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1.
The closely related species, diploidAnthoxanthum alpinum Á. Löve etD. Löve and tetraploidAnthoxanthum odoratum L., have distinct distributions:A. alpinum is an arctic-alpine species, whileA. odoratum is a species of lower altitudes and more southerly latitudes. However, some authors suggest that both species are potentially able to maintain their populations in the distribution area of the other species. Reciprocal transplant experiments in two mountain localities (one withA. alpinum, the other withA. odoratum) were carried out to study the survival and vegetative and generative reproduction of tussocks of both species in the area of distribution of the other species. The mortality of tussocks ofA. alpinum was higher in the “alien” locality, the life span of tillers was greatly reduced and the size of tussocks decreased considerably during the experiment compared to its “native” locality. These results suggest that there was a lack of favourable microsites forA. alpinum in the “alien” locality probably caused by the presence of strong competitors.A. odoratum flowered far less in the “alien” locality (both on tussocks and tillers) compared to the “native” one. These results suggest that environmental conditions are not suitable for the flowering ofA. odoratum in the “alien” locality. We conclude thatA. alpinum could have been limited in extending its distribution into the area ofA. odoratum by the presence of strong competitors, whileA. odoratum could have been limited by its ability to reproduce by seed.  相似文献   

2.
The phylogenetic relationship of the Korean endemic genus,Hanabusaya, to other campanulaceous genera has been controversial since it was described by Nakai in 1911. Three genera of Campanuloideae,Symphyandra, Adenophora, andCampanula, have been considered closely related by various taxonomists on the basis of anther shape, gross morphology, and pollen characters, respectively. We have tested these competing taxonomic hypotheses using the internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA from 12 taxa representing 7 genera of Campanulaceae. The molecular phylogeny indicates strongly thatHanabusaya is more closely allied toAdenophora than toCampanula orSymphyandra. The phylogenetic affinity ofHanabusaya andAdenophora is supported by a 100% bootstrap value and a high decay index (13). The average sequence divergence value (Kimura’s 2-parameter method) betweenHanabusaya and theAdenophora species is 2.58. The value is significantly (about ten times) lower than the ones observed betweenHanabusaya and the species ofCampanula (average of 23.52) and betweenHanabusaya andSymphyandra (24.95). The ITS sequence phylogeny suggests that some morphological characters, such as fused anthers and corolla shape, are homoplastic in the Campanulaceae genera.  相似文献   

3.
Sau3AI shot gun cloning and colony hybridization with total genomic probes were used to isolate genome-specific sequences inPhleum species. The total DNA isolated from diploid speciesP. alpinum andP. bertolonii was partially digested withSau3AI and cloned using pUC19 as a vector to anE. coli strain DH5mcr. A partial genomic DNA library consisting of 3030 colonies for the genome ofP. alpinum and one consisting of 3240 colonies for the genome ofP. bertolonii were constructed. Twelve hundred and thirty colonies from the DNA library ofP. alpinum and 1320 from that ofP. bertolonii were respectively blotted to membrane filters and hybridized to the total genomic probes from these two species. Eight clones specific toP. alpinum and 13 specific toP. bertolonii were isolated through colony hybridization and further dot-blot hybridization. Most of these clones may carry highly or moderately repetitive sequences. Three sequences specific toP. alpinum and 3 specific toP. bertolonii were used as probes to hybridize theEcoRI-digested DNA samples from four species,P. alpinum,P. bertolonii,P. pratense andP. montanum, on Southern blot. The results from these hybridization experiments showed that all 3P. bertolonii-specific probes and 2 of the 3P. alpinum-specific probes hybridized to the DNA ofP. pratense, thus confirming the conclusion of the close relationships between the cultivated timothy and its two wild relatives that was drawn in our previous study using the C-banding technique.  相似文献   

4.
Summary An autotetraploidA. alpinum was found in France. In theA. odoratum group only tetraploids were known up to now, but widespreaded diploids have been discovered in Southern Europe. Investigations of karyotypes led to the recognition of six diploid genomes in perennial Anthoxanthums; four were found in diploids, two only in allotetraploids.  相似文献   

5.
Larvae of Axarus andLipiniella share several apparantly apomorphic features of the mouth-part structure, however adults ofLipiniella show possible relationships toDemeijerea andChironomus. In order to assist in refining the relationships ofAxarus toLipiniella the karyotype ofAxarus festivus was determined and compared to the karyotypes ofLipiniella arenicola andL. moderata. Larvae ofA. festivus from a population in Kansas were monomorphous, with 2n=8, the Ist, IInd and IIIrd chromosomes metacentric, and IVth acrocentric.Axarus festivus therefore differs fromL. arenicola in chromosome number (2n=6), however homologous sections of all chromosomes were identified. Inversions were detected in the Ist, IInd and IIIrd chromosomes ofA. festivus relative toL. arenicola. It was determined that both species have high functional activity, as indicated by the presence of three Balbiani rings, and more than one nucleolus per genome. Differing degrees of polyteny, a feature previously described forL. arenicola, were observed in the salivary glands, with highest degrees of polyteny in cells near the salivary duct. These similarities of chromosome structure indicate close genetic relationships betweenA. festivus andL. arenicola. However, we did not find evidence for similarity ofA. festivus toL. moderata, which supports the previous conclusions byKiknadze et al. (1989) regardingL. arenicola andL. moderata.  相似文献   

6.
Pinus hakkodensis has been considered as a hybrid betweenP. pumila andP. parviflora var.pentaphylla. Chloroplast DNA typing of this putative hybrid and hypothesized parental species in the Tanigawa Mountains, Japan, was conducted by PCR and single-strand conformation polymorphism (SSCP) of the intergenic spacer betweentrnL(UAA)3′ exon andtrnF(GAA) of cpDNA. Each of the hypothesized parental species collected from other mountain regions displayed a diagnostic SSCP pattern, whereas all morphological intermediates sampled in the Tanigawa Mountains had the SSCP pattern ofP. parviflora var.pentaphylla. Furthermore, some individuals classified on the basis of needle morphology as belonging toP. pumila in this mountain region showed the SSCP pattern ofP. parviflora var.pentaphylla. This may suggest that pollen-mediated uni-directional introgression fromP. parviflora var.pentaphylla toP. pumila occurs in the Tanigawa Mountains.  相似文献   

7.
The sex-specific growth factors produced by thea and mating types ofKluyveromyces lactis were examined for interspecies cross-reactivity on growing cells ofKluyveromyces aestuarii andKluyveromyces delphensis. Taxonomically,K. aestuarii is closely related toK. lactis;K. delphensis is more distantly related. Reciprocal growth responses occurred betweenK. aestuarii and the a mating type ofK. lactis; no response was evident betweenK. delphensis and either sex ofK. lactis.  相似文献   

8.
Morphological variation was analyzed in the endangeredBetula uber and sympatric dark-barked tree birches,B. lenta andB. alleghaniensis, to determine the extent of differences among the three taxa. Univariate and multivariate analyses of leaf and fruit characters indicated that the three taxa are morphologically distinct, thatB. uber is more similar toB. lenta than toB. alleghaniensis, that intermediates betweenB. uber andB. lenta do not occur, and that leaves are necessary for absolute separation ofB. uber fromB. lenta because of overlap of fruit characters. Field observations of the bark indicate no differences betweenB. uber andB. lenta while those of growth form suggest thatB. uber may have a more compact crown thanB. lenta. The evidence presented here supports an alliance ofB. uber with the dark-barked tree birches (seriesCostatae).  相似文献   

9.
Theligonum cynocrambe and 13 species ofRubiaceae contain S-type sieve-element plastids, wide-spread in Dicotyledons. Alignment ofTheligonum toCaryophyllales (Centrospermae), especiallyPhytolaccaceae, is unlikely, because this order is characterized by specific P-type plastids. SEM investigations show the pollen exine ofTheligonum to be microreticulate, with additional supratectate spinules.Asperula and other genera of the tribeRubieae have a tectum perforatum (punctitegillate sexine), also with supratectate verrucae or spinulae.—Thus ultrastructure suggests (but not definitely proves) relationships betweenTheligonum andRubiaceae, while affinities betweenTheligonum andCaryophyllales are excluded.
  相似文献   

10.
Numerical taxonomy of some species of hypoxylon   总被引:1,自引:0,他引:1  
Numerical analysis has resulted in a division of the coloured and non-coloured species ofHypoxylon. It is suggested that the coloured papillate species e.g.H. multiforme are more closely related toH. fragiforme and members of the Hypoxylon section than to non-coloured papillate species as indicated in the current classification of the genus.The relationships betweenHypoxylon, Daldinia andRosellinia are discussed.  相似文献   

11.
Relationships amongCalamagrostis longiseta var.longiseta, C.l. var.longe-aristata andC. fauriei, which are principally at the 2n=28 chromosome level, were studied mainly on the basis of population samples. The populations comprised (1) “pure” populations of each ofC.l. longiseta, C.l. longe-aristata andC. fauriei and (2) populations showing a gradation fromC.l. longiseta toC. fauriei via the intermediateC.l. longearistata and fromC.l. longiseta toC.l. longe-aristata. Hybridization betweenC.l. longiseta andC. fauriei was estimated to be ultimately related to the geneses of the population structures detected, and it was concluded thatC.l. longe-aristata must be of hybrid origin betweenC.l. longiseta andC. fauriei. Populations showing a gradation fromC.l. longiseta toC.l. longe-aristata were regarded to have been brought about by the extinction ofC. fauriei from the hybridizing population coupled with the change of environments and also by the secondary contact betweenC.l. longiseta and plants ofC.l. longe-aristata migrating from the area that produced it. No significant reduction of pollen fertility and seed productivity was found inC.l. longe-aristata. Based on the results of population analyses, the delimitation of the taxa concerned was made clearer. The examination of herbarium specimens showed that the range ofC.l. longe-aristata considerably exceeds the overlapping area of the present ranges ofC.l. longiseta andC. fauriei. The three taxa were deviated ecologically, and “pure” populations ofC.l. longe-aristata were found on several damp subalpine fields in central and northern Honshu that seemed to represent the most suitable niche for this taxon. It was estimated thatC.l. longe-aristata would evolve into a new good species if the future organism-environment interactions are favorable for it.  相似文献   

12.
The aim of the work was to determine the effect of exposing ovine bronchoalveolar macrophages (BAM)in vivotoPasteurella haemolyticaand/orBordetella parapertussison the subsequent uptake and killing ofP. haemolyticaby these cellsin vitro. Exposurein vivotoP. haemolyticadid not affect the uptake ofP. haemolyticaby BAMin vitrobut reduced (P< 0·05) the intracellular killing of bacteria. Exposurein vivotoB. parapertussishad no significant effect on either the uptake of killing ofP. haemolytica in vitro. However, sequential exposurein vivotoB. parapertussisandP. haemolyticareduced both the ingestion (P< 0·05) and killing (P< 0·001) ofP. haemolytica in vitro. These results indicate that exposure toP. haemolyticacompromised the bacterial killing mechanisms of BAM and that synergy betweenB. parapertussisandP. haemolyticareduced the ability of BAM to ingest bacteria.  相似文献   

13.
Urbatsch  Lowell E.  Turner  B. L. 《Brittonia》1975,27(4):348-354

The genusSabazia is expanded to include the genusTricarpha, Calea palmeri, and several newly described taxa,S. tridacoides var.tridacoides and var.latifolia, S. palmeri var.lancifolia, andS. longiradiata. Comparative studies of several morphological features suggest thatSabazia is most clearly related toSelloa andGalinsoga. Karyological data reinforce this observation: inSelloa andGalinsoga x = 8 whereas inSabazia x = 4 andn = 4, 8, 16, or 24. Several species ofCalea are very similar toSabazia in floral features and may be of close phyletic affinity, but most species ofCalea differ conspicuously, suggesting more remote relationships. Other taxa in the Galinsoginae apparently fairly closely allied toSabazia includeOteiza andTridax.

  相似文献   

14.
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   

15.
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   

16.
The interspecific relationships of the following nine forms ofSaguinus were analyzed applying the multivariate analysis to the cranial measurements;S. oedipus, S. geoffroyi, S. leucopus, S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. midas midas, andS. midas niger. Penrose's size distance was used to express the size factor among the nine forms; and for the shape factor, Q-mode correlation coefficients were utilized. The shape distance betweenS. oedipus andS. geoffroyi was almost equal to that betweenS. nigricollis andS. fuscicollis which are recognized as different species based on biogeographical evidence. Furthermore, the Penrose's size distance betweenS. oedipus andS. geoffroyi was quite large. Therefore, the results of this study support the hypothesis thatS. oedipus andS. geoffroyi are valid species. The analysis of the phylogenetic relationships among the nine forms was based on the shape factor only. The forms were divided into two main clusters: (1)S. oedipus, S. geoffroyi, andS. leucopus; (2)S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. midas midas, andS. midas niger. In the former cluster,S. oedipus was more closely related toS. geoffroyi than either was toS. leucopus. The latter cluster was subdivided in two subclusters based on the degree of their affinity: (2a)S. nigricollis, S. fuscicollis, S. labiatus, andS. mystax; and (2b)S. midas midas andS. midas niger. In the former subcluster, [S. nigricollis, S. fuscicollis] and [S. labiatus, S. mystax] were classified into clusters, respectively. The ancestor of theS. nigricollis group differentiated intoS. oedipus, S. geoffroyi, andS. leucopus with the narrowing of the maxilla in the facial region, andS. midas midas andS. midas niger with the downward movement of rhinion.  相似文献   

17.
The relationship ofAmbrosia (ragweed) andFranseria has long been debated. Their treatment as separate genera has been repeatedly challenged. In this study, chloroplast DNA restriction site variation was examined for species from bothAmbrosia andFranseria as well as taxa from the closely related genusHymenoclea. The chloroplast genomes of members of these three genera were examined using 21 restriction endonucleases and the restriction mutations were used to construct phylogenetic trees. Wagner and Dollo parsimony as well as weighted parsimony were employed to compare the different phylogenies. The results support a close relationship betweenAmbrosia andFranseria, but indicate that the two groups are well separated. Compared toFranseria, Ambrosia is a much more strongly supported group, and the results indicate thatHymenoclea is closer toFranseria than toAmbrosia. The cpDNA phylogeny was used as a framework to examine evolutionary trends in morphology and secondary chemistry.  相似文献   

18.
Evidence has been obtained for recombination betweenH-3 and the closely linkedIr-2 locus, which controls the antibody response toEa-1 antigens. The data suggest thatIr-2 maps close toH-3, betweenH-3 andH-13. The YBR strain has been found to possess anH-3 allele not previously reported. A comparison has been made between the degree of polymorphism of histocompatibility loci and that which involves electrophoretically detectable protein variants.  相似文献   

19.
Both diploid and tetraploid experimental interspecific hybrids betweenRanunculus silerifolius (2x) andR. chinensis (2x) exhibit normal bivalent pairing. However, microspores of diploid hybrids do not undergo mitosis and their pollen grains are highly sterile, whereas tetraploid hybrids form good pollen grains after microspore division. Evidence is forwarded for the assumption thatR. cantoniensis (4x) has originated by hybridization between these two diploid parental species and by polyploidization of the diploid hybrids. Parallelisms between the different karyotypes ofR. cantoniensis (4x) andR. silerifolius (2x) suggest that the former is a species of polyphyletic origin.  相似文献   

20.
AFLP markers were used to assess genetic relationships among Cicer species with distribution in Turkey. Genetic distances were computed among 47 Cicer accessions representing four perennial and six annual species including chickpea, using 306 positions on AFLP gels. AFLP-based grouping of species revealed two clusters, one of which includes three perennial species, Cicer montbretii, Cicer isauricum and Cicer anatolicum, while the other cluster consists of two subclusters, one including one perennial, Cicer incisum, along with three annuals from the second crossability group (Cicer pinnatifidum, Cicer judaicum and Cicer bijugum) and the other one comprising three annuals from the first crossability group (Cicer echinospermum, Cicer reticulatum and Cicer arietinum). Consistent with previous relationship studies in the same accession set using allozyme and RAPD markers, in AFLP-based relationships, C. incisum was the closest perennial to nearly all annuals, and C. reticulatum was the closest wild species to C. arietinum. Cluster analysis revealed the grouping of all accessions into their distinct species-clusters except for C. reticulatum accessions, ILWC247, ILWC242 and TR54961; the former was found to be closer to the C. arietinum accessions while the latter two clustered with the C. echinospermum group. Small genetic distance values were detected among C. reticulatum accessions (0.282) and between C. reticulatum and C. arietinum (0.301) indicating a close genetic similarity between these two species. Overall, the AFLP-based genetic relationships among accessions and species were congruous with our previous study of genetic relationships using allozymes. The computed level of AFLP variation and its distribution into within and between Cicer species paralleled the previous report based on RAPD analyses. AFLP analysis also confirmed the presence of the closest wild relatives and previous projections of the origin of chickpea in southern Turkey. Results presented in this report indicate that AFLP analysis is an efficient and reliable marker technology in determination of genetic variation and relationships in the genus Cicer. Obviously, the use of AFLP fingerprinting in constructing a detailed genetic map of chickpea and cloning, and characterizing economically important traits would be promising as well.Communicated by P. Langridge  相似文献   

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