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High levels of genetic differentiation and selfing in the Brazilian cerrado fruit tree Dipteryx alata Vog. (Fabaceae)

TARAZI, Roberto; MORENO, Maria Andréia; GANDARA, Flávio Bertin; FERRAZ, Elza Martins; MORAES, Mário Luiz Teixeira; VINSON, Christina Cleo; CIAMPI, Ana Yamaguishi; VENCOVSKY, Roland; KAGEYAMA, Paulo Yoshio
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.12%
Dipteryx alata is a native fruit tree species of the cerrado (Brazilian savanna) that has great economic potential because of its multiple uses. Knowledge of how the genetic variability of this species is organized within and among populations would be useful for genetic conservation and breeding programs. We used nine simple sequence repeat (SSR) primers developed for Dipteryx odorata to evaluate the genetic structure of three populations of D. alata located in central Brazil based on a leaf sample analysis from 101 adults. The outcrossing rate was evaluated using 300 open-pollinated offspring from 25 seed-trees. Pollen dispersal was measured by parentage analysis. We used spatial genetic structure (SGS) to test the minimal distance for harvesting seeds in conservation and breeding programs. Our data indicate that the populations studied had a high degree of genetic diversity and population structure, as suggested by the high level of divergence among populations . The estimated outcrossing rate suggested a mixed mating system, and the intrapopulation fixation index was influenced by SGS. We conclude that seed harvesting for genetic conservation and breeding programs requires a minimum distance between trees of 196 m to avoid collecting seeds from related seed-trees.; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diversity and genetic structure in natural populations of Hancornia speciosa var. speciosa Gomes in northeastern Brazil; Diversidade e estrutura genética em populações naturais de Hancornia speciosa var. speciosa Gomes no nordeste do Brasil

Martins, Georgia Vilela; Martins, Luiza Suely Semen; Veasey, Elizabeth Ann; Lederman, Ildo Eliezer; Silva, Edson Ferreira da
Fonte: Sociedade Brasileira de Fruticultura Publicador: Sociedade Brasileira de Fruticultura
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.07%
Hancornia speciosa Gomes is a fruit tree native from Brazil that belongs to Apocinaceae family, and is popularly known as Mangabeira. Its fruits are widely consumed raw or processed as fruit jam, juices and ice creams, which have made it a target of intense exploitation. The extractive activities and intense human activity on the environment of natural occurrence of H. speciosa has caused genetic erosion in the species and little is known about the ecology or genetic structure of natural populations. The objective of this research was the evaluation of the genetic diversity and genetic structure of H. speciosa var. speciosa. The genetic variability was assessed using 11 allozyme loci with a sample of 164 individuals distributed in six natural populations located in the States of Pernambuco and Alagoas, Northeastern Brazil. The results showed a high level of genetic diversity within the species (e= 0.36) seeing that the most of the genetic variability of H. speciosa var. speciosa is within its natural populations with low difference among populations ( or = 0.081). The inbreeding values within ( = -0.555) and among populations ( =-0.428) were low showing lacking of endogamy and a surplus of heterozygotes. The estimated gene flow ( m ) was high...

Uso e diversidade genética em populações naturais de biriba (Eschweilera ovata [Cambess.] Miers): subsídios ao manejo e conservação da espécie.; Use and diversity genetic in natual populations of biriba (eschweilera ovata [cambess.] miers): subsidies to management and conservation of specie.

Gusson, Eduardo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/02/2004 PT
Relevância na Pesquisa
46.18%
A exploração de produtos não madeireiro em florestas nativas tem sido alternativa na composição da renda de comunidades locais. Dentre as diversas espécies exploradas da Mata Atlântica, a biriba - Eschweilera ovata (Cambess.) Miers - vem sendo intensamente utilizada para a confecção do berimbau. Disponibilizar informações que auxiliem em apontar diretrizes para adequadas formas de conservação genética e manejo desta espécie é de fundamental importância, tanto do ponto de vista ecológico como econômico e social. Com este objetivo, realizou-se o estudo do sistema reprodutivo e da estrutura ge nética de E. ovata, através da técnica de eletroforese de isoenzimas, em três áreas de ocorrência natural de populações da espécie sob diferentes graus de antropização, sendo uma explorada e outras duas sem exploração, localizadas próximas à cidade de Salvador - BA. Os resultados do sistema de reprodução, obtidos para duas populações, mostram que a espécie reproduz-se predominantemente por cruzamento, tendo $ t m variado de 98,5% a 99,9%, valor este superior à média apresentada pelas espécies arbóreas tropicais. Uma certa taxa de cruzamentos endogâmicos foi evidenciada nas populações estudadas...

Avaliação do estado de conservação de populações naturais de jatobá (Hymenaea courbaril L.) por meio de análises de estrutura genética e autocorrelação espacial; Assessment of the conservation status of natural populations of jatobá (Hymenaea courbaril L.) using a genetic structure and spatial autocorrelation approaches

Castellen, Milene da Silva
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/03/2006 PT
Relevância na Pesquisa
56.21%
Hymenaea courbaril (Caesalpinaceae) é uma espécie tropical madeireira que apresenta grande plasticidade fenotípica observada taxonomicamente na forma de seis variedades. Nove loci microssatélites foram utilizados para estudar a estrutura espacial e a distribuição da estrutura genética dentro e entre populações de Hymenaea courbaril var. stilbocarpa e Hymenaea courbaril var courbaril, no Brasil e no Panamá, respectivamente. Os níveis de diversidade genética obtidos nas cinco populações estudadas foram elevados, em média ∃ He = 0,744. Observou-se que a maior parte da variabilidade está contida dentro das populações e não entre as variedades estudadas. Desse modo, a diferenciação foi maior dentro de populações pertencentes a uma mesma região ( θ p / R =0,084) que entre regiões ( θ R =0,034). Adicionalmente, foram detectados significantes déficits de heterozigotos e elevados coeficientes de coancestria, associadas a um baixo tamanho efetivo em todas as populações estudadas. As análises moleculares indicaram diferenciação significativa, porém baixa, entre as variedades, tendo em vista a distância geográfica entre as mesmas e a plasticidade fenotípica observada. As análises de autocorrelação espacial revelaram a existência de uma forte estruturação entre os genótipos. Considerando o atual estágio de conservação da espécie e o grau de degradação na escala da paisagem...

Diversidade genética de populações de Cedro (Cedrela fissilis Vell. (Meliaceae)) no Centro-Sul do Brasil; Genetic diversity of populations of Cedro (Cedrela fissilis Vell. (Meliaceae)) in Southerncenter Brazil

Mendes, Flávio Bertin Gandara
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/10/2009 PT
Relevância na Pesquisa
46.07%
Cedrela fissilis Vell. é árvore alta (10 a 30 m) por 40 a 50 cm de diâmetro. Tronco retilíneo com sapopemas pouco desenvolvidas ou ausentes, mas quando atacado pela broca do ponteiro, Hypsipila grandela, é tortuoso. Casca grossa, dura, fissurada, de marrom a pardo - acinzentada. Folhas alternas com 8 a 24 pares de folíolos. Flores actinomorfas, unissexuadas, de 5 a 10 mm de comprimento reunidas em tirsos axilares. Os frutos são cápsulas lenhosas deiscentes de 3 a 10 cm de comprimento, que encerram de 30 a 300 sementes aladas, com até 35 mm de comprimento por 15 mm de largura. A polinização é realizada por insetos, possivelmente mariposas e abelhas e a dispersão de sementes é anemocórica. C. fissilis é uma das espécies arbóreas mais ameaçadas pelo corte seletivo e destruição da Mata Atlântica no centro-sul do Brasil, sua principal área de ocorrência, tornando a conservação dos seus recursos genéticos extremamente ameaçada pela redução populacional que vem sofrendo. Por outro lado, esta espécie tem um grande potencial para produção de madeira de alta qualidade, principalmente em plantios mistos, que estão se tornando economicamente viáveis pela escassez de madeira no mercado nacional e internacional...

Contemporary gene flow, mating system, and spatial genetic structure in a Jequitibá-rosa (Cariniana legalis Mart. Kuntze) fragmented population by microsatellite markers; Fluxo gênico contemporâneo, sistema de reprodução e estrutura espacial de genótipos em população fragmentada de jequitibá-rosa (Cariniana legalis Mart. O. Kuntze) utilizando marcadores microssatélites

Tambarussi, Evandro Vagner
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 17/02/2014 EN
Relevância na Pesquisa
46.15%
Cariniana legalis Mart. O. Kuntze (Lecidiaceae) is the largest tree of the Atlantic Forest. To contribute to in situ and ex situ genetic conservation programs for the species, herein we investigate the genetic diversity, inbreeding, intrapopulation spatial genetic structure (SGS), mating system and contemporary pollen flow in three fragmented populations of this species. We found 65 adult trees in the Ibicatu population, 22 in MGI, and four in MGII. Seeds were hierarchically sampled among and within fruits directly from the canopy of 15 seed-trees in Ibicatu (n= 40), five seed-trees in MGI (n= 50), and two seed-trees in MGII (n= 100). Thirteen specific microsatellite loci were developed and validated for 51 C. legalis trees. Eleven loci were polymorphic, revealing a maximum of two to 15 alleles per locus. Using the progeny arrays and seed-tree genotypes, we investigated the Mendelian inheritance, genetic linkage and genotypic disequilibrium of seven microsatellite loci specifically isolated for C. legalis and two previously developed heterologous microsatellite loci. No notable deviations from the expected Mendelian segregation, linkage, or genotypic disequilibrium were detected. The average allelic richness in the adult cohort of Ibicatu was 11.65 and 14.29 for MGI-II and for seeds it was 14.18 in Ibicatu and 10.85 in MGI-II; the average observed heterozygosity for adults of Ibicatu was 0.811 and 0.838 for MGI-II and for seeds it was 0.793 in Ibicatu and 0.786 in MGI-II; the average expected heterozygosity for adults of Ibicatu was 0.860 and 0.900 for MGI-II and for seeds it was 0.856 in Ibicatu and 0.853 in MGI-II. The average fixation index was significantly greater than zero for adults and seeds from both populations. Multilocus outcrossing rate ( m t ) in the three populations was significantly lower than unity (1.0)...

Genetic conservation of Brazilian fishes - Present state and perspectives

Wasko, Adriane P.; Martins, Cesar; Oliveira, Claudio; Forest, Fausto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 79-90
ENG
Relevância na Pesquisa
56.18%
Natural environments have been worldwide affected by the growing impact of anthropogenic actions that promote the reduction or the extinction of several vertebrate species. Aquatic ecosystems represent one of the most affected environments and many fish species and/or populations have been increasingly fragmented distributed due to habitat degradation, predatory fishing, introduction of exotic species, river sedimentation, deforestation, pollution, reduction of food resource, and construction of hydroelectric dams. Actually, more than 150 Brazilian fish species, including freshwater, estuary and coastal species, can be considered threatened. Information on the diversity, conservation biology and population analysis on threatened species or populations, with several DNA markers, can be extremely useful for the success of fish species-recovery and maintenance programs. Although DNA analysis in Neotropical fish species are just beginning, they tend to increase with the widespread attention to the use of molecular approaches to minimize problems related to the risk of extinction. The accumulation of information on biology and pattern of genetic variation of fish species, associated with ecological and demographic data, and also education and respect to the nature...

Transferability and use of microsatellite markers for the genetic analysis of the germplasm of some Arachis section species of the genus Arachis

Bravo, Juliana Pereira; Hoshino, Andrea Akemi; Angelici, Carla Maria Lara C.D.; Lopes, Catalina Romero; Gimenes, Marcos Aparecido
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 516-524
ENG
Relevância na Pesquisa
46.06%
The Arachis section is the most important of the nine sections of the genus Arachis because it includes the cultivated peanut, Arachis hypogaea. The genetic improvement of A. hypogaea using wild relatives is at an early stage of development in spite of their potential as sources of genes, including those for disease and pests resistance, that are not found in the A. hypogaea primary gene pool. Section Arachis species germplasm has been collected and maintained in gene banks and its use and effective conservation depends on our knowledge of the genetic variability contained in this material. Microsatellites are routinely used for the analysis of genetic variability because they are highly polymorphic and codominant. The objective of this study was to evaluate the transferability of microsatellite primers and the assay of genetic variability between and within the germplasm of some species of the Arachis section. Fourteen microsatellite loci developed for three different species of Arachis were analyzed and 11 (78%) were found to be polymorphic. All loci had transferability to all the species analyzed. The polymorphic loci were very informative, with expected heterozygosity per locus ranging from 0.70 to 0.94. In general, the germplasm analyzed showed wide genetic variation. © 2006 Sociedade Brasileira de Genética.

Genetic structure in fragmented populations of Solanum lycocarpum A. St.-Hil. with distinct anthropogenic histories in a Cerrado region of Brazil

Moura, T. M.; Martins, K.; Sujii, P. S.; Sebbenn, A. M.; Chaves, L. J.
Fonte: Funpec-Editora; Ribeirao Preto Publicador: Funpec-Editora; Ribeirao Preto
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.08%
Solanum lycocarpum is a woody tree widely distributed in the Cerrado that reaches high population densities in disturbed environments. We examined the genetic diversity and population differentiation of six S. lycocarpum populations with different degrees of human disturbance in order to determine if they are negatively affected by anthropogenic activity. Three populations located in southern and three located in southeastern regions of Goias State, Central Brazil, were genotyped with five microsatellite markers. The population located in a protected area had higher number of alleles (26) than the remaining populations (19 to 21 alleles). It indicates that extensive and continuous areas of preserved native vegetation contribute positively to the conservation of genetic diversity, even with S. lycocarpum that easily adapts to disturbed environments. The three southeastern populations, although fragmented, had preserved native vegetation and were not significantly different from each other (theta p = 0.002). All other population pairs compared were significantly divergent (theta p varied from 0.03 to 0.11 between pairs, P < 0.05). We found three distinct sets of allele frequencies. The three southeastern populations shared similar gene pools...

Phytochemical and genetic diversity in Mentha species: assessment, valorization and conservation

Rodrigues, Leandra Sofia de Matos
Fonte: ISA Publicador: ISA
Tipo: Tese de Doutorado
Publicado em //2012 ENG
Relevância na Pesquisa
46.05%
Doutoramento em Engenharia Agronómica - Instituto Superior de Agronomia; Mentha cervina (L.) Opiz and Mentha pulegium L. are medicinal and aromatic plants traditionally used in Portugal for aromatic and seasoning purposes and in folk medicine, for treatment of gastric and respiratory problems. Light and scanning electron microscopy of both species indumentum revealed non-glandular and glandular trichomes, corresponding to the common arrangement in Lamiaceae. Gas Chromatography and Gas Chromatography–Mass Spectrometry of both species essential oils (EOs) showed no chemical polymorphism in populations with different provenances, in cultivated or in wild growing conditions and at different developmental stages. All populations EOs belonged to the pulegone chemotype. M. cervina EOs antibacterial activity was higher than the main components alone, supporting the hypothesis of a synergistic effect of their different components. The antibacterial activity was more effective against Escherichia coli and Acinetobacter baumanni, validating their traditional use. The low levels of genetic diversity and the high structuring of M. cervina populations, assessed with Inter-simple sequence repeats markers, were assumed to result from a combination of evolutionary history and its unique biological traits...

Diversity and genetic structure in natural populations of Hancornia speciosa var. speciosa Gomes in northeastern Brazil

Martins,Georgia Vilela; Martins,Luiza Suely Semen; Veasey,Elizabeth Ann; Lederman,Ildo Eliezer; Silva,Edson Ferreira da
Fonte: Sociedade Brasileira de Fruticultura Publicador: Sociedade Brasileira de Fruticultura
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
Relevância na Pesquisa
46.07%
Hancornia speciosa Gomes is a fruit tree native from Brazil that belongs to Apocinaceae family, and is popularly known as Mangabeira. Its fruits are widely consumed raw or processed as fruit jam, juices and ice creams, which have made it a target of intense exploitation. The extractive activities and intense human activity on the environment of natural occurrence of H. speciosa has caused genetic erosion in the species and little is known about the ecology or genetic structure of natural populations. The objective of this research was the evaluation of the genetic diversity and genetic structure of H. speciosa var. speciosa. The genetic variability was assessed using 11 allozyme loci with a sample of 164 individuals distributed in six natural populations located in the States of Pernambuco and Alagoas, Northeastern Brazil. The results showed a high level of genetic diversity within the species (e= 0.36) seeing that the most of the genetic variability of H. speciosa var. speciosa is within its natural populations with low difference among populations ( or = 0.081). The inbreeding values within ( = -0.555) and among populations ( =-0.428) were low showing lacking of endogamy and a surplus of heterozygotes. The estimated gene flow ( m ) was high...

Analysis by RAPD of the genetic structure of Astyanax altiparanae (Pisces, Characiformes) in reservoirs on the Paranapanema River, Brazil

Leuzzi,Maria Sueli Papa; Almeida,Fernanda Simões de; Orsi,Mário Luís; Sodré,Leda Maria Koelblinger
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2004 EN
Relevância na Pesquisa
46.15%
In this study, the RAPD technique was used to analyze the genetic structure of populations of the fish Astyanax altiparanae (Characidae, Tetragonopterinae) living in the lower, middle and upper Paranapanema River, Brazil. The aim was to assess this structure regarding fish handling and conservation programs. The genetic variability (P) was found to be 42.64%, 75% and 75% in the low, middle and upper reaches, respectively. The dendrogram of genetic similarity, obtained by comparative analysis of the sets of samples from the three sites, showed the formation of three clusters. All of the genetic parameters used indicate that the population in the lower Paranapanema is genetically different from those in the middle and upper sections. The theta P test shows that the low Paranapanema is highly differentiated from the middle (0.2813) and upper (0.2912) Paranapanema, while the differentiation between the last two is moderate (0.0895). The data obtained in the present work suggest that recolonization and conservation studies should not be focused on the species A. altiparanae as such, but on the conservation units, because they are the genetically differentiated populations.

High levels of genetic differentiation and selfing in the Brazilian cerrado fruit tree Dipteryx alata Vog. (Fabaceae)

Tarazi,Roberto; Moreno,Maria Andréia; Gandara,Flávio Bertin; Ferraz,Elza Martins; Moraes,Mário Luiz Teixeira; Vinson,Christina Cleo; Ciampi,Ana Yamaguishi; Vencovsky,Roland; Kageyama,Paulo Yoshio
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
Relevância na Pesquisa
46.12%
Dipteryx alata is a native fruit tree species of the cerrado (Brazilian savanna) that has great economic potential because of its multiple uses. Knowledge of how the genetic variability of this species is organized within and among populations would be useful for genetic conservation and breeding programs. We used nine simple sequence repeat (SSR) primers developed for Dipteryx odorata to evaluate the genetic structure of three populations of D. alata located in central Brazil based on a leaf sample analysis from 101 adults. The outcrossing rate was evaluated using 300 open-pollinated offspring from 25 seed-trees. Pollen dispersal was measured by parentage analysis. We used spatial genetic structure (SGS) to test the minimal distance for harvesting seeds in conservation and breeding programs. Our data indicate that the populations studied had a high degree of genetic diversity and population structure, as suggested by the high level of divergence among populations . The estimated outcrossing rate suggested a mixed mating system, and the intrapopulation fixation index was influenced by SGS. We conclude that seed harvesting for genetic conservation and breeding programs requires a minimum distance between trees of 196 m to avoid collecting seeds from related seed-trees.

Conservation implications of the mating system of the Pampa Hermosa landrace of peach palm analyzed with microsatellite markers

Picanço-Rodrigues,Doriane; Astolfi-Filho,Spartaco; Lemes,Maristerra R.; Gribel,Rogerio; Sebbenn,Alexandre M.; Clement,Charles R.
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
Relevância na Pesquisa
46.12%
Peach palm (Bactris gasipaes) is cultivated by many indigenous and traditional communities from Amazonia to Central America for its edible fruits, and is currently important for its heart-of-palm. The objective of this study was to investigate the mating system of peach palm, as this is important for conservation and breeding. Eight microsatellite loci were used to genotype 24 open-pollinated progenies from three populations of the Pampa Hermosa landrace maintained in a progeny trial for genetic improvement. Both the multi-locus outcrossing rates (0.95 to 0.99) and the progeny level multi-locus outcrossing rates (0.9 to 1.0) were high, indicating that peach palm is predominantly allogamous. The outcrossing rates among relatives were significantly different from zero (0.101 to 0.202), providing evidence for considerable biparental inbreeding within populations, probably due to farmers planting seeds of a small number of open-pollinated progenies in the same plot. The correlations of paternity estimates were low (0.051 to 0.112), suggesting a large number of pollen sources (9 to 20) participating in pollination of individual fruit bunches. Effective population size estimates suggest that current germplasm collections are insufficient for long-term ex situ conservation. As with most underutilized crops...

Genetic Conservation: Our Evolutionary Responsibility

Frankel, O. H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1974 EN
Relevância na Pesquisa
46.08%
The conservation of the crop varieties of traditional agriculture in the centers of genetic diversity is essential to provide genetic resources for plant improvement. These resources are acutely threatened by rapid agricultural development which is essential for the welfare of millions. Methodologies for genetic conservation have been worked out which are both effective and economical. Urgent action is needed to collect and preserve irreplaceable genetic resources.

Genetic conservation of potentially immunogenic proteins among Brazilian isolates of Babesia bovis.

RAMOS, C. A. N.; ARAUJO, F. R.; ALVES, L. C.; SOUZA, I. I. F. de; GUEDES JUNIOR, D. S.; SOARES, C. O.
Fonte: Veterinary Parasitology, v. 187, n. 3-4, p. 548-552, julho, 2012. Publicador: Veterinary Parasitology, v. 187, n. 3-4, p. 548-552, julho, 2012.
Tipo: Artigo em periódico indexado (ALICE)
PT_BR
Relevância na Pesquisa
66.13%
Bovine babesiosis caused by Babesia bovis remains an important constraint for the development of cattle industries worldwide. Effective control can be achieved by vaccination with live attenuated phenotypes of the parasite. However, these vaccines have a number of drawbacks, which justifies the search for better, safer vaccines. In recent years, a number of parasite proteins with immunogenic potential have been discovered. However, there is little information on the genetic conservation of these proteins among different parasite isolates, which hinders their assessment as immunogens. The aim of the present study was to evaluate the conservation of the genes ama-1, acs-1, rap-1, trap, p0 and msa2c among five Brazilian isolates of B. bovis. Through polymerase chain reaction, genetic sequencing and bioinformatics analysis of the genes, a high degree of conservation (98?100%) was found among Brazilian isolates of B. bovis and the T2Bo isolate. Thus, these genes are worth considering as viable candidates to be included in a recombinant cocktail vaccine for cattle babesiosis caused by B. bovis.; 2012

The endangered species Brycon orbignyanus: genetic analysis and definition of priority areas for conservation

Ashikaga, Fernando Yuldi; Orsi, Mario Luis; Oliveira, Claudio; Senhorini, Jose Augusto; Foresti, Fausto
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 1845-1855
ENG
Relevância na Pesquisa
46.17%
Currently, biodiversity is threatened by several factors often associated with human population growth and the extension of areas occupied by human activity. In particular, freshwater fish fauna is affected by overfishing, deforestation, water pollution, introduction of exotic species and habitat fragmentation promoted by hydroelectric dams, among other environmental impact factors. Several action plans to preserve ichthyofauna biodiversity have been adopted; however, these plans frequently cover only a small number of species, and decisions are often made without strong scientific support. This study aimed to evaluate the genetic aspects of wild groups of Brycon orbignyanus, an endangered fish species, using microsatellites and D-loop regions to identify the genetic structure of the samples and to establish priority areas for conservation based on the genetic patterns of this species. The results indicated that the samples showed levels of genetic variability compatible with others studies with Neotropical fishes. However, the results obtained in the analysis of molecular variance (AMOVA) for microsatellites (F (ST) = 0.258) and D-loop (F (ST) = 0.234) and the interpopulation fixation index revealed that B. orbignyanus was structured in different subpopulations in the La Plata River basin; the areas with better environmental conditions also showed subgroups with higher rates of genetic variability. Future conservation actions addressing these sites should consider two different management units: the complex formed by the Ivinhema River...

Diversity and genetic structure in natural populations of Geonoma schottiana Mart (arecaceae): implications for conservation

Silva,Mirian de Sousa; Vieira,Fábio de Almeida; Carvalho,Dulcinéia de
Fonte: UFLA - Universidade Federal de Lavras Publicador: UFLA - Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 EN
Relevância na Pesquisa
56.16%
Geonoma schottiana is an underbrush palm which is found in high densities in tropical forests. This species is known for having an asynchronous fruit producing pattern, over all seasons of the year, thus being an important food source for frugivores. This work aims to determine the diversity and spatial genetic structure of two natural populations, referred to as MC I and MC II, of which 60 individuals were sampled, in Poço Bonito Biological Reserve, Lavras, Minas Gerais state. Results of 10 polymorphic isozyme loci indicated a high genetic diversity for the species (Ĥe= 0.428 and Ĥo = 0.570), with an mean number of alleles per locus of 2.0. Estimates of Cockerham's coancestry coefficients indicated an absence of intrapopulation ( or = -0.343) and interpopulation inbreeding ( or = -0.161), suggesting that on average populations are not endogamous. A high genetic divergence was found between populations ( = 13.5%), in comparison to most tropical species (<5%). Consequently...

Using pedigree analysis to monitor the local Piau pig breed conservation program

Veroneze,R.; Lopes,P.S.; Guimarães,S.E.F.; Guimarães,J.D.; Costa,E.V.; Faria,V.R.; Costa,K.A.
Fonte: Archivos de Zootecnia Publicador: Archivos de Zootecnia
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/03/2014 ENG
Relevância na Pesquisa
46.13%
The local Brazilian pig breed Piau is a lard-type pig that has undergone a breeding and selection process devised by the veterinarian Antonio Teixeira Vianna in 1939. The objective of the program was to develop a dual purpose animal, that is an animal suitable for the production of both fat and meat. The main characteristics of the Piau breed are rusticity, adaptability and high disease resistance. The conservation status of the breed is threatened, and in 1998, the Pig Breeding Farm at Universidade Federal de Viçosa (UFV, Viçosa, MG, Brazil) started a Piau herd for the purposes of conservation and use in genetic studies. The objectives of the present study were to describe the Piau genetic conservation program of the Universidade Federal de Viçosa (UFV) and to evaluate a range of population parameters to generate information for monitoring and improving the program. Population genetic structure analysis was performed using a pedigree file of 1349 animals and ENDOG v 4.8 software. The Piau conservation program has data and a collection of pedigree registers going back to the introduction of the first animals to the Pig Breeding Farm. The program used mating control, which is based on the mating of animals with the lowest pedigree-based relationships and on the maintenance of all the population's founding families. The effective numbers of founders and ancestors in the studied Piau population are 9 and 8 animals...

Genetic diversity and population structure of locally adapted South African chicken lines: implications for conservation

van Marle-Köster,E.; Hefer,C.A.; Nel,L.H.; Groenen,M.A.M.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2008 EN
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In this study microsatellite markers were applied to investigate the genetic diversity and population structure of the six local chicken lines kept in the "Fowls for Africa" program, for better clarification of parameters for breed differentiation and genetic conservation of this valuable resource. The lines included the Black Australorp, Potchefstroom Koekoek, New Hampshire, Ovambo, Lebova- Venda and a Naked Neck line. Unbiased estimates for heterozygosity ranged from 50% in the Potchefstroom Koekoek to as high as 65% in the Naked Neck chickens. F IS values varied from as low as 0.16 for the Black Australorp line to as high as 0.35 for the Ovambo chickens. The FST values indicated moderate to high genetic differentiation between the Naked Neck and New Hampshire (0.11); Ovambo and Naked Neck lines (0.12), and Naked Neck and Lebowa- Venda (0.14). A total of 13% of the total genetic variation observed was between the chicken lines and 87% within the lines, supporting moderate genetic differentiation. Population structure was assessed using STRUCTURE where the Black Australorp was genetically best defined. Although six clusters for the different populations could be distinguished, the other lines were not as clearly defined, with individual birds tending to share more than one cluster. Results support a broad classification of these lines and further investigation of unique alleles is recommended for conservation of the lines within the program.