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1.
Phylogenetic relationships within the tribe Antirrhineae (Scrophulariaceae) are analysed and discussed on the basis of parsimony analyses of morphological andndhF gene sequence data. The results indicate that the tribe Antirrhineae consists of four major groups of genera, theAnarrhinum clade, theGambelia clade, theMaurandya clade, and theAntirrhinum clade. TheAnarrhinum clade, consisting of the Old World bee-pollinated generaAnarrhinum andKickxia, is sister to the rest of the tribe. TheGambelia clade consists of the New World generaGambelia andGalvezia, which are very closely related and pollinated by hummingbirds. TheMaurandya clade consists of one subclade includingMaurandya and a number of related bee- or hummingbird-pollinated New World genera and another subclade with the Old World bee-pollinated generaAsarina andCymbalaria. TheAntirrhinum clade consists mainly of bee-pollinated Old World genera, such asAntirrhinum, Linaria, Chaenorhinum, and their segregates, but also includes the New World generaMohavea andHowelliella, of which the latter is known to be partly pollinated by hummingbirds. It is concluded that hummingbirdpollination has evolved independently within Antirrhineae at least three times from bee-pollinated ancestors.  相似文献   

2.
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   

3.
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   

4.
A phylogenetic analysis of 25 species, representing eight genera of theRubieae tribe (Rubiaceae), has been made using the DNA sequence of the chloroplastatp B-rbc L intergene region. Six tropical genera from other tribes ofRubiaceae have been used as outgroups. Whatever the method of analysis (distance, parsimony or maximum likelihood), five groups are clearly separated and described as informal clades. Their relative relationships are not clearly resolved by the parsimony analysis, resulting in eight equally parsimonious trees, 327 steps long, with a consistency index (CI) of 0.749 (excluding uninformative sites). TheRubieae tribe appears monophyletic from the data available. Some new and partly unexpected phylogenetic relationships are suggested. The genusRubia forms a separate clade and appears to be the relatively advanced sister group of the remaining taxa. TheSherardia clade also includes the generaCrucianella andPhuopsis. Galium sect.Aparinoides appears closely attached to theAsperula sect.Glabella clade. The remaining taxa ofGalium are paraphyletic:Galium sect.Platygalium (in theCruciata clade) is linked to the advanced generaCruciata andValantia; the more apomorphic groups ofGalium form theGalium sect.Galium clade, including the perennial sectionsGalium, Leiogalium, andLeptogalium as well as the annual (and possibly polyphyletic) sect.Kolgyda.  相似文献   

5.
Taxonomy of thePresbytis melalophos group in Sumatera has been based solely on the distinction in the pelage coloration and has been a subject of controversy. In the present study, extensive field observations were undertaken. Three species, i. e.P. melalophos, P. thomasi, andP. femoralis, are recognized in Sumatera based on the cranial morphology, pelage coloration, and vocalization. Subspecies of each species are revised, a new classification is proposed, and a new subspecies,Presbytis melalophos bicolor, is described. A detailed distribution map of species and subspecies is presented. No sympatry occurs between the species. Finally, a cladistic analysis is presented for the three species, based on the cranial characters; the branching sequence is first between theP. melalophos clade and theP. femoralis- P. thomasi clade and second between theP. femoralis clade and theP. thomasi clade.  相似文献   

6.
Parsimony and maximum likelihood analyses of combinedtrnL (UAA) 5 exon —trnF (GAA) andrps4 exon cpDNA, and 18S nrDNA sequences of 60 arthrodontous moss taxa indicate strong support for the monophyly of a clade containing theSplachnineae, Orthotrichineae, and diplolepideous alternate sub-orders. A clade including theSplachnineae, Meesiaceae andLeptobryum (Bryaceae) is similarly well supported and forms the sister group to a clade comprising theOrthotrichineae and the other diplolepideous alternate mosses. Within this latter clade a number of well supported lineages are identified, but relationships among these remain poorly resolved. These analyses indicate that the Splachnaceous and Orthotrichaceous peristomes have been independently derived from an ancestral perfect bryoid peristome.  相似文献   

7.
The serological investigations support the opinion ofJanchen (1942) to combine the generaBunias, Isatis, andSisymbrium in the tribeSisymbrieae; Cheiranthus, Erysimum, andMatthiola in the tribeHesperideae; andBrassica, Crambe, Sinapis, andSuccowia in the tribeBrassiceae. They further underline the central position of theSisymbrieae and the isolated position of theHeliophileae. In accordance withEigner (1973) theBrassiceae are placed closer to theSisymbrieae than inJanchen; the same holds for thePringleeae. No serological justification could be found to uniteArabis andBarbarea in the tribeArabideae, andAlyssum andLunaria in theAlysseae. From the antigen-systems used among the representatives ofJanchen's Lepidieae the generaLepidium andNeslia show remarkable correspondence both toCamelina andThlaspi, but not toCochlearia which appears distant fromCamelina andThlaspi also.
Teil 1/Part 1.  相似文献   

8.
Complete sequences for the 18S-rRNA gene of 22 bryophytes (12 completely new) were determined and used to construct phylogenetic trees. The evaluation of sequence data according to the maximum parsimony principle (PAUP 3.1.1) and the neighbor-joining method (MEGA) results in similar phylogenetic trees in which theBryopsida appear as a sister group to theJungermanniopsida, and both together as a sister group to theMarchantiopsida. Among theMarchantiopsida, theSphaerocarpales diverge early as a separate clade. TheMetzgeriales andJungermanniales are monophyletic. They belong to one clade and cannot be separated by either method of evaluation.  相似文献   

9.
Taxonomic relationships amongst the genera of the southern African tribesPodalyrieae andLiparieae are discussed. Data gained from morphological, cytological and chemical investigations are analyzed cladistically to determine relationships. The genusCadia (tribeSophoreae) is included in the investigation to establish whether it should be transferred to thePodalyrieae. The results clearly indicate that thePodalyrieae andLiparieae are monophyletic and that they should be united, but thatHypocalyptus andCadia should be excluded. Within the monophyletic group, there are two distinct subclades each supported by three apomorphies. The results also show that there is a strong sister relationship betweenAmphithalea andCoelidium. In the taxonomic treatment theLiparieae are placed into synonymy under thePodalyrieae and two subtribes are recognized. A key to the genera in the tribe is given, followed by a synopsis of the genera.  相似文献   

10.
The placement of a recently discovered South American monotypic genus,Pseudomonotes tropenbosii, in subfam.Monotoideae (Dipterocarpaceae) extends the geographical range of the subfamily from Africa to the Neotropics. Although morphological and anatomical evidence suggest similarities betweenPseudomonotes andMonotes, the close alliance of these two genera was questionable due to their disjunct distribution and a lack of phylogenetic analysis. In the present study, we reconstructed the phylogeny ofPseudomonotes and other putatively related taxa usingrbcL sequence data. The analysis ofrbcL sequences of 20 taxa belonging to 15 genera and eight families recovered a single most parsimonious tree. The genusSarcolaena (Sarcolaenaceae) formed a clade sister to the monophyleticDipterocarpaceae clade.Monotes andPseudomonotes formed a strongly supported group, sister to the monophyletic clade withPakaraimaea and the remaining Asiatic dipterocarp species studied. The study strongly supports the placement ofPseudomonotes within subfam.Monotoideae of theDipterocarpaceae.  相似文献   

11.
The phylogenetic relationships of the angiosperm generaByblis andRoridula have been the subject of ongoing taxonomic controversy. Twenty-eight taxa of varying degrees of alleged relationship, including 3 members of theWinteraceae (as an outgroup), were investigated using partial sequences of 18S rRNA (small subunit) and also compared against the morphological data set fromHufford's (1992) cladistic treatment of 80 members of theRosidae-Asteridae. The morphological analysis placed the two genera in a clade with theSarraceniaceae in theCorniflorae-Asterid group as a sister taxon to anEricales-Hydrangeales clade. The 18S rRNA analysis supports the recently publishedrbcL DNA analysis ofAlbert & al. (1992), withRoridula joined to taxa in the lowerRosidae, butByblis joining instead to members of theAsteridae near theSolanaceae. Comparisons for congruence between the three analyses placeByblis in the higher Asterid group near theSolanaceae, andRoridula possibly nearer theSarraceniaceae andEricales. These results imply that the traditional morphological characters used to relate the two genera are possibly the result of convergence towards similar ecological and life-history strategies rather than synapomorphies.  相似文献   

12.
13.
A parsimony analysis of DNA sequences of the chloroplast-encoded generbcL from twelve members of theAcanthaceae s.l., including members of the sometimes segregateThunbergioideae andNelsonioideae, and other families in theBignoniales sensuThorne (1992) is presented. The results largely agree with the classification of theAcanthaceae presented byBremekamp (1965) andThorne (1992) and supportNelsonioideae as a sister group to the rest of theAcanthaceae. Thunbergioideae are placed as a sister toAcanthaceae s.str.Acanthus andAphelandra, both representatives ofAcanthoideae, form a sister group toRuellioideae. An analysis of branch support found that many branches throughout theBignoniales are weakly upheld. This points to the need for further studies in the group using more sequences ofrbcL as well as other data. None of the families ofBignoniales as presently circumscribed (includingAcanthaceae s.l.) were strongly supported, although the larger clade containing the families of theBignoniales was robust.  相似文献   

14.
Total DNA was extracted from 55 species of theLeguminosae (including 29 species ofLupinus). The chloroplast generbcL and the ITS 1 + 2 regions of nuclear RNA genes were amplified by polymerase chain reaction (PCR) and sequenced directly. The sequences obtained were evaluated with character state (Maximum Parsimony) and distance methods (Neighbour Joining). Phylogenetic trees obtained with both data sets and methods are mostly congruent.Genisteae andCrotalarieae are sister groups and share ancestry with theThermopsideae/Podalyrieae. The genusLupinus, which forms a monophyletic clade within theGenisteae, shows a distinct Old-New World disjunction and appears to be divided into several more or less distinct groups: (1) The species from the eastern part of South America. (2) The homogeneous rough-seeded group (Scabrispermae) of the Old World species which is well distinguished from the smooth-seeded group (Malacospermae). (3) Within the rather heterogeneous smooth-seeded lupins a smaller subgroup withL. angustifolius, L. hispanicus andL. luteus is recognized. (4) Also separated are North American lupins and South American species with a western distribution. Genetic distances imply that the genusLupinus evolved during the last 12–14 million years, ruling out the hypothesis that the present Old-New World disjunction can be interpreted as a result of the continental drift. The genetic data suggest an origin in the Old World and an independant colonisation of the Eastern parts of South America as opposed to North America and the Western parts of South America.  相似文献   

15.
A mutation in theCENTRORADIALIS (CEN) gene ofAntirrhinum and in theTERMINAL FLOWER 1 (TFL1) gene ofArabidopsis causes their indeterminate inflorescence to determinate. We clonedCEN/TFL1 homologs fromNicotiana tabacum, the wild-type of which has a determinate inflorescence. TheCEN gene was expressed in the inflorescnece meristem and kept its inflorescence meristem identity, whereas the tobacco homolog (NCH) was expressed at a low level throughout the plant’s development. AlthoughCEN andNCH are highly homologous genes, they may have been recruited to different developmental functions during their evolution. TwoNCH genes are derived from amphidiploidN. tabacum, but both of them hybridized with its diploid parents,N. sylvestris andN. tomentosiformis. Southern blotting, and the genomic organization ofTFL1 inArabidopsis revealed that anotherCEN homolog exists in the genome ofArabidopsis. These results suggest that there are two copies of theCEN homolog per diploid plant. The extended abstract of a paper presented at the 13th International Symposium in Conjugation with Award of the International Prize for Biology “Frontier of Plant Biology” These two authors contributed to this work equally.  相似文献   

16.
Chloroplast DNA (cpDNA) restriction site analysis was used to assess relationships among samples of Eupatorieae from eastern North America. A total of 270 cpDNA variants was recorded from 35 species using 13 restriction enzymes. Phylogenetic analysis usingGalinsoga, Flaveria, andHelianthinae as outgroups indicated that samples ofAgeratina, Hofmeisteria, Mikania, andStevia, each of which have relatively high base chromosome numbers, formed an unresolved basal polytomy. The remaining samples examined formed a well-supported clade, within which there was a split betweenBrickellia, which hasx = 9, and a number of genera withx = 10. Within thex = 10 clade, there was an unresolved trichotomy, with one group ofAgeratum, Conoclinium, Fleischmannia, andCritonia, a second ofLiatris andTrilisa, and a third ofEupatorium s.s. Within theEupatorium s.s. clade there were three further clades, withE. sect.Verticillata diverging first, and a subsequent split between species originating from North America and those from Asia. The cpDNA restriction site data provided support for a relatively narrow interpretation ofEupatorium, and indicated that a high chromosome base number is plesiomorphic for Eupatorieae.  相似文献   

17.
A skull fragment (VM-0) from Orce, Granada, Spain, dated palaeomagnetically at about 1.6 Myr, is thought by some palaeontologist to be hominid, while others maintain it is equid. If hominid, it would be by far the oldest evidence ofHomo in Europe. Immunological studies on residual albumin in this fossil were carried out independently, and with different immunological methods, at the University of California, San Francisco (radioimmunoassay), and at the University of Granada, Spain (enzyme immunoassay). Other fossils attributed to hominids also studied wereVM1960 from Venta Micena, andCV-1 from Cueva Victoria, Murcia, Spain. Undisputed equid and bovid fossils from the same deposits and dated to a similar period as the Orce skull were also analyzed. Our results showed that species-specific albumin can be detected in 1.6 Myr-old hominid, equid and bovid fossils. The albumin from the Orce skull fragment and fromVM-1960 was immunologically closer to human albumin. These findings support the contention that theVM-0 andVM-1960 are hominid and that members of the genusHomo occupied southern Spain 1.6 Myr ago.  相似文献   

18.
A cytological analysis of 37 experimental interspecific hybrids withinEpilobium sect.Epilobium, involving 23 taxa, has indicated that the CC chromosome arrangement differs from BB by a single reciprocal translocation and was probably, like AA and DD, derived from it. Preliminary results suggest that the CC arrangement may characterize the AsianE. cephalostigma andE. platystigmatosum, which do not closely resemble the species in which it had earlier been detected. The BB arrangement is shown to occur in all North American species of theE. palustre group, includingE. oregonense. Direct evidence on chromosome arrangement is now available for some 85 of the approximately 185 species of the section, and may be inferred for at least 25 more.  相似文献   

19.
Cladistic relationships of epacrids and vaccinioids (Ericaceae) are investigated using nucleotide sequence data from the chloroplast encodedmatK gene. Sequences of 56 taxa were aligned and analyzed using parsimony methods. Results show thatVaccinioideae as currently recognized are not monophyletic. The epacrids are sister to a clade that includes theLyonia group, theGaultheria group, and theVaccinieae. Arbutus andPyrola branch early inEricaceae, before the rhododendroid group.Enkianthus is sister to the remainingEricaceae (includingEpacridaceae).Vaccinieae are strongly supported as monophyletic, butVaccinium andAgapetes are polyphyletic.  相似文献   

20.
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