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1.
Genetica ; 143(1): 21-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25532751

RESUMO

Podocarpus sellowii (Podocarpaceae) is one of only a few gymnosperms native to Brazil and the sole species of the genus found in the northeastern region of that country. It has a very restricted distribution in this region, with only three known populations in highland forests (called Brejos de Altitude), which apparently have been isolated from each other since the Pleistocene. Due to this long-term isolation and the fact that these populations have few adult individuals and suffer great anthropogenic pressure, low genetic variability is expected, compromising their long-term viability. The present work assessed the genetic variability and structure of northeastern populations of P. sellowii to investigate the role of Pleistocene glaciations on the genetic relationships between them and to propose strategies for their conservation by analyzing the SSR and ISSR markers of adult and juvenile individuals. Low genetic diversity was found with both markers, associated with a high differentiation of the Brejo de Baturité population in relation to the others-suggesting their isolation at different points in time, probably during the Pleistocene. Actions directed towards increasing the genetic diversity of these populations will be needed, such as planting seedlings with high genetic variability-but the high degrees of differentiation observed between the populations must be taken into account.


Assuntos
Florestas , Variação Genética , Genética Populacional , Traqueófitas/classificação , Traqueófitas/genética , Alelos , Evolução Molecular , Loci Gênicos , Geografia , Repetições de Microssatélites , Filogenia , Polimorfismo Genético
2.
Acta Trop ; 134: 80-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24631342

RESUMO

In recent years, high levels of Aedes aegypti infestation and several dengue outbreaks with fatal outcome cases have been reported in Manaus, State of Amazonas, Brazil. This situation made it important to understand the genetic structure and gene flow patterns among the populations of this vector in Manaus, vital pieces of information for their management and development of new control strategies. In this study, we used nine microsatellite loci to examine the effect of seasonality on the genetic structure and gene flow patterns in Ae. aegypti populations from four urban neighborhoods of Manaus, collected during the two main rainy and dry seasons. All loci were polymorphic in the eight samples from the two seasons, with a total of 41 alleles. The genetic structure analyses of the samples from the rainy season revealed genetic homogeneity and extensive gene flow, a result consistent with the abundance of breeding sites for this vector. However, the samples from the dry season were significantly structured, due to a reduction of Ne in two (Praça 14 de Janeiro and Cidade Nova) of the four samples analyzed, and this was the primary factor influencing structure during the dry season. Genetic bottleneck analyses suggested that the Ae. aegypti populations from Manaus are being maintained continuously throughout the year, with seasonal reduction rather than severe bottleneck or extinction, corroborating previous reports. These findings are of extremely great importance for designing new dengue control strategies in Manaus.


Assuntos
Aedes/classificação , Aedes/crescimento & desenvolvimento , Dengue/transmissão , Estruturas Genéticas , Variação Genética , Insetos Vetores , Aedes/genética , Animais , Brasil , Fluxo Gênico , Humanos , Repetições de Microssatélites , Estações do Ano , População Urbana
3.
Mol Ecol Resour ; 11(4): 757-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21627775

RESUMO

This article documents the addition of 111 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Acipenser oxyrinchus desotoi, Anopheles nuneztovari sensu lato, Asellus aquaticus, Calopteryx splendens, Calopteryx virgo, Centaurea aspera, Centaurea seridis, Chilina dombeyana, Proctoeces cf. lintoni and Pyrenophora teres f. teres.


Assuntos
Bases de Dados Genéticas , Repetições de Microssatélites , Acanthaceae/genética , Animais , Artrópodes/genética , Ascomicetos/genética , Cordados/genética , Dados de Sequência Molecular , Plantas/genética , Análise de Sequência de DNA , Trematódeos/genética
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