Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Genetica ; 132(2): 143-58, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17549584

RESUMO

One of the major concerns of conservation biology is the knowledge on biodiversity. Many taxa have not yet been described and plant taxonomists are working hard to change this situation. This work presents a taxonomic overview of Solanum section Torva, from South Brazil, which still poorly understood. The section includes species known as "jurubeba" which are of considerable interest because of their pharmacological properties. Despite their higher economic value, it is difficult to identify the "jurubebas" correctly due to their taxonomic problems. A few questions on evolution concerning phylogenetic relationships in this section and other related sections of subgenus Leptostemonum were investigated to clarify the species circumscription and taxonomic issues. Eighty samples were analysed based on sequence variability of the internal transcribed spacers (ITS) of the nuclear ribosomal DNA, as well as the chloroplast intron trnL, trnL-trnF and trnS-trnG spacers. Five different matrixes were analyzed as the basis for a phylogenetic approach. The combined data from the chloroplast analyses formed well-supported trees. Solanum section Torva was proposed as a monophyletic group and it is close to S. melongena, S. jamaicense and S. sisymbriifolium.


Assuntos
Filogenia , Solanum/classificação , Solanum/genética , Sequência de Bases , Biodiversidade , Brasil , Núcleo Celular/genética , Sequência Consenso/genética , DNA de Cloroplastos/genética , DNA Espaçador Ribossômico/genética , Bases de Dados de Ácidos Nucleicos , Íntrons/genética , Análise de Sequência de DNA , Solanum/citologia
2.
Genetica ; 126(1-2): 15-32, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16502082

RESUMO

The present work intends to clarify the phylogenetic relationships among the species of Paspalum L. belonging to the informal groups Notata/Linearia and Dilatata, and to raise some preliminary hypotheses on the phylogeny of the genus as a whole. A combined dataset including morphological and molecular characters was used to analyze 28 species of Paspalum plus some representatives of related genera of the tribe Paniceae. Analyses were performed using both parsimony and maximum likelihood. The monophyly of Paspalum is not supported nor contradicted. The circumscription of informal groups of Paspalum is discussed, as well as the cladistic treatment of allopolyploid taxa, especially those comprising the Dilatata group. The relationships of members of the Dilatata with their putative progenitors is confirmed, but the monophyly of the group as a whole is not. A close relationship between P. dilatatum Poir. and P. lividum Trin. ex Schltdl. is shown. Our analysis is consistent with the monophyly of a group comprising Notata+Linearia, with a monophyletic Notata group nested within it. The delimitation of the core Notata is proposed by including P. conduplicatum Canto-Dorow, Valls and Longhi-Wagner, P. notatum Flüggé, P. minus E. Fourn., P. pumilum Nees and P. subciliatum Chase.


Assuntos
Paspalum/genética , Filogenia , Bases de Dados Genéticas , Análise de Sequência de DNA , Biologia de Sistemas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...