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1.
2.
The essential oils of Stachys alpina L., Stachys officinalis (L.) Trevis., Stachys palustris L., Stachys recta L. subsp. recta, S. recta L. subsp. subcrenata (Vis.) Briq., Stachys salviifolia Ten., and Stachys sylvatica L. were obtained by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). Sesquiterpene hydrocarbons were the main group of constituents of all taxa, except S. alpina, which was rich in oxygenated sesquiterpenes. S. alpina and S. palustris had a significant aldehyde fraction and a high amount of alcohols. Some differences in the essential oil composition of two subspecies of S. recta (S. recta subsp. recta and S. recta subsp. subcrenata), growing under almost identical conditions, have been found.  相似文献   

3.
Echinococcus felidis had been described in 1937 from African lions, but was later included in Echinococcus granulosus as a subspecies or a strain. In the absence of any genetic characterization, most previous records of this taxon from a variety of large African mammals remained unconfirmed due to the lack of diagnostic criteria and the possible confusion with the sympatric E. granulosus sensu stricto, Echinococcus ortleppi and Echinococcus canadensis. In this study, we obtained taeniid eggs from lion feces in Uganda and amplified DNA from individual eggs. Mitochondrial and nuclear DNA sequences showed similarities with those of other Echinococcus spp., but high values of percentage divergence of mitochondrial genes indicated the presence of a distinct species. In a second step, we compared this material with the preserved specimens of adult E. granulosus felidis, which had been identified morphologically approximately 40 years ago in South Africa. All DNA fragments (<200 bp) that could be amplified from the adults showed 100% similarity with the Ugandan material. In the phylogenetic tree of Echinococcus which was constructed from the mitochondrial genes, E. felidis is positioned as a sister taxon of E. granulosus sensu stricto. The data obtained will facilitate the development of diagnostic tools necessary to study the epidemiology of this enigmatic parasite.  相似文献   

4.
海南岛中南部山地林区产的小泡巨鼠(Rattus edwardsi)与分布于华南地区的模式亚种(R.e.edwardsi)、分布于四川的亚种(R.e.gigas)明显不同,与国外产的马来半岛亚种(R.e.ciliatus)、苏门答腊亚种(R.e.setiger)及苏门答腊西部亚种(R.e.siporanus)亦有明显的差别,经研究为一新亚种,定名为小泡巨鼠海南亚种Rattus edwardsi hainanensis Xu et Yu subsp.nov.。  相似文献   

5.
To detect the genomic constitutions and investigate the evolutionary relationships between Campeiostachys Drobov and Elymus L. species, we have cloned and analyzed 271 5S nuclear ribosomal DNA sequences from 27 accessions of these species, mostly of Chinese origin. We identified Long H1, Short S1, and Long Y1 unit classes in nine Campeiostachys or Elymus species. The identification of the three orthologous unit classes was confirmed by the neighbor‐joining tree of each unit class from PAUP and the phylogeny tree of three unit classes from MrBayes. The results suggested that these Elymus species comprise StYH haplomes and should be included in Campeiostachys. The phylogeny tree showed a clear separation between the S1 unit class and Y1 unit class. However, Y1 unit class sequences formed a sister clade to the S1 unit class, implying that although the St and Y haplomes might have some affinity, they are distinct from one another. The phylogeny tree also indicated that the five species in sect. Turczaninovia (C. dahurica var. cylindrica, C. dahurica var. dahurica, C. dahurica var. tangutorum, E. purpuraristatus, and E. dahuricus Turcz. ex Griseb. var. violeus C. P. Wang & H. L. Yang) might share a more recent common ancestor, whereas the four species in sect. Elymus (C. nutans, E. breviaristatus (Keng) Keng ex Keng f., E. sinosubmuticus (Keng) Keng f., and E. atratus (Nevski) Hand.‐Mazz.) share a close relationship. By identifying only one type of unit class for each haplome, we propose that the 5S nuclear ribosomal DNA sequences of species within Campeiostachys might have undergone haplome‐specific concerted evolution.  相似文献   

6.
Anny Rentzou  George K. Psaras   《Flora》2008,203(4):350-357
Wood and pith of 1–2-year-old stems of three woody species with different life strategies common in the Mediterranean basin were studied during the year regarding (i) the occurrence of green plastids, (ii) their maximal photosystem II photochemical efficiency (Fv/Fm) and (iii) their starch content. Green plastids were identified from the red chlorophyll auto-fluorescence under epi-fluorescence microscope, Fv/Fm was estimated using imaging-PAM fluorometry and starch content was recorded under bright field microscope after iodine staining. The evergreen sclerophyll Nerium oleander, the summer deciduous Euphorbia acanthothamnos and the winter deciduous species Platanus orientalis were selected for the study.

Epi-fluorescence microscopy revealed that (i) all species possess abundant green plastids in their wood ray and pith cells throughout the year. In the winter deciduous species chlorophyll fluorescence was found to be strong during the leafless period. By contrast, in the evergreen and the summer deciduous species chlorophyll fluorescence was found uniformly bright during the year; (ii) Fv/Fm value variation during the year seems to be species-specific: in the wood of N. oleander it remains unchanged whereas in the pith it is low during spring–summer; in both tissues of E. acanthothamnos Fv/Fm value reaches maximal value during spring and in P. orientalis during autumn; (iii) in N. oleander and E. acanthothamnos starch is accumulated during spring, whereas in P. orientalis starch content is high during winter.

The scanning electron microscopy (SEM) investigation revealed that the stem epidermis of all three species lacks stomata and formation of lenticels is delayed. Provided that gas exchange is therefore minimized and that PSII photochemical efficiency of inner stem tissues is relatively high, it is further supported that green plastids of wood ray and pith cells may help toward the re-fixation of the internally respired CO2.  相似文献   


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本文报道曲霉属及其相关的有性型属、即散囊菌属和裸胞壳属的分类群共15个,其中新变种1个,我国新记录3个。它们是:日本曲霉小囊变种(新变种),赭曲霉,蜂蜜曲霉,孔曲霉,埋藏曲霉(新记录),佩特曲霉(新记录)、亮白曲霉,阿姆斯特丹散囊菌,谢瓦散囊菌,腊叶散囊菌,赤散囊菌,匍匐散囊菌原变种,构巢裸胞壳,无冠裸胞壳和刺孢裸胞壳(新记录)。  相似文献   

9.
The genus Elaeocarpus contains approximately 360 species and occurs in mesic forest communities from India, through to China, Southeast Asia, New Guinea, Australia, and New Caledonia. Elaeocarpus fossils are best known from the Eocene to the Miocene of Australia and the late Pliocene–early Pleistocene of India, but have not been documented from East Asia before. Here we describe six new species of Elaeocarpus, E. nanningensis sp. nov. from the late Oligocene Yongning Formation of the Nanning Basin, E. presikkimensis sp. nov. from the Miocene Erzitang Formation of the Guiping Basin, E. prerugosus sp. nov., E. prelacunosus sp. nov., E. preserratus sp. nov., and E. preprunifolioides sp. nov. from the late Miocene Foluo Formation of the Nankang Basin in Guangxi, South China. This is the first reliable report for the genus occurring in East Asia, and the fossils indicate that Elaeocarpus had colonized this region by the late Oligocene and represented by a morphologically diverse group of species by the late Miocene. This sheds new insights into the timing and migration patterns of the genus in East Asia. Elaeocarpus is typically a rainforest genus occurring in mesic forests. Based on the habitat of their morphologically similar modern relatives we propose that these three sedimentary basins were warm and wet adjacent to mountainous regions with the evergreen or rain forests during the late Oligocene to Miocene.  相似文献   

10.
Twelve species of the harpacticoid genus Elaphoidella, most of them exclusively groundwater species, have been recorded in Slovenia (SE Europe). Their distribution and ecology are reviewed with the aim of evaluating distribution patterns, species preferences for groundwater habitats, ecological preferences and interactions with other copepod species at regional scale. Data on Elaphoidella species were obtained partly from the existing literature and partly from the author's (AB) own sampling campaigns carried out together with his co-workers. During the rich history of collecting copepods in Slovenia (from the 1920s to present), Elaphoidella species were recorded at 78 sampling sites altogether. The majority of collecting was conducted in the southern (Dinaric region) and north-western (Alpine region) Slovenia. The most intensively sampled habitats were porous aquifers of alluvial plains, springs in the karstic unsaturated zone and percolation water in caves. The highest species richness of Elaphoidella was recorded in the southern Slovenia, where 10 species were found. The strictly “Dinaric” species are E. charon, E. franci, E. karstica, E. stammeri, E. sp. 1 and E. sp. 2, while E. phreatica and E. bidens were found exclusively in the north-western Slovenia. From the latest data on the copepod distributions (2002–2004), where the environmental characteristics of sampling sites were also measured, the relationship between selected environmental characteristics of the habitats and the presence of Elaphoidella species was analysed. The distribution of Elaphoidella species in Slovenia was found to be related with the region, habitat type, altitude, conductivity and pH of the water.  相似文献   

11.
菰属系统与演化研究——外部形态   总被引:3,自引:3,他引:0  
陈守良 《植物研究》1991,11(2):59-73
本文研究菰属Zizania L.及其有关属、种的外部形态后,揭示出菰属应在禾本科Gramineaee稻族Oryzeae中独立成菰亚族Zizaniinae。其与水稻属Oryza L.或拟菰属Zizaniopsis Doel&Aschers。在远古时代都可能起源于一个现已灭迹的共同祖先,而后平行向前演化。  相似文献   

12.
A gene encoding a protein kinase was identified by homology-based PCR amplification in Encephalitozoon intestinalis, a microsporidian parasite pathogenic to humans, and its orthologue has been identified by database mining in the genome of the related species E. cuniculi, whose sequence has been recently published. Phylogenetic analysis revealed that the proteins encoded by these genes are homologues of the cAMP-dependent protein kinase catalytic subunits (PKAc). Southern blot analysis indicated that the EiPKAc gene is present in two copies in the E. intestinalis genome, whereas the E. cuniculi orthologue (EcPKAc) is a single copy gene. RT-PCR data showed that the EiPKAc gene is expressed in at least one of the intracellular stages during infection of the mammalian host cell by E. intestinalis.  相似文献   

13.
粗糠树是紫草科厚壳村亚科厚壳树属植物,广布于我国长江以南及台湾,在西藏、青海、甘肃及陕西也有少量分布。学名通常采用E.dicksoniHance (1862),标式标本采自湖北。  相似文献   

14.
Baldellia ranunculoides (L.) Parl. (Alismataceae) is a taxonomically problematic aquatic plant with an historically ill-defined distribution and global conservation status. This paper finds morphological, ecological and molecular evidence for two distinct taxa, probably best described as subspecies: (1) B. ranunculoides subsp. ranunculoides and (2) B. ranunculoides subsp. repens and provides detailed distribution data on their overlapping range, in different habitats, across the cool, high rainfall areas of western Europe and west Mediterranean. The two subspecies are amongst the relatively large number of threatened European and north Africa aquatic plants and this paper provides a systematic review of their relative conservation pressures and management needs, with particular emphasis on the status of both taxa in central Europe. Other observations indicate probable evolutionary relationships within B. ranunculoides s.l. and its associated taxa and the review points out where these and other research topics could potentially be pursued.  相似文献   

15.
Emericella venezuelensis is a new species, differing from two other species with stellate ascospores, E. variecolor and E. pluriseminata, by triangular flaps on the convex sides of the ascospores, and further from E. variecolor by producing an Aspergillus anamorph only on unconventional growth media. The three species also differ in their profiles of extrolites (secondary metabolites). Emericella venezuelensis produces aflatoxin B1, sterigmatocystin, and terrein and compounds with chromophores of the shamixanthone, emerin and desertorin type of compounds. E. variecolor produces asteltoxin, shamixanthone, asperthecin, and terrein, in addition to metabolites unequivocally recorded in the literature or tentatively identified here as astellolide A & B, andibenin A, B, C, andilesin A, B, C, anditomin, astellatol, stellatic acid, stellatin, tajixanthone, radixanthone, najamxanthone, ajamxanthone, variecoxanthone A, B, C, isoemericellin, kojic acid, varitriol, varioxiran, dihydroterrein, 7-hydroxyemodin, avariquinone and stromemycin. E. pluriseminata produces several unknown specific extrolites. E. venezuelensis is the first organism of marine origin reported to produce aflatoxin. Aflatoxin production by E. venezuelensis makes this species an attractive model organism for the study of the regulation of this important type of carcinogenic mycotoxins in combination with the knowledge on sterigmatocystin production by E. nidulans, soon to be whole genome sequenced. The isolates were also analyzed cladistically using partial sequences of the β-tubulin gene. Since three species of Emericella have stellate ascospores, and the type material of E. variecolor is equivocal, this species is epitypified with CBS 598.65. Emericella species normally do not appear to cause problems for food safety, as they are most often found in litter and soil.  相似文献   

16.
Analysis of the isothiocyanates arising from enzymatic hydrolysis of glucosinolate extracts of Tropaeolum tuberosum supports the assessment of two subspecies. Seeds, tubers, leaves and flowers of T tuberosum subsp. tuberosum produced p-methoxybenzyl isothiocyanate. Subspecies silvestre produced benzyl-, 2-propyl- and 2-butylisothiocyanates. N,N-Di(4-methoxybenzyl)thiourea was detected in tuber extracts of subsp. tuberosum by HPLC.  相似文献   

17.
Ehrendorferiana and its two included new species, E. austrocedri (the type species) and E. fitzroyae, are diagnosed. The new genus is a member of the predominantly temperate Neotropical subfamily Aphalaroidinae (Psyllidae). Based on the absence of metabasitarsal spurs it forms a likely monophyletic group with Baccharopelma, Panisopelma and Russelliana. The absence or paucity of long dorsal or marginal setae on the wing pads and caudal plate suggests a probable sister-taxon relationship with Russelliana. Apart from two species of Triozidae from New Zealand on Podocarpaceae, Ehrendorferiana is unique within Psylloidea in its host association with conifers, viz. Austrocedrus and Fitzroya (both Cupressaceae).

See also Electronic Supplement at: http://www.senckenberg.de/odes/05-12.htm  相似文献   


18.
在云南景东亚热带山地常绿阔叶林中捕获了一组猪尾鼠,经鉴定为一新亚种,特予报道。  相似文献   

19.
Specific and cross-reactive antigens were defined in four species of Entamoeba: invadens, moshkovskii, Laredo and histolytica strains HM1, HM3, HM38 and HK9. Among these species extensive common reactivities were observed by immunoblot. Eight E. histolytica antigenic markers were revealed after blocking common specificities with antigens of other Entamoeba species. A monoclonal antibody (mAb) defined two protein markers of E. histolytica, M, 29 and 25 kDa. The four strains of E. histolytica, which varied in virulence as determined by the development of liver abscesses in hamsters, showed the same antigenic patterns with the mAb and with polyclonal antibodies.  相似文献   

20.
利用重复序列探针染色体荧光原位杂交(FISH)和基因组原位杂交(GISH)技术,对采自青海高原披碱草属种间天然杂种进行细胞学鉴定,同时结合物种分布及形态学特征,共揭示6种不同天然杂种的类型。第一类为垂穗披碱草(Elymus nutans Griseb.)和鹅观草属(Roegneria C.Koch)物种间的天然杂种,染色体数为35,染色体组成为StStYYH;第二类为垂穗披碱草和达乌力披碱草种(Elymus dahuricus Turcz.ex Griseb.)间杂种,染色体数为42,染色体组成为StStHHYY;第三类为达乌力披碱草和老芒麦(Elymus sibiricus L.)种间杂种,染色体数为35,染色体组成为StStHHY;第四类为垂穗披碱草和糙毛以礼草(Kengilia hirsuta Keng)种间杂种,染色体数为42,染色体组成为StStYYHP;第五类为垂穗披碱草和大颖草(Kengilia grandiglumis Keng)种间杂种,染色体数为42,染色体组成为StStYYHP;第六类为糙毛以礼草和赖草(Leymus secalinus(Georgi) Tzvel.)种间杂种,染色体数为35,染色体组成为StYPNsXm。研究结果为进一步研究披碱草属种间杂交渐渗提供了重要参考资料;同时鉴定出的天然杂种可以作为潜在的种质资源在牧草或生态草育种中加以利用。  相似文献   

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