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1.
A molecular phylogeny of Hebeloma species from Europe   总被引:2,自引:1,他引:1  
In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.  相似文献   

2.
Taxonomy of the genus Cristulariella is revised, retaining Cristulariella (Crist.) depraedans as the type. Two new species, Crist. cercidiphylli and Crist. corni, are additionally described under the genus. The new anamorphic genus Hinomyces is erected to accommodate Botrytis (Cristulariella) moricola and Cristulariella pruni. A new genus and species, Nervostroma depraedans, is erected in the Sclerotiniaceae to accommodate the teleomorph of Crist. depraedans, with an additional species, Nervostroma cercidiphylli.  相似文献   

3.
Plasmopara penniseti is the sole member of the genus Plasmopara parasitic to Poaceae, after the genus Viennotia had been described to accommodate Plasmopara oplismeni. Morphological, ultrastructural, and molecular phylogenetic data indicate that Plasmopara penniseti is not closely related to the generic type, and it is, therefore, transferred to the newly described genus Poakatesthia. The view that the genera of downy mildews with pyriform to vesicular haustoria (Basidiophora, Benua, Bremia, Paraperonospora, Plasmopara, Plasmoverna, and Protobremia) include species parasitic to Poaceae has to be discarded. All of these genera are apparently restricted to dicotyledonous hosts.  相似文献   

4.
The nuclear ITS region of 19 species of Alnus was amplified and sequenced. The inferred molecular phylogeny shows that all species of the genus Alnus form a monophyletic group close to Betula and that the fundamental dichotomy within the genus lies between the subgenera Alnaster and Gymnothyrsus, sensu Murai (1964). The subgenus Alnaster appears to be basal in the genus, based on archaism of morphological features, and branching close to the root of the trees due to low ITS divergence from genus Betula. The monophyly of the section Clethropsis is not supported by the present data: Alnus nepalensis is positioned in the subgenus Gymnothyrsus, away from A. nitida and A. maritima. Surprisingly, A. formosana sect. Japonicae is closely tied to A. maritima sect. Clethropsis, with which it shares few morphological traits, and is separate from A. japonica sect. Japonicae with which it shares many traits. An increase in substitution rate is noted in the group comprising A. formosana, A. maritima and A. nitida relative to the rest of the genus, which appears to have had, on the average, a very slow mutation rate. Alnus glutinosa, the designated type for the genus, appears to be representative of the genus both for morphological characters and evolutionary rate. North-East Asia is comforted in its position of origin of the genus since not only does it have the highest number of species and representatives in all deep branching lineages, there are also fewer transcontinental migrations when a North-East Asian ancestor is postulated than when a North American ancestor is postulated.  相似文献   

5.
梭菌属分类研究进展:现状和展望   总被引:2,自引:0,他引:2  
目前构成梭菌属的微生物在系统发育和表型特征上不一致。多相分类数据表明,梭菌属物种之间差异大。大量基于16S rRNA 基因的系统发育研究表明,梭菌属应被限定为梭菌属类群I,作为狭义梭菌属(Clostridium sensu stricto)。尽管有这方面认识,梭菌属新物种仍持续增加,这些新物种并不能与梭菌属类群I 和标准种丁酸梭菌(C. butryicum)形成一致分支,引发梭菌属分类上的混乱。本文明确了梭菌属物种的范围,即只包括模式种和梭菌属类群I。此外,4 个物种念珠状真杆菌(Eubacterium moniliforme)、旋舞真杆菌(Eubacterium tarantellae)、最大八叠球菌(Sarcina maxima)和胃八叠球菌(Sarcina ventriculi)应被调至梭菌属,分别命名为念珠状梭菌(Clostridium moniliforme)、旋舞梭菌(Clostridium tarantellae)、最大梭菌(Clostridium maximum)和胃梭菌(Clostridium ventriculi)。一个新属哈撒韦氏菌属(Hathewaya)被提议成立,3 个梭菌属物种溶组织梭菌(Clostridium histolyticum)、泥渣梭菌(Clostridium limosum)和解朊梭菌(Clostridiumproteolyticum)重新归为溶组织哈撒韦氏菌(Hathewaya histolytica)、泥渣哈撒韦氏菌(Hathewaya limosa)和解朊哈撒韦氏菌(Hathewaya proteolytica),其中Hathewaya histolytica 为模式种。  相似文献   

6.
7.
A molecular phylogenetic analysis of Cynoglottis was performed to evaluate previous hypotheses based on non-molecular evidence concerning the position of this genus within Boraginaceae tribe Boragineae. ITS-5.8S and trnLUAA sequences from the nuclear and chloroplast non-coding genomes were obtained for four Cynoglottis taxa and selected members of the related genera Anchusa, Anchusella, Gastrocotyle, Brunnera and Pentaglottis. Cynoglottis is monophyletic, but neither trnL nor ITS support a close relationship with Brunnera, unlike previously supposed on morphological grounds. Brunnera is, instead, related to the southwestern European monotypic genus Pentaglottis, with which it forms a basal clade. ITS-5.8S sequences show that Anchusa thessala, a southeastern European annual species of Anchusa subg. Buglossellum, is sister to Cynoglottis and that the two taxa form a clade which also includes the Balkan endemic Gastrocotyle macedonica. Species of Anchusa subg. Anchusa form a separate lineage with high bootstrap support, suggesting that this heterogeneous genus is paraphyletic with respect to Cynoglottis. ITS sequences also discriminate between the Balkan-Apenninic diploid C. barrelieri and the Anatolian tetraploid C. chetikiana, albeit with low support. The molecular results are discussed in the light of karyological, morphological and chorological aspects.This work has been supported by M.I.U.R. 40% 2003 and the University of Firenze.  相似文献   

8.
The systematic position ofCathaya, a relic genus of thePinaceae, was discussed based on therbcL gene sequence. The sequence data were analysed with PAUP and MEGA programs. The great genetic distance value betweenCathaya and any other genus of thePinaceae showed thatCathaya was a distinct and isolated genus. The most parsimonious Fitch tree and neighbor-joining tree showed thatCathaya was distantly related to the clade comprisingAbies, Keteleeria, Pseudolarix andTsuga, and a sister group relationship betweenCathaya andPinus was weakly supported.Pseudotsuga is closely related toLarix. In theAbies-Keteleeria-Pseudolarix-Tsuga clade,Abies has a close relationship toKeteleeria whilePseudolarix is relatively closely related toTsuga.  相似文献   

9.
首次发现并描述了中国广东省的绣球花科(Hydrangeaceae)常山属(Dichroa)一新种:广东常山(D.fistulosa)。该种具有空心的茎,这在常山属中是唯一的。该种与海南常山(D.mollissima)相似,但可以通过其叶上的毛被来区分。该种亦与菲律宾常山(D.philippinensis)相似,但其叶的形状及锯齿明显不同。  相似文献   

10.
在形态和化学研究的基础上,对中国金黄衣属地衣进行了分类订正。将《中国地衣综览》中微孢衣属的3个种——黄微孢衣、枝瓣微孢衣和戈壁微孢衣正式归入金黄衣属,并分别命名为多孢金黄衣、枝瓣金黄衣和戈壁金黄衣(新拟),并增补散瓣金黄衣(新拟)。至此,中国金黄衣属包括了4个种。该文详细记述了每个种的表型特征和地理分布,并提供了分种检索表。  相似文献   

11.
A new genus of a deep-sea ascomycete with one new species, Alisea longicolla, is described based on analyses of 18S and 28S rDNA sequences and morphological characters. A. longicolla was found together with Oceanitis scuticella, on small twigs and sugar cane debris trawled from the bottom of the Pacific Ocean off Vanuatu Islands. Molecular and morphological characters indicate that both fungi are members of Halosphaeriaceae. Within this family, O. scuticella is phylogenetically related to Ascosalsum and shares similar ascospore morphology and appendage ontogeny. The genus Ascosalsum is considered congeneric with Oceanitis and Ascosalsum cincinnatulum, Ascosalsum unicaudatum and Ascosalsum viscidulum are transferred to Oceanitis, an earlier generic name.  相似文献   

12.
Studies on antagonistic marine actinomycetes from the Bay of Bengal   总被引:3,自引:0,他引:3  
Screening of 26 marine sediment samples near 9 islands of the Andaman Coast of the Bay of Bengal resulted in the isolation of 88 isolates of actinomycetes. On the basis of sporophore morphology and structure of the spore chain, 64 isolates were assigned to the genus Streptomyces, 8 isolates to the genus Micromonospora, 5 to the genus Nocardia, 7 to the genus Streptoverticilium and 4 to the genus Saccharopolyspora. Among 64 Streptomyces spp., 44 isolates showed antibacterial activity and 17 isolates showed antifungal activity. Three isolates showed very promising antagonistic activities against multi-drug resistant pathogens.  相似文献   

13.
Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed  相似文献   

14.
Based on the analysis of 16S rRNA nucleotide sequences, oligonucleotide probes were designed for the detection of representatives of the genus Thermoanaerobacter. To increase the specificity of detection, the genus Thermoanaerobacter was divided into three groups. The probe Tab 827 (5"-GCTTCCGCDYCCCACACCTA-3") detected all known representatives of the genus Thermoanaerobacter; the probe Tab_1 844 (5"-TTAACTACGGCACGRAATGCTTC-3") was specific for the first group of species of the genus (T. wiegelii, T. siderophilus, T. sulfurophilus, T. brockii, T. kivui, T. ethanolicus, T. acetoethylicus, and T. thermohydrosulfuricus); the probe Tab_2 424 (5"-CACTAMYGGGGTTTACAACC-3") targeted the second group (T. thermocopriae, T. mathranii, and T. italicus); and the probe Tab_3 184 (5"-TCCTCCATCAGGATGCCCTA-3") was specific for the third group (T. tengcongensis, T. yonseiensis, T. subterraneus, and Carboxydibrachium pacificum, an organism related to the genus Thermoanaerobacter according to its 16S rRNA sequence). The oligonucleotide probes were labeled with Dig-11-dUTP. Hybridization with the probes showed the affiliation with Thermoanaerobacter of several pure cultures that were morphologically similar to representatives of this genus but possessed metabolic features unusual for it (capacity for agarose hydrolysis, anaerobic oxidation of CO, growth at low pH values) or were isolated from habitats previously unknown for Thermoanaerobacter (deep-sea hydrothermal vents).  相似文献   

15.
本文对彼得黑粉菌属(Franzpetrakia)进行订正研究。此属包括2个种,莠竹彼得黑粉(F. microstegii)和薏苡彼得黑粉新组合(F. okudairae comb. nov.)一对其孢子萌发同物异名及异同点等进行了讨论。彼得黑粉菌属是中国和日本的新记录属。芬竹彼得黑粉是中国新记录种。  相似文献   

16.
In the seventh report of the present series, four species of the genus Pseudocercospora were added to the Japanese mycoflora. They are Pseudocercospora catappae, P. mali, P. polysciatis-pinnatae, and P. puderi.  相似文献   

17.
The aim of this study was to improve our knowledge about the taxonomy and phylogeny of the family Saprolegniaceae, a group of water molds including several pathogens of plants, fish and crustacea. ITS and LSU rDNA were sequenced for representatives of forty species corresponding to ten genera (Achlya, Aphanomyces, Brevilegnia, Dictyuchus, Leptolegenia, Plectospira, Pythiopsis, Saprolegnia, Thraustotheca). Phenetic and cladistic analyses were then carried out. The species Brevilegnia bispora does not appear to belong to the family Saprolegniaceae. Plectospira myrianda clusters with Aphanomyces spp. and they constitute an ancestral group. (Thraustotheca clavata is closely related to the eccentric species of the genus Achlya. The genus Achlya appears polyphyletic, corroborating more or less the three known subgroups, defined by their sexual spore type (eccentric, centric and subcentric). The achlyoid type of spore dehiscence, shared by Aphanomyces and Achlya genera, is shown to be an ancestral character. The saprolegnioid, dictyoid and thraustothecoid types of spore dehiscence are derived characters but their relative evolutionary positions are not resolved.  相似文献   

18.
王文采 《广西植物》2022,42(1):10-13
该文描述了自四川西部发现的毛茛科二新种,包括四川乌头属一新种,即泸定乌头(Aconitum ludingense W.T.Wang),此新种隶属于乌头属乌头亚属,以及四川唐松草属一新种,即狭药唐松草(Thalictrum stenantherum W.T.Wang),给出了此新种与其近缘种六脉萼唐松草之间的形态区别.  相似文献   

19.
20.
王文采 《广西植物》2016,36(1):1-29
(1)根据该文中赤车属与楼梯草属各种形态学的区别,认为赤车属较为原始,在楼梯草属之前自冷水花属衍生而出。(2)将赤车属划分为5组;将C.B.Robinson描述的Elatostemoides属降为组级群,作为赤车属中接近原始群全缘赤车组sect.Pileoides的一个组处理,此外还描述了一个与sect.Elatostemoides近缘的1新组,羽脉赤车组sect.Leiolaena,并根据叶、叶的脉序、雌花序、雌花被片和瘦果等器官的演化趋势给出显示赤车属属下诸群间亲缘关系的系统发育树。(3)对中国赤车属的属下分类群进行了修订,共承认32种1亚种7变种,给出检索表、描述及多幅插图,并将它们划分为4组、2亚组和9系,其中除sect.Leiolaena之外,还新描述了2亚组、5系、2种和3变种;在2003年被归并为同物异名的长柄赤车、曲毛赤车、波缘赤车、小赤车和富宁赤车的种级地位得到恢复。此外,还写出了中国赤车属的分类学简史和地理分布。  相似文献   

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