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1.
Recent taxonomical revisions based on multilocus gene sequencing have provided some clarifications to dermatophyte (Arthrodermataceae) family tree. These changes promoted us to investigate the impact of the changed nomenclature of the dermatophyte strains in the BCCM/IHEM fungal collection, which contains strains of all dermatophyte genera except for Ctenomyces. For 688 strains from this collection, both internal transcribed spacer region (ITS) and partial β-tubulin (BT) sequences were aligned and a multilocus phylogenetic tree was constructed. The ITS?+?BT phylogentic tree was able to distinguish the genera Arthroderma, Lophophyton, Microsporum, Paraphyton, Nannizzia and Trichophyton with high certainty. Epidermophyton, which is widely considered as a well-defined genus with E. floccosum as the only representative, fell within the Nannizzia clade, whereas the phylogenetic analysis, based on the ITS region alone, differentiates Epidermophyton from Nannizzia as a separate genus. Re-identification and reclassification of many strains in the collection have had a profound impact on the composition of the BCCM/IHEM dermatophyte collection. The biggest change is the decline of prevalence of Arthroderma strains; starting with 103 strains, only 22 strains remain in the genus after reassessment. Most Arthroderma strains were reclassified into Trichophyton, with A. benhamiae and A. vanbreuseghemii leaving the genus. The amount of Microsporum strains also dropped significantly with most of these strains being reclassified into the genera Paraphyton and Nannizzia. 相似文献
2.
A new species of Nectria, N. palmicola on rachides of Mauritia flexuosa, is described from Ecuador. It is compared with the similar species. N. calami and N. pseudopezizia. Nectria palmicola is illustrated with light and SEM micrographs and line diagrams. A key and host index to species of Nectria and allied genera on palms is given. 相似文献
3.
During a survey fungal diversity of xylariaceous fungi in Thailand, a new Nemania species, N. plumbea, was identified. Nemania plumbea is characterized by soft-textured grey stromata on a persistent mat of white hyphae, pale brown ascospores with a short germ-slit on the more convex side. It also produces a Geniculosporium-like anamorph in culture. In order to evaluate its phylogenetic relationships among related species and genera, ITS-5.8S rDNA and RPB2 were analysed separately and simultaneously. Results from the phylogenetic analyses indicate that there is close phylogenetic association between N. plumbea and N. aenea. A preliminary account into the natural grouping of Xylariaceae based on ITS-5.8S rDNA and RPB2 sequences is also discussed. 相似文献
4.
Molecular data were used to evaluate the validity of the genus Neopisosoma Haig, 1960. Comparisons of morphological features within Neopisosoma suggest the existence of two lineages, represented among others, by N. angustifrons (Benedict, 1901) and N. neglectum Werding (1986). Both lineages of Neopisosoma are more similar to two morphologically different species groups of the genus Pachycheles, than to congeners of the other group. Comparative morphology of larvae from N. angustifrons, N. neglectum and species of Pachycheles shows that N. angustifrons closely resembles Pachycheles species, whilst N. neglectum is set apart. Sequences of a 465 bp segment of the mitochondrial gene cytochrome oxidase I (COI) were obtained and used to infer phylogenetic relationships among N. angustifrons, N. neglectum, one species of Pachycheles and seven other species of porcellanids, representing three other genera. Results of the molecular analysis were congruent to results of comparative morphological studies of larvae: N. angustifrons grouped with the Pachycheles species, whereas N. neglectum is placed apart. This led us to the conclusion that the genus Neopisosoma is probably paraphyletic and that the criterion used by Haig (1960) is not reliable to define the genus. A revision on a world-wide basis of the genera included, and additional sequence information will be necessary to satisfactorily resolve relationships within the Porcellanidae. 相似文献
5.
Substantial enrichment of some plant parts in 15N relative to the rest of the plant is unusual, but is found in the nitrogen-fixing nodules of many legumes. A range of actinorhizal plants was surveyed to determine whether the nodules of any of them are also substantially enriched in 15N. The nonlegume Parasponia, nodulated by a rhizobium, was also included. Four of the actinorhizal genera and Parasponia were grown in N-free culture, and three actinorhizal genera were collected from the field. Nodules of Parasponia, Casuarina and Alnus were 15N enriched relative to other plant parts, but only Parasponia approached the degree of enrichment found in some legume nodules. The nodules of Datisca, Myrica, Elaeagnus, Shepherdia, and Coriaria were depleted in 15N. Thus many actinorhizal nodules are depleted in 15N compared to other plant parts and enrichment is modest when it does occur. Whole plant 15N content ( 15N) in four actinorhizal plants and Parasponia showed a relatively narrow range of –1.41 to –1.90. Hence regardless of the degree of nodule enrichment or depletion, whole plant 15N content appears to vary little in plants grown in N-free culture. 相似文献
6.
本文系作者继大戟属( Euphorbia L.)、守宫木属( Sauropus B1.)和铁苋菜属( Acalypha L.)植物上链格孢属( Alternaria Nees)真菌研究(Zhang, 1995)之后,对生于大戟科( Euphorbiaceae)其它属植物上一些链格孢真菌种级分类单位评鉴结果的后续报道.内容包括:一个新种,巴豆生链格孢(A. croronicola T. Y.Zhang & J. C. David), Macrosporium compactum Cooke:对其模式标本(holotype)进行T订正、巴豆链格孢[ A.crotonis kamal,Singh & Kumar]:提出关于新模式(neotype)标本的建议;对蓖麻链格孢[ A. ricini(yoshii)Hansford]典型性状作了补充描述.此外,还在大戟科其它一些植物上检查到长极链格孢[ A. longissima Deighton et MacGarvie]和细极链格孢[ A. tenuissima(Nees ez Fr.) Wiltshire]。 相似文献
8.
Meiotic chromosome numbers are reported for 12 species in eight genera of Acanthaceae from Madagascar. Chromosome numbers
of 11 species are reported for the first time. Counts in Mendoncia ( n=19) and Neuracanthus ( n=20) are the first for these genera. A new chromosome number ( n=30) is reported in Justicia. Systematic implications of the chromosome counts are addressed and basic chromosome numbers for these eight genera of Malagasy
Acanthaceae are discussed. 相似文献
9.
Phosphate-independent nucleoside deoxyribosyltransferase activity was detected in Aerococcus viridans, Leuconostoc mesenteroides, two species of Pediococcus, eight obligately homofermentative and three obligately heterofermentative lactobacilli. In cellfree extracts of one strain of Lactococcus, one strain of Streptococcus and three strains of facultatively heterofermentative lactobacilli no phosphate-independent nucleoside deoxyribosyltransferase could be detected and inosine nucleoside phosphorylase was the only enzyme catalysing pentosyl transfer to purines. A classification based on the presence or absence of these enzymes separates Streptococcus and Lactococcus from the remaining genera which is in agreement with studies using anti-aldolase sera and 16S rRNA oligonucleotide catalogues.Abbreviations NCIMB
National Collection of Industrial and Marine bacteria
- NCDO
National Collection of Dairy organisms
- MRS
deMan Rogosa Sharpe
- Pipes
Piperazine- N,N-bis[2-ethanesulphonic acid] 相似文献
10.
Aralia, described by Linnaeus, remains a poorly defined genus. Many satellite genera of Aralia have been proposed, and some have been accepted without critical evaluation. These genera include Coudenbergia, Megalopanax, Parapentapanax, and Pentapanax. This study examined the historical background of the establishment of these genera and their diagnostic characters. It was
found that (1) Aralia s. str. is a relatively diverse genus; (2) the separation of Pentapanax and Parapentapanax from Aralia is unsubstantiated; (3) Megalopanax is synonymous with Coudenbergia; and (4) the boundaries between Aralia and both Coudenbergia and Pentapanax intergrade. It is proposed, therefore, to merge Coudenbergia, Parapentapanax, and Pentapanax with Aralia, which has nomenclatural priority. Aralia is herein defined as consisting of those species in Araliaceae with pinnate leaves, articulated rachises, five to eight-merous
flowers, petals imbricate in buds, and articulated pedicels. The revised generic concept requires the following new combinations
or new names: Aralia castanopsisicola, A. franchetti, A. gigantea, A. laevis, A. leschenaultii, A. parasitica, A. rex, A. subcordata, A.
verticillata, and A. warmingiana. 相似文献
11.
The tribe Plucheeae ( Benth.) A. Anderb., has been analysed cladistically by means of a computerized parsimony program (Hennig 86), using the Arctotideae as outgroup. The results of the analysis are presented in a consensus tree and one cladogram. Four major monophyletic subgroups can be recognized: The Coleocoma group (3 genera), the Pterocaulon group (3 genera), the Laggera group (6 genera), and the Pluchea group (12 genera). All recognized genera are described and most genera are supplied with taxonomical notes including comments on their taxonomic status. Genera such as Blumea, Pluchea, and Epaltes are demonstrated to be unnatural assemblages. Monarrhenus and Tessaria are both closely related to the Pluchea complex. The old generic name Litogyne
Harv. has been taken up for one species of Epaltes, the genus Rhodogeron is reduced to a synonym of Sachsia, and the following new combinations are made; Litogyne gariepina (DC.) A. Anderb., and Sachsia coronopifolia ( Griseb.) A. Anderb. 相似文献
12.
The seed morphology of 79 species of neotropical Miconieae (Melastomataceae) is presented. These species have been chosen,
in majority, from the polyphyletic genus Leandra. A few other species from the polyphyletic genera Miconia, Ossaea, and Clidemia were also sampled, because of potential similarities. Sixteen morphological seed types are defined after analysis through
light microscopy and scanning electron microscopy. The seed morphology appears to possess a great deal of variability on the
level of the overall shape as well as the structure and the surface of the testa. The different types defined here do not
match with genera or sections, but rather are composed of species coming from different genera. In comparison with a preliminary
molecular phylogeny study done on Leandra, some types of seeds are related to well supported clades. In some cases seed morphology corresponds with natural groups
of species, thus being of high phylogenetic importance. 相似文献
13.
广义无心菜属(Arenaria L.s.l.)是石竹科(Caryophyllaceae)中分类较为困难的大属之一,基于分子系统学研究结果该属目前已被拆分为多属.基于形态学证据,桃色无心菜(Arenaria melandryoides Edgew.)被置于无心菜属齿瓣亚属[subg.Odontostemma(G.Don)... 相似文献
14.
The taxonomic positions of the marine genera Alteromonas, Pseudoalteromonas, Idiomarina, and Colwellia within the gamma subclass of the class Proteobacteria were specified on the basis of their phenotypic, genotypic, and phylogenetic characteristics. Gram-negative aerobic bacteria of the genera Alteromonas, Pseudoalteromonas, and Idiomarina and facultatively anaerobic bacteria of the genus Colwellia were found to form a phylogenetic cluster with a 16S rRNA sequence homology of 90% or higher. The characteristics of these genera presented in this paper allow their reliable taxonomic identification. Based on the analysis of our experimental data and analyses available in the literature, we propose to combine the genera Alteromonas, Pseudoalteromonas, Idiomarina, and Colwellia into a new family, Alteromonadaceae fam. nov., with the type genus Alteromonas. 相似文献
15.
Paraveinal mesophyll (PVM) is a distinctive anatomical feature of the leaf mesophyll of some plant taxa that may represent a specialized physiological compartment. A comprehensive review of the 42 published references that mention PVM or similar cell layers and a survey of 121 of the 272 species of all nine genera of the Phaseoleae subtribe Erythrininae demonstrate that PVM is nearly exclusively found in Leguminosae. In Leguminosae, PVM is either rare or absent in subfamily Caesalpinioideae, uncommon in Mimosoideae, and extensively distributed among Papilionoideae. In subtribe Erythrininae, PVM is ubiquitous in Erythrina, and occurs in four other genera. Three Erythrininae genera ( Apios, Mucuna, and Cochlianthus) lack PVM. Unique chloroplast-poor, enlarged conical cells (pellucid palisade idioblasts) occur in 80 species of Erythrina but not in any other genus of Erythrininae. 相似文献
16.
Noctiluca scintillans food vacuoles containing toxigenic microalgae of the genera Dinophysis and Pseudo-nitzschia are reported in samples from the Galician Rías Baixas (NW Spain). N. scintillans may play an important role in the population dynamics of toxigenic microalgae blooms, and may act as a vector of phycotoxins to higher trophic levels. The harmful effects of Noctiluca in natural shellfish beds and/or aquaculture sites may be magnified if cells are loaded with toxigenic microalgal prey. 相似文献
17.
为研究夹竹桃(Nerium oleander)内生真菌的多样性并评价其次生代谢产物的活性,该研究对广西夹竹桃(Nerium oleander)的内生真菌进行分离纯化,采用形态学和ITS序列分析结合的方法进行鉴定,以5种指示菌(其中有3种弧菌)对内生真菌提取物进行抑菌活性筛选。结果表明:(1)从广西夹竹桃中共得到19株内生真菌,这19株内生真菌都属于子囊菌门,涵盖5个目7个属,包括炭疽菌属(Colletotrichum)、球座菌属(Guignardia)、叶点霉属(Phyllosticta)、新壳梭孢属(Neofusicoccum)、曲霉属(Aspergillus)、隔孢壳科新属(Nothophoma)和间座壳属(Diaporthe),优势属为炭疽菌属(分离率为36.85%)和球座菌属(分离率为21.05%),其中炭疽菌属主要分布于茎,球座菌属全部来源于叶。(2)jing-117(Neofusicoccum sp.)和ye-130(Guignardia sp.)对坎氏弧菌有较为特异的抑菌效果,ye-136(Aspergillus sp.)能同时抑制蜡样芽孢杆菌和坎氏弧菌,ye-135(A... 相似文献
18.
Female reproductive features have been investigated in five polar and deep-sea bobtail squid genera Rossia and Neorossia ( R. macrosoma, R. moelleri, R. pacifica, N.c. caroli and N.c. jeannae). These species are characterized by asynchronous ovary maturation, very large eggs (>10% ML), fecundity of several hundred
oocytes, very high reproductive output, and continuous spawning with low batch fecundity. This adaptive complex of reproductive
traits evolved in these small animals as an optimum strategy for polar and deep-water habitats. 相似文献
19.
A cultivation-based approach was employed to compare the culturable actinobacterial diversity associated with five marine
sponge species ( Craniella australiensis, Halichondria rugosa, Reniochalina sp., Sponge sp., and Stelletta tenuis). The phylogenetic affiliation of the actinobacterial isolates was assessed by 16S rDNA-RFLP analysis. A total of 181 actinobacterial
strains were isolated using five different culture media (denoted as M1–M5). The type of medium exhibited significant effects
on the number of actinobacteria recovered, with the highest number of isolates on M3 (63 isolates) and the lowest on M1 (12
isolates). The genera isolated were also different, with the recovery of three genera on M2 and M3, and only a single genus
on M1. The number of actinobacteria isolated from the five sponge species was significantly different, with a count of 83,
36, 30, 17, and 15 isolates from S. tenuis, H. rugosa, Sponge sp., Reniochalina sp., and C. australiensis, respectively. M3 was the best isolation medium for recovery of actinobacteria from S. tenuis, H. rugosa, and Sponge sp., while no specific medium preference was observed for the recovery of actinobacteria from Reniochalina sp., and C. australiensis. The RFLP fingerprinting of 16S rDNA genes digested with HhaI revealed six different patterns, in which 16 representative 16S rDNAs were fully sequenced. Phylogenetic analysis indicated
that 12 strains belong to the group Streptomyces, three strains belong to Pseudonocardia, and one strain belongs to Nocardia. Two strains C14 (from C. australiensis) and N13 (from Sponge sp.) have only 96.26% and 96.27% similarity to earlier published sequences, and are therefore potential candidates for new
species. The highest diversity of three actinobacteria genera was obtained from Sponge sp., though the number of isolates was low. Two genera of actinobacteria, Streptomyces, and Pseudonocardia, were isolated from both S. tenuis and C. australiensis. Only the genus of Streptomyces was isolated from H. rugosa and Reniochalina sp. Sponge species have been demonstrated here to vary as sources of culturable actinobacterial diversity, and the methods
for sampling such diversity presented may be useful for improved sampling of such diversity. 相似文献
20.
Karyological observations on 7 species and 2 varieties of 4 genera belonging to the Chloranthaceae demonstrate the presence of three basic chromosome numbers within the family, i.e., x = 8 ( Hedyosmum), 13 ( Ascarina) and 15 ( Chloranthus, Sarcandra). The karyomorphology of Chloranthus and Ascarina is similar, whereas Sarcandra and Hedyosmum display unique characteristics. Both karyological aspects, i.e., chromosome number and karyomorphology, demonstrate remarkable diversity of Chloranthaceae and complex relationships between its genera. A distant affinity between Chloranthaceae and Piperales is suggested.Presented at the XV International Botanical Congress Yokohama 1993, Symposium on Relationships and Evolution of Primitive Angiosperms: Multidisciplinary Approaches. 相似文献
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