Variações morfológicas, moleculares e fitoquímicas do Complexo geonoma maxima (poit.) Kunth (arecaceae) na Amazônia: elucidação de um problema taxonômico
Genus Geonoma known by its little taxonomically resolved representatives constitutes a favourable group for an integrated study on different segments. In order to do that, morphological, chemical, and molecular characters of four Geonoma species, known to constitute a species complex, were analys...
| Autor principal: | Souza, Maria Cristina de |
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| Grau: | Tese |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
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| Assuntos: | |
| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/12828 http://lattes.cnpq.br/6084626926551910 |
| Resumo: |
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Genus Geonoma known by its little taxonomically resolved representatives
constitutes a favourable group for an integrated study on different segments. In order
to do that, morphological, chemical, and molecular characters of four Geonoma
species, known to constitute a species complex, were analysed for the intent of a
taxonomical understanding. The study of the morphological characters points out four
distinct species: Geonoma maxima, Geonoma chelidonura, Geonoma spixiana and
Geonoma ambigua, based mainly on the variations presented by leaves and
inflorescences. Geonoma maxima presents pinnate linear-lanceolate leaves; two or
three times branched inflorescences and pits distributed far apart in spiral. Geonoma
ambigua presents forked leaves; just one-branched inflorescence, long rachillae and
pits close to one another in spiral. Geonoma chelidonura presents leaves with four to
five oblong-speared fellies; thin rachillae, branched twice and pits far apart in spiral.
Geonoma spixiana presents whole, forked and stongly plicate leaves; one-branched
inflorescence, bifid or trifid, thick and erect rachillae, with pits deeper and distributed
in well-defined series or rows. The study of the DNA through AFLP markers, revealed
two groups, one of them constituted by Geonoma maxima and Geonoma
chelidonura, and the other by Geonoma spixiana. Flavonoidic profile multivariate
analysis showed Geonoma maxima with just 15% of proximity in relation to Geonoma
chelidonura and Geonoma spixiana, while these two present higher proximity, 42%.
Cytogenetic analysis allows to point out superficially that Geonoma chelidonura
presents chromosome number between 26 and 28 (2n=26 or 28). No information
concerning this matter was obtained for the remaining species. It is concluded there
is some exchange of genes between Geonoma maxima and Geonoma chelidonura,
even with different phenotypes in their totality, and that Geonoma ambigua and
Geonoma spixiana are separate taxa. |