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1.
An Acad Bras Cienc ; 87(4): 2031-46, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26628033

RESUMEN

We submitted tree species occurrence and geoclimatic data from 59 sites in a river basin in the Atlantic Forest of southeastern Brazil to ordination, ANOVA, and cluster analyses with the goals of investigating the causes of phytogeographic patterns and determining whether the six recognized subregions represent distinct floristic units. We found that both climate and space were significantly (p ≤ 0.05) important in the explanation of phytogeographic patterns. Floristic variations follow thermal gradients linked to elevation in both coastal and inland subregions. A gradient of precipitation seasonality was found to be related to floristic variation up to 100 km inland from the ocean. The temperature of the warmest quarter and the precipitation during the coldest quarter were the main predictors. The subregions Sandy Coastal Plain, Coastal Lowland, Coastal Highland, and Central Depression were recognized as distinct floristic units. Significant differences were not found between the Inland Highland and the Espinhaço Range, indicating that these subregions should compose a single floristic unit encompassing all interior highlands. Because of their ecological peculiarities, the ferric outcrops within the Espinhaço Range may constitute a special unit. The floristic units proposed here will provide important information for wiser conservation planning in the Atlantic Forest hotspot.

2.
PLoS Biol ; 13(7): e1002204, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26204382

RESUMEN

Addressing the challenges of biodiversity conservation and sustainable development requires global cooperation, support structures, and new governance models to integrate diverse initiatives and achieve massive, open exchange of data, tools, and technology. The traditional paradigm of sharing scientific knowledge through publications is not sufficient to meet contemporary demands that require not only the results but also data, knowledge, and skills to analyze the data. E-infrastructures are key in facilitating access to data and providing the framework for collaboration. Here we discuss the importance of e-infrastructures of public interest and the lack of long-term funding policies. We present the example of Brazil's speciesLink network, an e-infrastructure that provides free and open access to biodiversity primary data and associated tools. SpeciesLink currently integrates 382 datasets from 135 national institutions and 13 institutions from abroad, openly sharing ~7.4 million records, 94% of which are associated to voucher specimens. Just as important as the data is the network of data providers and users. In 2014, more than 95% of its users were from Brazil, demonstrating the importance of local e-infrastructures in enabling and promoting local use of biodiversity data and knowledge. From the outset, speciesLink has been sustained through project-based funding, normally public grants for 2-4-year periods. In between projects, there are short-term crises in trying to keep the system operational, a fact that has also been observed in global biodiversity portals, as well as in social and physical sciences platforms and even in computing services portals. In the last decade, the open access movement propelled the development of many web platforms for sharing data. Adequate policies unfortunately did not follow the same tempo, and now many initiatives may perish.


Asunto(s)
Biodiversidad , Bases de Datos como Asunto , Brasil , Bases de Datos como Asunto/economía
3.
PhytoKeys ; (38): 69-87, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25009438

RESUMEN

Three new Brazilian species of the Brevantherum clade of Solanum (Solanaceae) are described, all closely related to the poorly known Solanum inornatum Witasek. Solanum bradei Giacomin & Stehmann, sp. nov., and Solanum kriegeri Giacomin & Stehmann, sp. nov., differ from S. inornatum in having very small deltate calyx lobes that are not accrescent in fruit. Solanum bradei is a shrub up to 1.8 m with generally pedunculate inflorescences and tiny translucent fruits, whereas Solanum kriegeri is a dwarf glabrescent plant growing on sandy soils in cloud forests, with larger fruits and sessile to subsessile inflorescence. Solanum friburgense Giacomin & Stehmann, sp. nov., has linear calyx lobes like S. inornatum, and is characterized by its 2-foliate sympodia and leaf pubescence, with trichomes concentrated on leaf veins. The species here described and illustrated are restricted to the mountain ranges of Mantiqueira and Serra do Mar in the Atlantic forests of southeastern Brazil and are all of considerable conservation concern.


ResumoTrês novas espécies pertencentes ao clado Brevantherum do gênero Solanum (Solanaceae) são descritas, todas proximamente relacionadas a Solanum inornatum Witasek. Solanum bradei Giacomin & Stehmann, sp. nov., e Solanum kriegeri Giacomin & Stehmann, sp. nov., diferem de S. inornatum por apresentarem lobos do cálice deltoides, muito pequenos, não acrescentes no fruto, mas a primeira se destaca por apresentar um porte marcadamente maior, chegando a formar arbustos de até 1.8 m, com inflorescências geralmente pedunculadas e frutos diminutos translúcidos, enquanto Solanum kriegeri é uma forma anã e glabrescente que habita matas nebulares associadas a solos arenosos. Solanum friburgense Giacomin & Stehmann, sp. nov., apresenta lobos do cálice lineares, como em S. inornatum, mas se diferencia pelo simpódio 2-foliado e indumento das folhas, com tricomas concentrados nas nervuras. As espécies aqui descritas e ilustradas são restritas às Serras da Mantiqueira e do Mar no domínio Atlântico do sudeste brasileiro e são indicadas como ameaçadas de extinção.

4.
Mol Ecol ; 19(23): 5240-51, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21040052

RESUMEN

In the Southern and Southeastern Brazilian highlands, a clade of seven species of Petunia that are endemic to the region (P. altiplana, P. bonjardinensis, P. guarapuavensis, P. mantiqueirensis, P. reitzii, P. saxicola and P. scheideana) exists in association with grassland formations. These formations are isolated in high-altitude regions, being surrounded by forested areas, and experienced contraction-expansion cycles associated with the glacial cycles of the Pleistocene. To understand the evolutionary history of this group, the divergence of which is probably linked to these past shifts in habitat, we analysed the sequences of the plastidial intergenic spacers trnH-psbA and trnS-trnG from populations throughout the known distributions of all seven species. The common ancestor of this highland clade started to differentiate ∼0.9 million years (Myr) ago, which corresponds to a high diversification rate of 2.06 species per Myr in the intervening period. The high level of haplotype sharing among several species in the clade and the absence of reciprocal monophyly suggest the persistence of ancestral polymorphisms during speciation events and/or past hybridization, because no hybrid was found. Four of the five species displayed very low genetic diversity and possessed either one or two haplotypes, which is consistent with long-term isolation in restricted areas. The three more diverse species displayed significant population structure, and P. altiplana showed a clear signs of population growth during the last glacial period. These results suggest that diversification occurred as a result of expansion of the ancestral species of the clade during glacial periods followed by fragmentation and isolation during retraction in interglacial periods.


Asunto(s)
Evolución Molecular , Genética de Población , Petunia/genética , Filogeografía , Brasil , ADN de Cloroplastos/genética , ADN de Plantas/genética , ADN Espaciador Ribosómico/genética , Ecosistema , Variación Genética , Haplotipos , Filogenia , Análisis de Secuencia de ADN
5.
Mol Ecol ; 15(14): 4487-97, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17107478

RESUMEN

Intrinsic reproductive barriers among the species of Petunia are weak and genetic isolation is obtained mainly by geographical separation and ecological diversification. The Serra do Sudeste region in the extreme south of Brazil is one of the centres of diversity of this genus and is characterized by the presence of species with different pollination syndromes. Petunia exserta is known only from four sandstone towers in a restricted area of this region (about 500 km(2)) and is characterized by its differentiated habitat (shelters in the sandstone towers) and by its floral characteristics adapted to ornithophily. In towers where this species is sympatric with the sphingophilous Petunia axillaris, phylogenetically close to P. exserta, we found plants with intermediate floral morphology, suggesting hybridization between them. To test this hypothesis and to better understand its consequences we analysed the sequences of the plastid trnH-psbA, trnS-trnG and psbB-psbH intergenic spacers in 121 individuals sampled all over the P. exserta distribution. The joint analysis of the three markers revealed 13 haplotypes and the network showed two main genetic clades, which probably represent the original gene pool of the two species in the region. In general, individuals of a given population presented the same haplotype, independently of phenotype, corroborating the hybridization hypothesis. Field observations suggest that hummingbirds are responsible for the interspecific gene flow. Analysis of molecular variance revealed high interpopulational diversity among the towers. The low gene flow between populations is possibly related to the autochoric seed dispersion system.


Asunto(s)
Ecología , Variación Genética , Hibridación Genética , Petunia/genética , Geografía , Haplotipos/genética , Dinámica Poblacional
6.
Genetica ; 126(1-2): 3-14, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16502081

RESUMEN

Representatives from 11 Petunia Jussieu species in south and southeast Brazil were compared with two Calibrachoa La Llave & Lex., one Bouchetia Dunal, and two Nierembergia Ruiz & Pav. taxa in relation to DNA molecular variability. A total of 4532 base pairs related to one nuclear, five plastidial and one mitochondrial systems was investigated. Petunia and Calibrachoa, although separated among themselves, clearly differentiate from the two other genera. Despite the fact that the Petunia species do not show marked molecular differences, they can be separated in two complexes, in good agreement with altitude data. Petunia + Calibrachoa should have diverged from other clades at about 25 million years before present.


Asunto(s)
Evolución Molecular , Genoma de Planta , Petunia/genética , Filogenia , Marcadores Genéticos
7.
Cad. farm ; 1(2): 65-72, 1985.
Artículo en Portugués | LILACS | ID: lil-31761

RESUMEN

Os medicamentos sintéticos ou os produtos naturais isolados substituíram neste século as plantas medicinais e suas formas derivadas na terapéutica. Atualmente, tais recursos passaram a ser cogitado, por profissionais de saúde e órgäos governamentais, como uma forma de ampliar o atendimento das necessidades dos serviços de saúde. Os limites e as dificuldades da incorporaçäo desses recursos na medicina científica säo discutidos


Asunto(s)
Plantas Medicinales , Medicina Tradicional
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