Estudos evolutivos no gênero pantropical Cissus L. (Vitaceae) com ênfase nas espécies neotropicais

• Ano de defesa: 2012
• Autor(a) principal: Jacqueline Gomes Rodrigues
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Genética; Cissus; Biogeografia
• Link de acesso: http://hdl.handle.net/1843/BUBD-98SHZF

Cissus L. is the largest genus of Vitaceae (the grape family) with about 350 species widely distributed in the tropical region. The genus Cissus displays extraordinary morphological diversity and complex geographical distribution with highest diversity is in South America and Africa. Previous molecular studies were conducted in the family Vitaceae, but many uncertainties remain in the group, mostly in infrageneric taxonomy ofCissus, with few species sampled, it was shown it is a polyphyletic group. The aim of this study, therefore, is to infer a phylogeny and biogeography for species of Cissus with focus in the new world species. The phylogenetic and divergence time were determined based ondata from three non-coding regions of chloroplast DNA (trnL intron, trnL-F intergenic region and the rps16 intron) and data from nuclear markers (ITS). The data of the marker trnL-F were combined with previous data published for family and were used for reconstruction area ancestor. All analyses showed that Cissus species do not form a monophyletic group,according the other molecular studies in the family. The species of South America Cissus striata, C. simsiana and C. tweediana are consistently grouped with the genus Australian Clematicissus. The four Australian species C. antarctica, C. hypoglauca, C. oblonga and C. sterculiifolia form a monophyletic group with the species C. trianae endemic to SouthAmerica. Through our analysis, we could not verify the relationship of this group with other species of Cissus. The other species of the genus form a monophyletic group which species of the new world form a single lineage. The monophyletic group of Cissus probably originated in Asia during the Eocene and could be an element of the forest boreotropical. The geographical relationship with the species of the Old World is complex with many disjunctions which may be a result of Laurasia migration. The clusters found in our molecular analysis combines several morphological groups proposed for South America species. Theleaf morphology provides phylogenetic signal and can be used as a character for infrageneric classification. The genus needs more studies aiming to eliminate the group polyphyly.