摘要:

In our previous works (MANENet al., Pl. Syst. Evol.190: 195–211, 1994; NATALIet al., Ann. Missouri Bot. Gard.82: 428–439, 1995) we had presented a phylogenetic analysis of 39 species of the tribeRubieaeand of 15 taxa belonging to 12 other tribes of Rubiaceae using the DNA sequence of the chloroplastatpB–rbcL intergene region. This has allowed a precise and useful delimitation of the tribeRubieae,which is clearly monophyletic and characterised by a 50–bp deletion. The clades recognised withinRubieaeare often in agreement with classical taxonomic views, but also partly contradict traditional groupings. In this paper we extend these data by adding the sequences of 9 moreRubieaetaxa, belonging to 6 different genera, and we analyse in detail the taxonomic implications of these results in the view of a complete revision of the tribeRubieae.The results of our phylogenetic study, based on sequence data for a chloroplast intergene region, show the great taxonomic potential of this new method. TheatpB–rbcL data give useful suggestion for taxonomic positions of genera and species with uncertain affiliations(Theligonum cynocrambe, Galium odoratum, Asperula purpurea),they can support some suspected affinities among earlier distantly placed taxa(Galiumsect.Aparinoidesnear toAsperulasect.Glabella),in other cases they open up new taxonomic perspectives(Galiumsect.Platygaliumin the same clade asValantiaandCruciata;close affinity ofGalium corsicumwith theG. parisiense–G. divaricatumgroup) and they can even give new arguments for the creation of some new infraspecific taxa(G. lucidumgroup). The molecular studies should be considered as an useful framework for the taxonomic revisions of plant groups, stimulating the botanists to investigate more deeply some possibly neglected biosystematic characters. Only multidisciplinary co–operation will result in real progress concerning our systematic and phylogenetic understanding of the vegetal world.

ISSN:0017-0070    

DOI:10.1080/11263509509436102

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0017-0070    

DOI:10.1080/11263509509436103

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0017-0070    

DOI:10.1080/11263509509436104

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Out of 94 grass genera with 318 species in Bulgaria, 294 species and 60 subspecies are studied karyologically on the basis of 722 populations. Hybridization, polyploidy and to a lower extent apomixis and aneuploidy, restricted to dysploidy are the evolutionary mechanisms acting within the grass family in Bulgarian flora. Sixteen polyploid or polyploidaneuploid series have been established which reveals the process of local speciation, particularly in the genera ofElymus, Bromus, Brachypodium, Poa, Festuca, Avena, Koeleria, StipaandSesleria.The diploid level is presented by 305 cytodemes, tetraploids are 234, hexaploids - 80, octoploids - 16 and decaploids - 10. The percentage of grass polyploidy ranks 56.50%, mainly consisted of tetraploids - 72.45%.

ISSN:0017-0070    

DOI:10.1080/11263509509436105

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The genusViolasect.Melaniumis represented in Sicily by six well defined species. The taxonomic range of two additional taxa, whose areals are restricted to isolated mountains (Rocca Busambra and Pizzuta Mt.), south of Palermo, was hitherto unclear. Morphological and caryological investigations showed that they can be treated as distinct species, which are here described. TheViolawith constantly blue flowers and 2n= 52 chromosomes of Rocca Busambra is namedViola tineorumand the other one, with constantly yellow flowers and 2n= 40 chromosomes of the Pizzuta Mt. is namedViola ucriana.Both are named according to the famous Sicilian botanists Giuseppe and Vincenzo Tineo and Bernardino d' Ucrìa.

ISSN:0017-0070    

DOI:10.1080/11263509509436106

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0017-0070    

DOI:10.1080/11263509509436107

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The aim of this research is to represent some of the latest results form the karyological study ofErysimum drenowskii, E. comatumand allied species and members ofE. diffusumgroup in Bulgaria. Some ideas on the evolutionary history within the genus are suggested.

ISSN:0017-0070    

DOI:10.1080/11263509509436108

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

To obtain better insight in evolutionary processes, data on genetic diversity are compared with data obtained by more traditional biosystematic methods. Altogether, ten isozymes in 25 populations ofLobularia,Cruceferac, from Spain, Morocco, the Salvage Islands, the Canary Islands and the Cape Verde Islands were screened by starch gel electrophoresis. Genetic identities between pairs of species were low: 0.582 forcanariensislibyca,0.603 forcanariensis-maritima,and 0.403 forlibyca-maritima.These species are biological species, i.e. isolated by strong internal crossing barriers. The isozyme data indicate that speciation is an old event in the genus. The nine subspecies of theL. canariensiscomplex are interfertile and isolated by ecogeographical barriers. Among the subspecies, the genetic identities ranged from 0.476 to 0.846, with a mean identity of 0.734 for all pairs. Among 22 populations ofL. canariensis,irrespective of taxon, the identities ranged from 0.456 to 0.961, with a mean of 0.717. In comparison, the identity for two populations ofL. maritima,one from Spain and one from Morocco, was 0.753. Thus genetic identities were higher within than among species but theL. canariensiscomplex showed much infraspecific genetic diversity. Genetic distances matched geographic distances to some extent, with a northern and a southern gene pool. In the Canaries, however, genetic distances did neither correspond to geographic distances nor to subspecies ofL. canariensis,indicating some gene flow between populations, subspecies, and islands. The genetic diversity was high. The mean number of allelesper locuswas 2.19, 67.6% of the loci were polymorphic and the mean heterozygosity was 0.268. The average total diversity was also high, FIT=0.547. Among population diversity, FST=0.459 contributed much more to the total diversity than within population diversity, FIS=0.163. My data thus seem to support the importance of the population as a main unit in evolution.

ISSN:0017-0070    

DOI:10.1080/11263509509436109

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0017-0070    

DOI:10.1080/11263509509436110

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0017-0070    

DOI:10.1080/11263509509436111

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor