对分析显示,该种遗传距离差异最长可达0.249,远高于其它物种。此外,同一样本不同克隆片段中,出现了高达四个不同的SSU rDNA核酸型。序列的差异主要集中在三个不同的高变异区,高可变区的长度范围为21 bp到63 bp。从差异序列的间隔分布推断,核糖体基因簇的重组可能是不同SSU rDNA核酸型出现的原因。本工作在国内首次揭示了热带西太平洋浮游有孔虫G.glutinata种内的SSU rD NA核酸型,研究结果表明G.glutinata的种内SSU rDNA变异性极大,复杂的生活史以及假基因的存在或许是造成该现象的原因。  相似文献   

3.
通过18S rDNA基因(SSU)序列,构建了串珠藻目植物的系统发育关系.结果显示:SSU基因序列片段长度为1 871 bp,核苷酸变异位点有709个,占序列长度的38%;其中简约信息位点有169个,占序列长度的9%.用最大似然法、邻接法和贝叶斯法构建的系统树拓扑结构基本一致,都显示红索藻目的2个属独立于串珠藻目成单独分支,支持红索藻目的建立;胶串珠藻独立于其他串珠藻组植物,支持将其单独分组;数据同时支持将扭曲组和杂生组合并,建立Kumanoa属;但多芒组、绿色组、沼生组等因分子序列数据涉及的种类较少,其系统关系的确定还需要更多的证据.  相似文献   

4.
牛永春  魏江春 《菌物学报》1993,12(Z1):25-29
本文从分子系统学角度为石耳科两个疑难种的分类处理提供了佐证。真菌DNA是从淡腹疱脐衣及露西疱脐衣不含藻细胞的亚茶渍型子囊盘中提取后,用聚合酶链式反应(PCR)技术对于核中核糖体脱氧核酸((rDNA)的转录间区2 (ITS2)片段进行了扩增,并进行了核苷酸序列测定。在分子水平与形态特征以及化学与分布学相结合中进行了比较系统学分析。  相似文献   

5.
研究于2019年冬季对赤水河流域开展刚毛藻多样性调查,共设计采样点38个,覆盖赤水河上、中、下游。调查发现:21个采样位点分布有刚毛藻目藻类,其中19个位点有刚毛藻分布。基于核糖体小亚基(SSU rDNA)、核糖体大亚基(LSU rDNA)和内转录间隔区(ITS)对采集样品进行系统发育分析,结果显示:(1)赤水河流域刚毛藻多样性较高,且该流域上、中、下游均有刚毛藻分布;(2)目前淡水刚毛藻类群包含至少10个支系,赤水河流域采集到的刚毛藻覆盖其中6个支系(分别是clade 1、clade 2、clade 4、clade 7、clade 9和clade 10);(3)相比基于SSU+LSU双分子标记构建的系统进化树,基于SSU+ITS+LSU三分子标记构建的进化树各支系支持度更高,可以较有效地将淡水刚毛藻不同支系区分开来。研究较好地展示了冬季赤水河流域刚毛藻的广泛分布及其分子多样性,丰富了中国淡水丝状绿藻的分类研究,也为赤水河段的水生态环境保护提供了基础数据支持。  相似文献   

6.
研究从中国东海的青石斑鱼 Epinephelus awoara Temminck & Schlegel 1842和褐带石斑鱼E. bruneus Bloch 1793的胆囊中检获了石斑角形虫 Ceratomyxa epinephela Wu, Wu et hua, 1993, 首次提供了其SSU rDNA和ITS1 rDNA序列, 并基于形态学和分子数据进行了重新描述。石斑角形虫成熟孢子的孢子长(4.8±0.5) μm (3.6—5.6 μm), 孢子厚(31.8±4.8) μm (23.3—37.5 μm); 孢子壳瓣光滑且等大, 由垂直的缝线连接; 极囊长(2.9±0.2) μm (2.4—3.7 μm), 极囊宽(2.6±0.2) μm (2.2—3.1 μm); 孢子夹角处稍微凹陷, 延伸至两端逐渐变平坦, 夹角为 (175.9±3.7)° (165.5°—179.7°)。基于SSU rDNA序列构建的系统发育树显示石斑角形虫与诺兰角形虫C. nolani Gunter & Adlard 2009, 卡特莫尔角形虫C. cutmorei Gunter & Adlard 2009和横山角形虫C. yokoyamai Gunter & Adlard 2009 有很近的亲缘关系, 且其宿主均为石斑鱼属物种。结果表明, 类群关系较近的宿主其寄生的同属黏孢子虫可能具有更近的系统发育关系。基于SSU rDNA和ITS1 rDNA的遗传分析显示, 石斑角形虫的4个分离株已发生了明显的遗传分化(形成了4个基因型), 形成了不同的种群, 但在不同宿主种类间并未形成特有的分化。  相似文献   

7.
《菌物学报》2017,(8):1089-1103
本文首先提出了地衣型真菌系统生物学及其3大存取系统是自然界生物多样性与地衣资源研发之间桥梁的概念。其次,以基因型与表型为基础的共同祖征综合分析解决了分子系统学未能解决的石耳科属级分类问题。第三,通过基因型与表型共同祖征的综合分析,发现了边缘种在石耳科属级分化中的存在。对于边缘种的概念进行了具体分析和论述。研究结果表明,石耳科及其各属均为单系类群。  相似文献   

8.
新科Rhizoplacopsidaceae中的新属及新种Rhizoplacopsis weichingii   总被引:3,自引:3,他引:0  
周启明  魏江春 《菌物学报》2006,25(3):376-385
本文描述了位于新科盾叶科 Rhizoplacopsidaceae(Umbilicariales,Lecanoromycetes,Ascomycota)中的新属盾叶属 Rhizoplacopsis 和新种蔚青盾叶 Rhizoplacopsis weichingii。蔚青盾叶取名于著名中国真菌学家王云章教授之字“蔚青”,作为庆祝教授百岁生日之纪念。该新种在外形上与 Rhizoplaca 属地衣极为相似,但位于地衣体上的子囊盘却为网衣型。此外,它的子囊顶器结构非常接近于 Umbilicaria-type。基于分子数据,对 Rhizoplacopsis weichingii 及其它相关地衣进行的系统发育分析支持成立新属盾叶属 Rhizoplacopsis 和新科盾叶科 Rhizoplacopsidaceae。  相似文献   

9.
采用形态分类学方法与以28S rDNA和ITS-5.8S序列为基础的分子系统学研究方法,对采自嘉陵江重庆市磁器口江段的黄颡单尾虫Unicauda pelteobagrusMa,1998进行了形态学和分子生物学的研究。基于28S rDNA数据探讨了黄颡单尾虫以及单尾虫属与相邻种属粘孢子虫间的系统地位;基于5.8S rDNA数据比较分析了粘孢子虫的系统地位。补充了黄颡单尾虫重庆种群形态学信息和28S rDNA、ITS-5.8S rDNA序列的分子信息。  相似文献   

10.
本文结合来自GenBank中的地衣型真菌SSU rDNA中Ⅰ型内含子的相关信息,对取自蜈蚣衣属(Physcia)两个种——斑面蜈蚣衣(Physcia aipolia)、蜈蚣衣(Physcia stellaris),和黑蜈蚣衣属(Phaeophyscia)一个种——毛边黑蜈蚣衣(Phaeophyscia hispidula)共10个样品的SSU rDNA中Ⅰ型内含子的分布模式进行了研究。结果表明,在这些地衣型真菌的SSU rDNA中具有多个Ⅰ型内含子;而内含子插入位点的分布并不具有种的特异性和地理特异性。这种分布模式暗示这些Ⅰ型内含子仍然处于“插入-删除”的平衡状态,而且在此过程中,有性生殖可能比基因的水平转移发挥了更重要的作用。  相似文献   

11.
实验旨在建立牛重组IFN-γ(BovIFN-γ)的ELISA检测技术,为牛传染病的免疫学诊断提供新方法。PHA刺激体外培养的奶牛外周血白细胞,从培养细胞中提取总RNA,经过RT-PCR扩增出BovIFN-γ基因cDNA,进一步克隆至pET28a,转化大肠杆菌,经IPTG诱导,表达出预期大小(18kD左右)组氨酸标记蛋白,经鉴定为BovIFN-γ;以纯化的重组BovIFN-γ为免疫原,应用淋巴细胞杂交瘤技术,获得4株能稳定分泌抗BovIFN-γ单克隆抗体的细胞株,分别命名为A7、A10、G6与G10。免疫球蛋白亚类鉴定证明杂交瘤细胞所分泌的抗体均为IgG1,腹水效价在1∶210×100~1∶211×100之间。Western-blot分析显示,4株单抗均能特异性结合重组BovIFN-γ。ELISA试验表明,4株单抗只与融合蛋白BovIFN-γ反应,而不与非相关性蛋白Ag85B、ESAT-6-CFP-10、GM-CSF等发生反应。选取A10细胞株分泌的单克隆抗体、纯化的多克隆抗体及辣根过氧化物酶(HRP)标记的羊抗兔IgG,建立了检测BovIFN-γ的双抗体夹心ELISA方法。实验结果表明,此方法检测敏感性达到2ng/mL,特异性良好,为进一步建立灵敏、特异的病原感染诊断方法奠定了基础。  相似文献   

12.
张颖  魏江春 《菌物学报》2023,42(2):442-455
生物系统学亦即演化生物学或生物分类学,其目的在于为人类可持续发展中的生物资源研发提供生物信息。以单基因和多基因片段为基础的系统树分析难以获得同一祖先后代的单系类群。同源生物系统学是以共同祖先遗传的基因型和表型为基础进行的分析,是探明单系类群的最佳途径。同源性分析结果表明,石耳亚纲具有一条同源序列S及6种彼此相近的子囊顶器结构,其中包括石耳目以及未定位的5个属。石耳目包括一条同源序列O及石耳型子囊顶器结构。石耳科具有一条同源序列F及脐叶型地衣体。其中疱脐衣属具有一条同源序列L及疱状脐叶体与单孢子囊,石耳属具有一条同源序列U与非疱状脐叶体和八孢子囊。边缘种宾州疱脐衣除具有疱脐衣属同源序列L及疱状脐叶体内含单孢子囊以外,还兼具石耳属同源序列U以及疱狀脐叶体下表偶见气生根;而边缘种卡罗里石耳除具有石耳属同源序列U及非疱状脐叶体内含八孢子囊以外,还兼具疱脐衣属同源序列L以及疱脐衣属特有的砖壁型子囊孢子。  相似文献   

13.
Phylogenetic relationships of lichen-forming discomycetes and their relatives in the class Lecanoromycetes were examined by using nuclear large subunit and mitochondrial small subunit ribosomal DNA sequences. Ninety-eight partial sequences of 53 ascomycetes were generated and aligned with the corresponding sequences retrieved from GenBank resulting in an alignment of 100 taxa that was analyzed using a Bayesian approach with Markov chain Monte Carlo (B/MCMC) methods. The analysis revealed the monophyly of the Lecanoromycetes with two major clades: one clade including the monophyletic orders Graphidales and Ostropales and the paraphyletic Gyalectales, the other clade including the monophyletic Lecanorales (incl. Caliciales, Peltigerales, and Teloschistales) and a clade containing the polyphyletic Agyriales, a yet undescribed order Umbilicariales (including Elixiaceae and Umbilicariaceae), and Pertusariales. The monophyly of the Pertusariales was not resolved. Testing of alternative hypotheses revealed that a placement of Chaetothyriomycetes and Eurotiomycetes within Lecanoromycetes and the monophyly of Agyriales s. lat. (incl. Elixiaceae and Schaereriaceae) and Ostropales s. lat. (incl. Graphidales) can be rejected, while monophyly of Gyalectales and the Pertusariales and placement of Umbilicariales on the Lecanorales branch cannot be rejected with the current data set.  相似文献   

14.
Intrathalline and intracellular chlorophyll concentrations togetherwith thallus structure were studied in 12 species of the lichenfamily Umbilicariaceae in order to explore pigment limitationsfor light absorption and for maximum rates of net photosynthesis(Amax). Species from high light environments tended to haverelatively low chlorophyll concentrations and vice versa. Chlorophyllconcentration on a surface area basis of all species studiedwas sufficient to absorb 80–99% of the incident light,which led us to believe that chlorophyll concentration was nota limiting factor for Amax. Amaxof Umbilicariaceae was smallerthan Amaxof leaves of vascular plants, both on a dry weightand on a surface area basis. These differences slightly decreasedbut did not disappear when referred to the chlorophyll concentrationof the photosynthetic tissues, but reference units had a confoundingeffect in the comparisons. Differences in Amaxon a dry weightbasis between Umbilicariaceae and vascular plants disappearedwhen comparisons were made with the whole plant and not simplywith the leaf. We found a significant, inverse relationshipbetween amount of alga and chlorophyll concentration withinthe algal cells in the lichens studied. This was interpretedas a mechanism to avoid pigment self-shading within the algallayer, distributing more efficiently the photosynthetic pigmentsover a given surface area, and is the first indication of sucha mechanism in lichens. It is suggested that thallus structureand physiology have a larger influence on the observed low Amaxofthe lichens studied than chlorophyll content. Algal cells; chlorophyll concentration; lichens; light harvesting; net photosynthesis; stereology; thallus structure; Umbilicariaceae  相似文献   

15.
The medullary structure of 24 Umbilicariaceae species was studied by light microscopy. The objective was to investigate the variability of the medulla of these lichens and to assess the possible implications for thallus ecophysiology and the taxonomic relevance of the anatomy of this layer. Several methods of embedding, sectioning and staining together with the comparison of radial with transverse sections showed important differences in the degree of cohesion of hyphae and their spatial orientation within the medulla. Other important characteristics were the existence of more than one structurally homogeneous layer within the medulla, the frequency of hyphal branching, the relative thickness of the cell wall and lumen and the abundance of gelatinous matter in the intercellular spaces. The medullae studied were grouped into seven main types. The constancy of the types of medulla for certain groups of species makes it a useful secondary character to be considered in the taxonomy of the Umbilicariaceae. The important role of the structure of the medulla in the water relations of the Umbilicariaceae is discussed and a general relationship between medulla type and hydration strategy is suggested.  相似文献   

16.
L. G. Sancho  L. Kappen 《Oecologia》1989,81(4):473-480
Summary The response of net photosynthesis and dark respiration in eight species of Umbilicariaceae (lichenes) to temperature (-5, 0, 5, 10, 15, 20, 25, 30°C) and irradiance (55, 110, 220, 400, 620 mol photons m-2 s-1 PAR) was studied. The samples were collected in montane and alpine localities of the Spanish Sistema Central. The species differed widely in their net photosynthetic rates. The optimal temperature for net photosynthesis in alpine species was significantly lower than in montane species. Montane species were more photophytic than alpine ones. Water saturation and water loss rate were dependent on morphology and particularly anatomy of the thallus. The physiological and structural data are useful in the interpretation of the ecology and altitudinal distribution of the Umbilicariaceae. No adaptation could be linked to particularities of the mediterranean climate.  相似文献   

17.
中国地衣型子囊菌石耳科纲要   总被引:1,自引:1,他引:0  
魏江春  姜玉梅 《菌物学报》1988,7(Z1):73-106
该纲要为东亚地衣型子囊菌石耳科研究的一部分.对于该科一些种的子囊盘进行了研究.  相似文献   

18.
In the present paper a new species of Lasallia Merat is described and placed under a new subgenus Pleiogyra, characterized by having econcentrical multi-gyrate apothecia. In consequence of this finding, the conception of plane disc in the genus Lasallia of Umbilicariaceae becomes untenable. As a result of careful examination of rich materials, the writer considers the difference in disc found by Scholander among all species of the family is of certain significance for classification. Unfortunately, Scholander’s classification is based solely on this rather variable morphological character. If his view be adopted the new species will have to be inserted into the genus Gyrophora Ach. emend. Schol. If accepting Llano’s division of Umbilicariaceae into five genera, namely Lasallia, Agyrophora, Omphalodiscus, Umbilicaria and Actinogyra, the new species will have to be considered a new genus of the family. The present writer considers both Scholander’s and Llano’s systems as being artificial, because the former author emphasizes too much the unstable morphological appearance of disc and the later simply divides the family into five genera simultaneously on the basis of the stable and unstable characters of the various groups. In contrast with Scholander’s and Llano’s systems Frey’s classification neglects wholly the difference in the characters of disc. Such treatment is likewise unsound. The present writer supports the view held by Flotow, Koerber, Elenkin and Savicz (1950). Nevertheless, he does not agree with Savicz in erecting the subgenus Gyrophoropsis (Elenk. et Savicz) Savicz, because muriform spores are present not only in the group having gyrate discs, but also in the groups having plane and omphalic discs of the Genus Umbilicaria Hoffm. emend. Vej. The recognition of this subgenus must therefore deny the basis on which the other four subgenera are established. The system of Umbilicariaceae held by the writer is as follows: I. Genus Lasallia Merat emend. Vej ...... Thallus pustulate; disc plane to econcentrical multi-gyrate; spores 1(2) per ascus, quite large, muriform. 1. Subgenus Lasallia...Disc plane. 2. Subgenus Pleiogyra Vej ...... Disc econcentrical multigyrate. II. Genus Umbilicaria Hoffm. emend. Vej (syn. Gyrophora Ach. emend. Savicz)* ...Thallus non-pustulate; disc plane and smooth or plane with central sterile column (or fissure) or with gyri; spores 8 per ascus, simple, hyaline or becoming brown muriform, small. 1. Subgenns Agyrophora (Nyl.) Savicz ...... Disc plane. (1) Section Agyrophora (syn. sect. Anthracinae emend. Llano). ..... Spores simple and hyaline. (2) Section Dichroae Llano ...... Spores becoming brown muriform. 2. Subgenus Omphalodiscus (Schol.) Savicz ...... Disc with central sterile column or fissure. (1) Section Omphalodiscus (syn. sect. Decussatae Schol.) ...... Spores simple and hyaline. (2) Section Spodochroae Schol. ..... Spores becoming muriform. 3. Subgenus Umbilicaria...Disc with concentrical gyri; spores simple and hyaline or becoming muriform. (1) Section Umbilicaria (syn. sect. Simplices Llano) ...... Spores simple and hyaline. (2) Section Gyrophoropsis (Elenk. et Savicz) A. Zahlbr. (syn. sect. Muriformes Llano) ...... Spores becoming muriform.4. Subgenus Actinogyra (Schol.) Savicz ...... Disc with radial gyri, proper margin absent.  相似文献   

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