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1.
The closely related species, diploid Anthoxanthum alpinum Á. Löve et D. Löve and tetraploid Anthoxanthum odoratum L., have distinct distributions: A. alpinum is an arctic-alpine species, while A. 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 with A. alpinum, the other with A. 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 of A. 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 for A. 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 of A. odoratum in the “alien” locality. We conclude that A. alpinum could have been limited in extending its distribution into the area of A. odoratum by the presence of strong competitors, while A. 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, and Campanula, 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 that Hanabusaya is more closely allied to Adenophora than to Campanula or Symphyandra. The phylogenetic affinity of Hanabusaya and Adenophora is supported by a 100% bootstrap value and a high decay index (13). The average sequence divergence value (Kimura’s 2-parameter
method) between Hanabusaya and the Adenophora species is 2.58. The value is significantly (about ten times) lower than the ones observed between Hanabusaya and the species of Campanula (average of 23.52) and between Hanabusaya and Symphyandra (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 in Phleum species. The total DNA isolated from diploid species P. alpinum and P. bertolonii was partially digested with Sau3AI and cloned using pUC19 as a vector to an E. coli strain DH5mcr. A partial genomic DNA library consisting of 3030 colonies for the genome of P. alpinum and one consisting of 3240 colonies for the genome of P. bertolonii were constructed. Twelve hundred and thirty colonies from the DNA library of P. alpinum and 1320 from that of P. bertolonii were respectively blotted to membrane filters and hybridized to the total genomic probes from these two species. Eight clones specific to P. alpinum and 13 specific to P. 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 to P. alpinum and 3 specific to P. bertolonii were used as probes to hybridize the EcoRI-digested DNA samples from four species, P. alpinum, P. bertolonii, P. pratense and P. montanum, on Southern blot. The results from these hybridization experiments showed that all 3 P. bertolonii-specific probes and 2 of the 3 P. alpinum-specific probes hybridized to the DNA of P. 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 autotetraploid A. alpinum was found in France. In the A. 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 and Lipiniella share several apparantly apomorphic features of the mouth-part structure, however adults of Lipiniella show possible relationships to Demeijerea and Chironomus. In order to assist in refining the relationships of Axarus to Lipiniella the karyotype of Axarus festivus was determined and compared to the karyotypes of Lipiniella arenicola and L. moderata. Larvae of A. 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 from L. arenicola in chromosome number (2n=6), however homologous sections of all chromosomes were identified. Inversions were detected in the Ist, IInd and IIIrd chromosomes of A. festivus relative to L. 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 for L. 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 between A. festivus and L. arenicola. However, we did not find evidence for similarity of A. festivus to L. moderata, which supports the previous conclusions by Kiknadze
et al. (1989) regarding L. arenicola and L. moderata. 相似文献
6.
Pinus hakkodensis has been considered as a hybrid between P. pumila and P. 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 between trnL(UAA)3′ exon and trnF(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 of P. parviflora var. pentaphylla. Furthermore, some individuals classified on the basis of needle morphology as belonging to P. pumila in this mountain region showed the SSCP pattern of P. parviflora var. pentaphylla. This may suggest that pollen-mediated uni-directional introgression from P. parviflora var. pentaphylla to P. pumila occurs in the Tanigawa Mountains. 相似文献
7.
The sex-specific growth factors produced by the a and mating types of Kluyveromyces lactis were examined for interspecies cross-reactivity on growing cells of Kluyveromyces aestuarii and Kluyveromyces delphensis. Taxonomically, K. aestuarii is closely related to K. lactis; K. delphensis is more distantly related. Reciprocal growth responses occurred between K. aestuarii and the a mating type of K. lactis; no response was evident between K. delphensis and either sex of K. lactis. 相似文献
8.
Morphological variation was analyzed in the endangered Betula uber and sympatric dark-barked tree birches, B. lenta and B. 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, that B. uber is more similar to B. lenta than to B. alleghaniensis, that intermediates between B. uber and B. lenta do not occur, and that leaves are necessary for absolute separation of B. uber from B. lenta because of overlap of fruit characters. Field observations of the bark indicate no differences between B. uber and B. lenta while those of growth form suggest that B. uber may have a more compact crown than B. lenta. The evidence presented here supports an alliance of B. uber with the dark-barked tree birches (series Costatae). 相似文献
9.
Theligonum cynocrambe and 13 species of Rubiaceae contain S-type sieve-element plastids, wide-spread in Dicotyledons. Alignment of Theligonum to Caryophyllales ( Centrospermae), especially Phytolaccaceae, is unlikely, because this order is characterized by specific P-type plastids. SEM investigations show the pollen exine of Theligonum to be microreticulate, with additional supratectate spinules. Asperula and other genera of the tribe Rubieae have a tectum perforatum (punctitegillate sexine), also with supratectate verrucae or spinulae.—Thus ultrastructure suggests (but not definitely proves) relationships between Theligonum and Rubiaceae, while affinities between Theligonum and Caryophyllales are excluded. 相似文献
10.
Numerical analysis has resulted in a division of the coloured and non-coloured species of Hypoxylon. It is suggested that the coloured papillate species e.g. H. multiforme are more closely related to H. fragiforme and members of the Hypoxylon section than to non-coloured papillate species as indicated in the current classification of the genus.The relationships between Hypoxylon, Daldinia and Rosellinia are discussed. 相似文献
11.
Relationships among Calamagrostis longiseta var. longiseta, C.l. var. longe-aristata and C. 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 of C.l. longiseta, C.l. longe-aristata and C. fauriei and (2) populations showing a gradation from C.l. longiseta to C. fauriei via the intermediate C.l. longearistata and from C.l. longiseta to C.l. longe-aristata. Hybridization between C.l. longiseta and C. fauriei was estimated to be ultimately related to the geneses of the population structures detected, and it was concluded that C.l. longe-aristata must be of hybrid origin between C.l. longiseta and C. fauriei. Populations showing a gradation from C.l. longiseta to C.l. longe-aristata were regarded to have been brought about by the extinction of C. fauriei from the hybridizing population coupled with the change of environments and also by the secondary contact between C.l. longiseta and plants of C.l. longe-aristata migrating from the area that produced it. No significant reduction of pollen fertility and seed productivity was found in C.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 of C.l. longe-aristata considerably exceeds the overlapping area of the present ranges of C.l. longiseta and C. fauriei. The three taxa were deviated ecologically, and “pure” populations of C.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 that C.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 vivoto Pasteurella haemolyticaand/or Bordetella parapertussison the subsequent uptake and killing of P. haemolyticaby these cells in vitro. Exposure in vivoto P. haemolyticadid not affect the uptake of P. haemolyticaby BAM in vitrobut reduced ( P< 0·05) the intracellular killing of bacteria. Exposure in vivoto B. parapertussishad no significant effect on either the uptake of killing of P. haemolytica in vitro. However, sequential exposure in vivoto B. parapertussisand P. haemolyticareduced both the ingestion ( P< 0·05) and killing ( P< 0·001) of P. haemolytica in vitro. These results indicate that exposure to P. haemolyticacompromised the bacterial killing mechanisms of BAM and that synergy between B. parapertussisand P. haemolyticareduced the ability of BAM to ingest bacteria. 相似文献
13.
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 of Cathaya, a relic genus of the Pinaceae, was discussed based on the rbcL gene sequence. The sequence data were analysed with PAUP and MEGA programs. The great genetic distance value between Cathaya and any other genus of the Pinaceae showed that Cathaya was a distinct and isolated genus. The most parsimonious Fitch tree and neighbor-joining tree showed that Cathaya was distantly related to the clade comprising Abies, Keteleeria, Pseudolarix and Tsuga, and a sister group relationship between Cathaya and Pinus was weakly supported. Pseudotsuga is closely related to Larix. In the Abies-Keteleeria-Pseudolarix-Tsuga clade, Abies has a close relationship to Keteleeria while Pseudolarix is relatively closely related to Tsuga. 相似文献
15.
Although several investigations have been made from different viewpoints, the classification or interspecific relationships
of Saguinus still remain uncertain.
In the present study, we applied multivariate analysis methods to dental measurements of part of Saguinus populations of sufficient sample size and obtained the following conclusions. Saguinus can be classified into two main groups: one consists of S. oedipus and S. leucopus, and the other of S. fuscicollis, S. nigricollis, S. labiatus, and S. mystax. Concerning the former group, the two subspecies of S. oedipus, S. o. oedipus, and S. o. geoffroyi, show a close affinity with each other and also a close relationship to S. leucopus, while the latter group consists of two subgroups of species, one including S. fuscicollis and S. nigricollis, and the other including S. labiatus and S. mystax. The biological distance between S. oedipus oedipus and S. o. geoffroyi is slightly larger than that between the pairs of S. fuscicollis and S. nigricollis and of S. labiatus and S. mystax. Factor analysis revealed significant factors which could explain the differences among the seven male Saguinus populations.
Taking all the results into account, it seems necessary to reconsider the phylogenetic relationships within the genus Saguinus. 相似文献
16.
The interspecific relationships of the following nine forms of Saguinus 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, and S. 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 between S. oedipus and S. geoffroyi was almost equal to that between S. nigricollis and S. fuscicollis which are recognized as different species based on biogeographical evidence. Furthermore, the Penrose's size distance between S. oedipus and S. geoffroyi was quite large. Therefore, the results of this study support the hypothesis that S. oedipus and S. 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, and S. leucopus; (2) S. nigricollis, S. fuscicollis, S. labiatus, S. mystax, S. midas midas, and S. midas niger. In the former cluster, S. oedipus was more closely related to S. geoffroyi than either was to S. leucopus. The latter cluster was subdivided in two subclusters based on the degree of their affinity: (2a) S. nigricollis, S. fuscicollis, S. labiatus, and S. mystax; and (2b) S. midas midas and S. midas niger. In the former subcluster, [ S. nigricollis, S. fuscicollis] and [ S. labiatus, S. mystax] were classified into clusters, respectively.
The ancestor of the S. nigricollis group differentiated into S. oedipus, S. geoffroyi, and S. leucopus with the narrowing of the maxilla in the facial region, and S. midas midas and S. midas niger with the downward movement of rhinion. 相似文献
17.
The relationship of Ambrosia (ragweed) and Franseria 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 both Ambrosia and Franseria as well as taxa from the closely related genus Hymenoclea. 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 between Ambrosia and Franseria, but indicate that the two groups are well separated. Compared to Franseria, Ambrosia is a much more strongly supported group, and the results indicate that Hymenoclea is closer to Franseria than to Ambrosia. 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 between H-3 and the closely linked Ir-2 locus, which controls the antibody response to Ea-1 antigens. The data suggest that Ir-2 maps close to H-3, between H-3 and H-13. The YBR strain has been found to possess an H-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 between Ranunculus silerifolius (2x) and R. 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 that R. cantoniensis (4x) has originated by hybridization between these two diploid parental species and by polyploidization of the diploid hybrids. Parallelisms between the different karyotypes of R. cantoniensis (4x) and R. 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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