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1.
An Acad Bras Cienc ; 93(3): e20200297, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34406285

RESUMO

The tropical Andes constitute a natural barrier between the Pacific Ocean and the Atlantic; in these mountains, are a great variety of Ecosystems, defined by factors such as orography, winds, humidity, temperature, among others. Some of these Ecosystems have different environmental conditions from tropical ones. In them, there is a great Biodiversity, in some cases endemic and associated with relatively small geographic areas. An example of this biodiversity is the orchids of the genus Dracula, about which discussions are currently generated due to the difficulty in classifying their members. The present work shows a study where DNA was isolated and sequenced from plant samples obtained from 52 species of orchids of the genus Dracula, which were analyzed using the MEGA7 software. Phylogenetic analysis of the DNA sequences showed a well-resolved topology that reflects a geographical pattern of several major clades of the Pacific and Atlantic watersheds. Geophysical conditions of the Andes have generated greater biodiversity of the genus Dracula on the side of the Pacific. Although the species Dracula cordobae and alessandroi reported on both sides of the study site belong to the same clade and show limited mobility through the drier area to the South of the mountain range.


Assuntos
Ecossistema , Orchidaceae , Biodiversidade , Orchidaceae/genética , Filogenia , Filogeografia
2.
F1000Res ; 7: 209, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057750

RESUMO

Ecuador has a great variety of climatic regions that potentiate biodiversity. The family Orchidaceae constitutes one of the most important of the country, having identified about 4032 species with a high degree of endemism, therefore the development and research of alternative methods of storage and conservation of species is a strategy of primary interest for researchers and for society in general. In cryopreservation, temperatures reach below -190°C in order to paralyze the chemical reactions and keep the plant material viable for long periods. The present research focuses on the development of protocols for cryopreservation of seeds, aimed at the preservation of biodiversity, focusing on the family Orchidaceae, for the subsequent generation of a seed bank. The assays were performed on seeds of Epidendrum quitensium, Sobralia rosea, and Epidendrum anderssonii. Two freezing rates were tested: rapid freezing at -196°C; and step freezing at -22°C, -60°C to 196°C, further analyzed four combinations from Dimethylsulfoxide DMSO, glycerol and sucrose (DMSO 1M; DMSO 1M + glycerol 1M; DMSO 1M + sucrose 1M; DMSO 1M + glycerol 0,5M + sucrose 0,5M). The best results were obtained both in rapid and stepped freezing without the use of cryo-protective substances, by introducing the seeds directly into liquid nitrogen. Species of the genus Epidendrum presented a more efficient response in comparison to Sobralia. The viability of the seeds was evaluated by the tetrazolium test.

3.
Mol Biol Evol ; 35(2): 299-311, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29099937

RESUMO

Recent and compelling archaeological evidence attests to human presence ∼14.5 ka at multiple sites in South America and a very early exploitation of extreme high-altitude Andean environments. Considering that, according to genetic evidence, human entry into North America from Beringia most likely occurred ∼16 ka, these archeological findings would imply an extremely rapid spread along the double continent. To shed light on this issue from a genetic perspective, we first completely sequenced 217 novel modern mitogenomes of Native American ancestry from the northwestern area of South America (Ecuador and Peru); we then evaluated them phylogenetically together with other available mitogenomes (430 samples, both modern and ancient) from the same geographic area and, finally, with all closely related mitogenomes from the entire double continent. We detected a large number (N = 48) of novel subhaplogroups, often branching into further subclades, belonging to two classes: those that arose in South America early after its peopling and those that instead originated in North or Central America and reached South America with the first settlers. Coalescence age estimates for these subhaplogroups provide time boundaries indicating that early Paleo-Indians probably moved from North America to the area corresponding to modern Ecuador and Peru over the short time frame of ∼1.5 ka comprised between 16.0 and 14.6 ka.


Assuntos
Genoma Mitocondrial , Migração Humana , Indígenas Sul-Americanos/genética , Humanos , Filogenia , Filogeografia
4.
Biomed Res Int ; 2016: 9105746, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28074189

RESUMO

This work features the results of an ethnobotanical study on the uses of medicinal plants by the inhabitants of the region near to the Kutukú Scientific Station of Universidad Politécnica Salesiana, located in the Morona-Santiago province, southeast of Ecuador. In the surroundings of the station, one ethnic group, the Shuar, has been identified. The survey hereafter reports a total of 131 plant species, with 73 different therapeutic uses.


Assuntos
Medicina Tradicional/métodos , Fitoterapia/métodos , Plantas Medicinais/classificação , Equador , Feminino , Humanos , Masculino
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