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1.
《Hydrobiologia》1990,193(1):275-278
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The genera Leucothrix and Thiothrix   总被引:11,自引:0,他引:11  
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Aerial parts of Gonospermum fruticosum collected at several locations in the Canary Islands afforded, in addition to known compounds, four sesquiterpene alcohols related to costol and a sesquiterpene lactone, whose structures were established on the basis of their spectroscopic data and chemical transformations. Except for Gonospermum species collected on the island of Tenerife, those collected on the island of El Hierro and, in a previous study those from La Gomera, contain sesquiterpene lactones that can be used as chemotaxonomic markers confirming the inclusion of Gonospermum, Lugoa, and species of Tanacetum endemic to the Canary Islands in a genus that does not support the monophyly of Gonosperminae.  相似文献   

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Molecular phylogeny of Trametes and related genera   总被引:1,自引:0,他引:1  
Mitochondrial small subunit ribosomal DNAs were sequenced and phylogenetically analyzed for Trametes and related genera of Ryvarden's Trametes group. Parsimony and distance analyses indicated that most of trimitic genera with white rotting habit of the Trametes group clustered within a single clade, suggesting that they may have originated from a common ancestor. The phylogenetic position and generic placement of Trametes consors was uncertain as yet. Trametes trogii grouped with Coriolopsis gallica and indicated that color of the basidiocarp is a poor character at generic level. Nucleotide differences between Daedaleopsis confragosa and D. tricolor were quite few and both species closely grouped together in a same clade, thus supporting that D. tricolor might be an ecotype of D. confragosa.  相似文献   

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芸薹属A,B和C基因组之间关系研究进展   总被引:4,自引:0,他引:4  
栗茂腾  张椿雨  刘列钊  余龙江 《遗传》2005,27(4):671-676
芸薹属A,B和C基因组之间的亲缘关系近年来取得了很大进展,大量细胞遗传学和分子生物学的研究结果表明A和C基因组之间的亲缘关系较A和B基因组以及B和C基因组之间更为接近。A,B和C基因组之间的比较基因组结果表明,这3个基因组是由更加原始物种进化而来的。在芸薹属基因组演化过程中发生了大量的染色体变异,如重复、缺失、重排等,从而造成了现在不同基因组之间的差别。最后,文章对芸薹属不同基因组和拟南芥基因组之间的亲缘关系进行了综述。  相似文献   

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We used maximum likelihood analysis of complete mitochondrial ND2 sequences (1041 bp) to clarify the taxonomy and relationships of various species and genera of grass and bush warblers. The tree revealed two clades of grass and bush warblers. One clade was comprised of all four western Palearctic Locustella and two species of Asian Bradypterus . The other clade included five eastern Palearctic Locustella (including the distinctive Sakhalin warbler Locustella amnicola ) and the marsh grassbird Megalurus pryeri . African Bradypterus and Australian little grassbird Megalurus gramineus were distantly related to their Asian congeners. Therefore, current taxonomy of these genera does not reflect their evolutionary history and needs revision. It is proposed that a phylogenetic analysis of morphology and ecological preferences would show that the current taxonomy of grass and bush warblers reflects species' habitat preferences and morphology related to locomotion and foraging in their habitats, rather than their shared ancestry. Distinct clades were found in grasshopper warbler Locustella naevia and Pallas's grasshopper warbler L. certhiola . Detailed phylogeographic studies are needed to elucidate the species status of the clades within these two species.  相似文献   

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The classification ofAthyrium sensu lato is revised on the basis of evidence from anatomical and morphological observations. Although parallelism is found in several characteristics, stipe base, groove of frond axis, laminar margin, venation, sorus and dermal appendage are important to classify the genus and elucidate the relationship within it.Athyrium sensu lato is divided into four generaAthyrium, Cornopteris, Deparia andDiplazium, small genera being referred toAthyrium orDiplazium, Deparia is construed in a broad sense to includeAthyriopsis, Dryoathyrium andLunathyrium. The four genera with infrageneric groups or sections are described in detail. Among the genera,Athyrium, particularly theA. puncticaule group, may be considered to have primitive characteristics, andCornopteris may have been derived fromAthyrium by abortion of the indusia.Cystopteris is also related toAthyrium on the basis of reniform sori inC. douglasii.  相似文献   

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Two glossoptcrid fructifications from the Permian are described. Mudgea , from Australia, consists of a tuft of scales bearing winged orbicular seeds and Breytenia is an urceolate receptacle with biconvex ovules.  相似文献   

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Problems presented by genera, or small groups of genera, which have been given family rank are reviewed, and the genera are divided into a number of categories according to the closeness of their affinity to other genera or families. Satellite genera that stand in close relation to families should be united with them. Binary families, that have been divided into two (or more) related families, should be re–united. Families connected by linking genera, should, logically, be united but practical considerations usually prevent this. Clusters of diverse but more or less distantly related genera present unusual problems, being treated either as several, often monogeneric families or as a loosely structured family. Truly isolated genera must be given family and often ordinal rank.  相似文献   

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Exoantigens from Erynia neoaphidis, Conidiobolus major, C. thromboides, C. obscurus, Zoophthora radicans, and Basidiobolus ranarum were obtained from culture filtrates of fungal material grown in a yeast extract, peptone dialysate, dextrose medium and were tested against specific hyperimmune antisera prepared from E. neoaphidis, C. major, C. thromboides, and B. ranarum by the immunodiffusion technique. Specific precipitins were observed for E. neoaphidis and B. ranarum, while cross-reactions were detected among C. major, C. thromboides, and C. obscurus. The results suggest that genera of Entomophthorales can be easily separated by this simple immunological procedure.  相似文献   

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Hamana K  Itoh T 《Microbios》2001,104(408):105-114
Cellular polyamines of eight new thermophilic archaebacteria were investigated to determine the chemotaxonomic significance of polyamine distribution profiles. Hyperthermoacidophilic Caldivirga maquilingensis belonging to the family Thermoproteaceae of the Crenarchaeota have a unique polyamine profile comprising spermidine, norspermidine and norspermine as the major polyamines. Within the order Thermococcales of the Euryarchaeota, the major polyamines of an extremely thermophilic terrestrial species of Thermococcus, T. zilligii, were spermidine and agmatine, whereas hyperthermophilic submarine species of Thermococcus and hyperthermophilic submarine Palaeococcus ferrophilus contained a quaternary branched penta-amine, N4-bis(aminopropyl)spermidine, as a major polyamine. A hyperthermophilic methanogen, Methanothermus sociabilis, belonging to Euryarchaeota, contained spermidine and spermine as the major polyamine.  相似文献   

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The taxonomy of the genera Moraxella and Neisseria   总被引:7,自引:0,他引:7  
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Hsieh HM  Ju YM  Rogers JD 《Mycologia》2005,97(4):844-865
Phylogenetic relationships were inferred among several xylariaceous genera with Nodulisporium or nodulisporium-like anamorphs based on the analyses of beta-tubulin and alpha-actin sequences. One hundred nine cultures and three specimens of 83 representatives of these four genera were included in the study. Biscogniauxia taxa formed a well supported clade that was basal to the other taxa, while taxa of Hypoxylon and Daldinia comprised a large monophyletic group that contained two subclades. The first subclade encompassed Hypoxylon sect. Annulata and is accepted here as the new genus Annulohypoxylon. The second subclade contained taxa of Hypoxylon sect. Hypoxylon and Daldinia. Hypoxylon is restricted to include only those taxa in sect. Hypoxylon. Thirty-three epithets are made in Annulohypoxylon. Hypoxylon cohaerens var. microsporum is raised to the species level and accepted as A. minutellum. Hypoxylon polyporoideum is recognized as distinct from H. crocopeplum. Hypoxylon placentiforme is accepted as Daldinia placentiformis.  相似文献   

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