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1.
The floral vasculature in three allied genera,Plagiorhegma, Jeffersoria andAchyls is investigated, and the results are compared with those ofEpimedium andVancouveria which are related closely toPlagiorhegma andJeffersonia. The vasculature in the receptacle ofPlagiorhegma andJeffersonia is similar, but that ofAchlys is much simpler. Slightly different trace patterns are observed in the sepals ofPlagiorhegma andJeffersonia. InJeffersonia, the 3-trace condition leaving 2 or 3 gaps is most frequently observed, but inPlagiorhegma traces of a double nature leaving a single gap are more frequent. The traces to the innermost sepals, petals and stamens are usually of a double nature leaving a single gap in both genera. Regular division and fusion are not observed in the receptacular stele. The vascular differentiation between sepals and petals is more advanced inPlagiorhegma andJeffersonia than inEpimedium andVancouveria. InAchlys, the traces are all staminal and single throughout their course. Two parts recognized in the pistils ofPlagiorhegma, Jeffersonia andAchlys are traversed by independent vasculature. The comparisons of pistil morphology including vasculature ofPlagiorhegma, Jeffersonia, Achlys, Epimedium andVancouveria lead to the interpretation that the pistils are based on the same morphological plan. The probable evolutionary trend in pistil is then suggested in these five genera.  相似文献   

2.
The postcanine dentition ofCallithrix geoffroyi, Callithrix penicillata, andCallithrix kuhli was compared metrically to determine whetherC. kuhli is a hybrid population ofC. geoffroyi andC. penicillata or not. Many measurements showed significant differences (p<0.01 orp<0.05) among the three marmosets. The dental variability inC. kuhli was not greater than those inC. geoffroyi andC. penicillata. Based on canonical analysis, the three marmosets are discriminated, andC. kuhli did not occupy a middle position betweenC. geoffroyi andC. penicillata on the first two canonical axes. In the projection of the first two principal components,C. penicillata tended to be distinguished fromC. geoffroyi andC. kuhli, andC. kuhli does not exhibit intermediacy betweenC. geoffroyi andC. penicillata. The present statistical analysis failed to provide evidence thatC. kuhli constitutes a population hybridized fromC. geoffroyi andC. penicillata, although the three marmosets were discriminated from each other. This may provide support for the hypothesis thatC. kuhli is not a hybrid population ofC. geoffroyi andC. penicillata but a distinct species.  相似文献   

3.
A study was made of the genetic variability of 101 barley populations belonging to the four, wild, Spanish species of the genusHordeum (the autogamousH. marinum subspp.marinum andgussoneanum, andH. murinum subspp.murinum andleporinum, plus the allogamous speciesH. bulbosum andH. secalinum). Electrophoresis of endosperm proteins was performed using a large number of individuals from each population sampled, in order to determine intra- and interpopulational variation. The distribution of variability observed by population and taxonomic unit, is closely related to the breeding system.Hordeum bulbosum showed the greatest intrapopulational variability andH. marinum subsp.gussoneanum the least. In contrast to the autogamous species, the allogamous species showed low levels of interpopulational variation.  相似文献   

4.
Zymograms of glucosephosphate isomerase (GPI) and phosphogluconate dehydrogenase (PGD) revealed three isozymes for each enzyme in the plant speciesScabiosa columbaria. Intergenic heterodimers are formed between the polypeptides coded byGpi-1 andGpi-2 and between those coded byPgd-1 andPgd-2, indicating that a GPI and a PGD locus have been duplicated in the past. The ancestral genes assort independently with their duplicated gene, suggesting that the duplications have originated from a process of translocation. Linkage was found only betweenGpi-1 andPgd-2 and betweenGpi-2 andPgd-1, suggesting that the duplicated loci were located on the same translocated chromosomal segment. Both duplications are present in all other examined species ofScabiosa and inCephalaria andKnautia, two other genera of the Dipsacaceae. The generaSuccisa andDipsacus, also belonging to the Dipsacaceae, do not showGpi-1 activity, makingGpi-2 andPgd-1 the most likely ancestral genes. InSuccisa, the isozymes ofGpi-1 andGpi-2 either overlap orGpi-1 has been silenced. The combined results suggest that a chromosomal segment containingGpi-2 andPgd-1 has been translocated before the divergence ofScabiosa, Cephalaria, Knautia, andSuccisa.  相似文献   

5.
A cladistic analysis of 44 species of the generaCladina andCladonia is presented.Pycnothelia papillaria, Cladia aggregata andC. retipora were used as outgroup taxa. The consensus of all equally parsimonious trees suggests a common ancestral origin for species inCladonia andCladina while the generaPycnothelia andCladia cluster outside this group. The results do not support distinction ofCladina at genus level although it is distinguished as a monophyletic group but within the genusCladonia. The current sectional division ofCladonia is not supported. SectionsCocciferae andHelopodium are best supported but even these groups as currently delimited seem to in include elements that are more closely related to species of the other sections, e.g.C. carneola of sect.Cocciferae andC. pityrophylla of sect.Helopodium. Sections such asUnciales andPerviae seem to be artificial assemblages. In general the evolutionary scheme of the genus seems to be more complicated than revealed by the current sectional division.  相似文献   

6.
The genusLepidapedon is subdivided into several species groups and subgroups of species based on the vitelline distribution and the length of the excretory vesicle. The species in each of the subgroups are listed and keys to the species in most subgroups are given. The following north-eastern Atlantic species are described or redescribed:Lepidapedon rachion fromMelanogrammus aeglefinus, Gadus morhua, Aspitrigla cuculus, Merlangius merlangus andPollachius pollachius; L. cambrensis fromEnchelyopus cimbrius; L. sommervillae n. sp. fromTrachyrincus scabrus, T. murrayi andCoryphaenoides guentheri; L. elongatum fromGadus morhua; L. gaevskayae fromCoryphaenoides (Nematonurus) armatus; L. discoveryi n. sp. fromCoryphaenoides (Nematonurus) armatus; L. arlenae n. sp. fromTrachyrincus scabrus andT. murrayi; L. mariannae n. sp. fromGaidropsarus argentatus; Lepidapedon spp. innom (Elongatum-group) fromCoryphaenoides guentheri andCoryphaenoides (Chalinura) leptolepis; L. desclersae n. sp. fromLepidion eques; L. beveridgei fromCoryphaenoides (Nematonurus) armatus andC. (Chalinura) mediterraneus; andL. zubchenkoi fromCoryphaenoides (Chalinura) leptolepis andC. (C.) profundicolus. The phylogeny, host-specificity and zoogeography of the genus are briefly discussed.  相似文献   

7.
Wu B  Isobe K  Ishii R 《Mycorrhiza》2004,14(6):391-395
Arbuscular mycorrhizal (AM) colonization was observed on four plant species in primary successional volcanic deserts on the Southeast slope of Mount Fuji. The AM colonization of the dominant species, Polygonum cuspidatum, contradicts the conclusion that Polygonaceae are often regarded as being non-mycorrhizal species. The secondary dominant species, Polygonum weyrichii var. alpinum, formed no mycorrhizas. The roots of Cirsium purpuratum, Clematis stans and Campanula punctata ssp. hondoensis, showed a higher percentage of AM colonization than P. cuspidatum. AM colonization and spore density in the rhizosphere soil of P. cuspidatum significantly decreased as elevation increased. AM colonization in roots of Cirsium purpuratum and Clematis stans also tended to decrease with increased altitudes. Cirsium purpuratum and Campanula punctata ssp. hondoensis formed single structural types of Arum- and Paris-type, respectively, whereas P. cuspidatum and Clematis stans formed both Arum- and Paris-type morphologies.  相似文献   

8.
Extent of divergence in partial nucleotide sequences from large and small subunit ribosomal RNAs was used to estimate genetic relationships among ascomycetous yeasts and yeastlike fungi. The comparisons showed four phylogenetically distinct groups comprised of the following taxa: Group 1. The budding yeastsSaccharomyces, Saccharomycopsis, Debaryomyces, Metschnikowia, Saturnospora, andLipomyces, and the yeastlike generaAscoidea, Cephaloascus, Dipodascus, Dipodascopsis, andGalactomyces; Group 2.Eremascus, Emericella andCeratocystis; Group 3.Taphrina andProtomyces; Group 4.Schizosaccharomyces. Because of the genetic relationships indicated by sequence analysis, Group 1 taxa are retained in the order Endomycetales, andSchizosaccharomyces is retained in the Schizosaccharomycetales Prillinger et al. ex Kurtzman.  相似文献   

9.
To understand the relationship between the expression and the genomic organization of the zebrafishdlxgenes, we have determined the genomic structure of thedlx2anddlx4loci. This led to the identification of the zebrafishdlx1anddlx6genes, which are closely linked todlx2anddlx4,respectively. Therefore, the inverted convergent configuration ofDlxgenes is conserved among vertebrates. Analysis of the expression patterns ofdlx1anddlx6showed striking similarities to those ofdlx2anddlx4,respectively, the genes to which they are linked. Furthermore, the expression patterns ofdlx3anddlx7,which likely constitute a third pair of convergently transcribed genes, are indistinguishable. Thus, the overlapping expression patterns of linkedDlxgenes during embryonic development suggest that they sharecis-acting sequences that control their spatiotemporal expression. The evolutionary conservation of the genomic organization and combinatorial expression ofDlxgenes in distantly related vertebrates suggest tight control mechanisms that are essential for their function during development.  相似文献   

10.
Plant species distribution was studied on five reclaimed lands and one intertidal flat (control) on the western coast of Korea. Nineteen soil properties were analyzed. Of these, soil moisture, electrical conductivity, and levels of Na and Cl had the greatest effect on plant distribution. The plant species were divided into four groups, according to the amount of soil moisture found at their habitats.Triglochin maritimum andTypha angustata were found on the wettest sites;Phragmites communis, Carex scabrifolia, Suaeda japonica, Zoysia sinica, andSalicornia herbacea in places with relatively high moisture;Aster tripolium andPhacelurus latifolius in areas with medium levels of moisture; andAtriplex subcordata, Chenopodium virgatum, andTrifolium repens in the driest areas. The species also were divided into four groups, according to the degree of soil electrical conductivity: Highest,S. herbacea, Limonium tetragonum, Suaeda asparagoides, andS. japonica; Relatively high,A. tripolium, C. scabrifolia, P. communis, Artemisia scoparia, andZ sinka; Relatively low,Setaria viridis, C. virgatum, Sonchus brachyotus, A. subcordata, Calamagrostis epigeios, andT. angustata; and Lowest,Imperata cylindrica var.koenigii, Aeschynomene indica, Lotus corniculatus var.japonicus, andT. repens. On reclaimed land, plant species were found in zones, according to the degree of desalinization (i.e., levels of Na and Cl).  相似文献   

11.
Sequences of the internal transcribed spacer region 1 (ITS1) of the ribosomal DNA were used to determine the phylogenetic relationships of species ofTrichodermasect.Pachybasium.To this end, 85 strains—including all the availableex-type strains—were analyzed. Parsimony analysis demonstrated that the section is nonmonophyletic, distributing the 85 strains among three main groups that were supported by bootstrap values. Group A comprises two clades (A1 and A2), with A1 includingT. polysporum, T. piluliferum,andT. minutisporum,while A2 includedT. hamatum, T. pubescens,andT. strigosumin addition to species previously included in sect.Trichoderma(i.e.,T. viride, T. atroviride,andT. koningii). Theex-type strain ofT. fasciculatumformed a separate branch basal to clade A. Clade B contained the sect.PachybasiummembersT. harzianum, T. fertile, T. croceum, T. longipile, T. strictipile, T. tomentosum, T. oblongisporum, T. flavofuscum, T. spirale,and the anamorphs ofHypocrea semiorbisandH. cf. gelatinosa.Sequence differences among clades A1, A2, and B were in the same order of magnitude as between each of them andT. longibrachiatum,which was used as an outgroup in these analyses. Sequence differences within clades A1, A2, and B were considerably smaller: in some cases (i.e.,T. virensandT. flavofuscum; T. strictipileandH. cf. gelatinosa), the ITS1-sequences were identical, suggesting conspecifity. In other cases (e.g.,T. crassumandT. longipile; T. harzianum, T. inhamatum, T. croceum, T. fertile,andH. semiorbis; T. hamatumandT. pubescens;andT. viride, T. atroviride,andT. koningii) differences were in the range of 1–3 nt only, suggesting a very close phylogenetic relationship. The sequence of a previously described aggressive mushroom competitor group ofT. harzianumstrains (Th2) was strikingly different from that of theex-type strain ofT. harzianumand closely related species and is likely to be a separate species.  相似文献   

12.
Plant community structure in reclaimed lands on the West Coast of Korea   总被引:1,自引:0,他引:1  
Plant species distribution was studied on five reclaimed lands and one intertidal flat (control) on the western coast of Korea. Nineteen soil properties were analyzed. Of these, soil moisture, electrical conductivity, and levels of Na and Cl had the greatest effect on plant distribution. The plant species were divided into four groups, according to the amount of soil moisture found at their habitats.Triglochin maritimum andTypha angustata were found on the wettest sites;Phragmites communis, Carex scabrifolia, Suaeda japonica, Zoysia sinica, andSalicornia herbacea in places with relatively high moisture;Aster tripolium andPhacelurus latifolius in areas with medium levels of moisture; andAtriplex subcordata, Chenopodium virgatum, andTrifolium repens in the driest areas. The species also were divided into four groups, according to the degree of soil electrical conductivity: Highest,S. herbacea, Limonium tetragonum, Suaeda asparagoides, andS. japonica; Relatively high,A. tripolium, C. scabrifolia, P. communis, Artemisia scoparia, andZ sinka; Relatively low,Setaria viridis, C. virgatum, Sonchus brachyotus, A. subcordata, Calamagrostis epigeios, andT. angustata; and Lowest,Imperata cylindrica var.koenigii, Aeschynomene indica, Lotus corniculatus var.japonicus, andT. repens. On reclaimed land, plant species were found in zones, according to the degree of desalinization (i.e., levels of Na and Cl).  相似文献   

13.
Summary Pollen and spore concentrations were compared in Tartu, Estonia and in three sites in Finland (Turku, Kuopio and Oulu) during May–September 1989. The onset ofQuercus, Pinus, Poaceae,Urtica andRumex flowering started earlier in Tartu than at any site in Finland. The flowering ofJuniperus andArtemisia, on the other hand, began earlier in Turku and Kuopio than in Tartu.Pinus andJuniperus showed a significant correlation (number of pollen grains at the same date) between Tartu and Turku and between Turku and Kuopio. Poaceae andUrtica were correlated between all the sites, as wasRumex except between Tartu and Turku.Artemisia was correlated between Tartu and Turku, Turku and Oulu, and Kuopio and Oulu.Cladosporium correlated between Tartu and Turku. The pollen seasons of Poaceae,Urtica andRumex are prolonged towards the south.  相似文献   

14.
Although several investigations have been made from different viewpoints, the classification or interspecific relationships ofSaguinus still remain uncertain. In the present study, we applied multivariate analysis methods to dental measurements of part ofSaguinus populations of sufficient sample size and obtained the following conclusions.Saguinus can be classified into two main groups: one consists ofS. oedipus andS. leucopus, and the other ofS. fuscicollis, S. nigricollis, S. labiatus, andS. mystax. Concerning the former group, the two subspecies ofS. oedipus, S. o. oedipus, andS. o. geoffroyi, show a close affinity with each other and also a close relationship toS. leucopus, while the latter group consists of two subgroups of species, one includingS. fuscicollis andS. nigricollis, and the other includingS. labiatus andS. mystax. The biological distance betweenS. oedipus oedipus andS. o. geoffroyi is slightly larger than that between the pairs ofS. fuscicollis andS. nigricollis and ofS. labiatus andS. mystax. Factor analysis revealed significant factors which could explain the differences among the seven maleSaguinus populations. Taking all the results into account, it seems necessary to reconsider the phylogenetic relationships within the genusSaguinus.  相似文献   

15.
Cytotaxonomical investigations on 11 species from the Western Himalayas show that 8 are diploid and the remaining tetraploid. The numbers for three species are new.P. prescottianum (2x) andP. thomsoni (4x), andP. stimulans (2x) andP. acanthophyllum (4x) are closely related but distinct species pairs.  相似文献   

16.
The phylogeny of the subfamilyRubioideae (Rubiaceae) was estimated from sequence variation in therps16 intron (cpDNA) in 143 ingroup and 5 outgroup taxa. The analysis largely confirms a recent one based onrbcL sequences, but branch support is often much stronger. Three of the traditional subfamilies are supported,Rubioideae, Cinchonoideae s. str., andIxoroideae s. l. while there is no support forAntirheoideae. TheRubioideae are the sister group of all otherRubiaceae and comprise the tribesAnthospermeae, Coccocypseleae, Cruckshanksieae, Coussareeae, Gaertnereae, Hedyotideae, Knoxieae, Morindeae, Ophiorrhizeae, Paederieae, Pauridiantheae, Perameae, Psychotrieae, Rubieae, Spermacoceae, Theligoneae, andUrophylleae. TheHamelieae andHillieae belong to theCinchonoideae. Rachicallis andSiemensia should be transferred from theHedyotideae to theCinchonoideae. ThePauridiantheae, Urophylleae, Ophiorrhizeae, andRaritebe form the basalmost subclade of theRubioideae. The second basalmost clade consists of the generaLasianthus andPerama. The third basalmost clade consists of the tribesCoussareeae, Coccocypseleae andCruckshanksieae, and the generaDeclieuxia andHindsia. The tribesKnoxieae, Anthospermeae, Argostemmateae, Paederieae, Theligoneae, Rubieae, Hedyotideae, andSpermacoceae are members of one clade. TheKnoxieae are monophyletic ifOtiophora, Otomeria, andPentas are included. The tribeAnthospermeae is supported as monophyletic, but its subtribes are not. ThePaederieae, together withTheligonum, form a paraphyletic grade basal to theRubieae. TheHedyotideae, includingSchismatoclada, form a grade at the base of theSpermacoceae. TheGaertnereae are monophyletic and distinct from thePsychotrieae. TheMorindeae are monophyletic and includeDamnacanthus andMitchella. Schradera is the sister group of theMorindeae. ThePsychotrieae are monophyletic when theGaertnereae, Lasianthus, andDeclieuxia are excluded. The recognition of a subtribeHydnophytineae leaves the rest of thePsychotrieae paraphyletic.Psychotria is paraphyletic with respect to all other genera of the tribe. Approximately 50 genera are here classified for the first time based on molecular data.  相似文献   

17.
The sieve-element plastids of members of several genera in theBuxaceae (Buxus, Pachysandra andSarcococca) were found to be of the specific subtype PVI, which contains a central globular protein crystal.Simmondsia (Simmondsiaceae) andDaphniphyllum (Daphniphyllaceae), on the other hand, were found to contain S-type sieve-element plastids. The occurrence of the highly restricted PVI plastids in theBuxaceae mitigates against a close relationship between theBuxaceae andSimmondsia, Daphniphyllum andEuphorbiaceae. Exine sculpturing of theBuxaceae andSimmondsiaceae also shows no close similarities. Both of these EM characters are discussed in connection with other available data and with respect to earlier systematic treatment of these families.  相似文献   

18.
Andrew Henderson 《Brittonia》1999,51(1):106-113
The Euterpeinae contains six neotropical genera. There has been continual disagreement on generic and subgeneric boundaries in the subtribe.Euterpe andPrestoea, andJessenia andOenocarpus, have been repeatedly united and separated. A phylogenetic analysis based on 54 morphological and anatomical characters gave one tree of 127 steps.Euterpe is separate fromPrestoea, butJessenia andOenocarpus are best treated as one genus. Subgeneric relationships ofEuterpe andOenocarpus are also analyzed and discussed.  相似文献   

19.
Antigenic mannans isolated from the cells ofSaccharomyces fermentati, Saccharomyces rosei,Saccharomyces delbrueckii, Torulopsis colliculosa, Candida albicans andSaccharomyces cerevisiae were examined for their reactivity withSaccharomyces fermentati andCandida albicans antisera. Mannans ofTorulaspora as well asCandida albicans showed high cross-reactivity with the investigated antisera, which could be due to the presence of long side chains established by the partial acetolysis method. The low specific rotations ofSaccharomyces fermentati, Saccharomyces rosei andTorulopsis colliculosa mannans indicate a predominance of β-glycosidio linkages, whereasSaccharomyces delbrueckii andCandida albicans mannans possess predominantly α-linkages.Saccharomyces cerevisiae mannan showed different structural and immunological properties.  相似文献   

20.
Suh  Sung-Oui  Sugiyama  Junta 《Mycoscience》1994,35(4):367-375
The 18S ribosomal RNA gene sequences of the basidiomycetous yeastsKondoa malvinella andRhodosporidium dacryoidum, and an anamorphic yeastSympodiomycopsis paphiopedili were determined. The 18S rRNA gene ofR. dacryodium IAM 13522 (ex type) revealed the presence of an intron-like region with a length of 404 nucleotides, which is presumably assigned to a group I intron. The phylogenetic tree, including 34 published reference sequences, was inferred from 1493 sites which could be unambiguously aligned. The molecular phylogeny, using the ascomycetes as an outgroup, divided the basidiomycetes into three major lineages. The first lineage was composed of the smut fungi (Ustilaginales), represented byUstilago maydis, U. hordei, andTilletia caries, includingS. paphiopedili. The second lineage included the type species of teliospore-forming yeast generaLeucosporidium, Rhodosporidium, andSporidiobolus, and the generaErythrobasidium andKondoa, both previously included in the Filobasidiaceae.Rhodosporidium dacryodium showed a close relationship withE. hasegawianum, which was backed by a high bootstrap support. The rust fungiCronartium ribicola andPeridermium harknessii were also included in this lineage. The last lineage was formed by the filobasidiaceous yeasts,Cystofilobasidium capitatum, Mrakia frigida, Filobasidium floriforme, andFilobasidiella neoformans, and the anamorphic yeastsBullera alba (the anamorph ofBulleromyces albus) andTrichosporon cutaneum. Members ofTremella and selected hymenomycetous genera were also included in this lineage.The nucleotide sequence data reported in this paper will appear in the GSDB, DDBJ, EMBL and NCBI nucleotide sequence databases with the following accession numbers D13459 (Rhodosporidium dacryodium), D13776 (Kondoa malvinella), and D14006 (Sympodiomycopsis paphiopedili).  相似文献   

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