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Establishing a soybean germplasm core collection

OLIVEIRA, Marcelo F.; NELSON, Randall L.; GERALDI, Isaias O.; CRUZ, Cosme D.; TOLEDO, Jose Francisco F. de
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
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Core collections are of strategic importance as they allow the use of a small part of a germplasm collection that is representative of the total collection. The objective of this study was to develop a soybean core collection of the USDA Soybean Germplasm Collection by comparing the results of random, proportional, logarithmic, multivariate proportional and multivariate logarithmic sampling strategies. All but the random sampling strategy used stratification of the entire collection based on passport data and maturity group classification. The multivariate proportional and multivariate logarithmic strategies made further use of qualitative and quantitative trait data to select diverse accessions within each stratum. The 18 quantitative trait data distribution parameters were calculated for each core and for the entire collection for pairwise comparison to validate the sampling strategies. All strategies were adequate for assembling a core collection. The random core collection best represented the entire collection in statistical terms. Proportional and logarithmic strategies did not maximize statistical representation but were better in selecting maximum variability. Multivariate proportional and multivariate logarithmic strategies produced the best core collections as measured by maximum variability conservation. The soybean core collection was established using the multivariate proportional selection strategy. (C) 2010 Elsevier B.V. All rights reserved.

Molecular and morphological diversity in Japanese rice germplasm

BOSETTI, Fatima; ZUCCHI, Maria Imaculada; PINHEIRO, Jose Baldin
Fonte: CAMBRIDGE UNIV PRESS Publicador: CAMBRIDGE UNIV PRESS
Tipo: Artigo de Revista Científica
ENG
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Germplasm molecular and phenotypic characterization is instrumental to its utilization and to genetic variability incorporation into rice breeding programmes. The diversity within 192 Japanese rice accessions was analysed for 22 agro-morphological traits and 24 single sequence repeat markers. A total of 181 alleles were detected, 38 of which were exclusive. The number of alleles/marker ranged from 2 to 16, with an average of 7.54 alleles/locus and the H(e) value ranged from 0.01 to 0.82, with an average of 0.46. The accessions showed diversity at molecular and phenotypic level and few showed also good agronomic performance. Tocher`s method applied on a total-dissimilarity matrix was used to determine cluster formation of 13 diversity groups. Most of the accessions (81%) were clustered within a group, whereas eight accessions (Kyuushuu, Eika Ine, Ishiwari Mochi, Col/Fukui/1965, Ookuma Nishiki, Suzume Shirazu, Iwate Ryoon and Toga) did not cluster with other accessions.

Microsatellite diversity and effective population size in a germplasm bank of Hymenaea courbaril var. stilbocarpa (Leguminosae), an endangered tropical tree: recommendations for conservation

FERES, Juliana Massimino; GUIDUGLI, Marcela Corbo; MESTRINER, Moacyr Antonio; SEBBENN, Alexandre Magno; CIAMPI, Ana Yamaguishi; ALZATE-MARIN, Ana Lilia
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
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Deforestation in southeast Brazil has led to the extinction of Hymenaea courbaril var. stilbocarpa and ex situ conservation has been established. In this study, the levels of genetic diversity and the effective population size of H. courbaril in a germplasm bank were investigated using six nuclear microsatellite loci. A total of 79 and 91 alleles were found in 65 seed-trees and their 176 offspring, respectively. Offspring have a higher average number of alleles per locus (A = 15.2) than seed-trees (A = 13.2), but lower observed heterozygosity (offspring: H (o) = 0.566; seed-trees: H (o) = 0.607). The estimate of outcrossing rate shows that the study population is perfectly outcrossed (t (m) = 0.978, P > 0.05). Significant deviations from random mating were detected through mating among relatives and correlated matings. The average variance in effective population size for each family was 2.63, with a total effective population size retained in the bank of 170.1. These results confirm that the preserved population of H. courbaril retains substantial genetic variability.; FAPESP[03/04199-4]; Sao Paulo University (USP); FAEPA; CAPES

Caracterização e ocorrência de agentes causais de oídio em cucurbitáceas no Brasil e reação de germoplasma de meloeiro; Characterization and occurrence of causal agents of powdery mildew in cucurbits in Brazil and reaction of melon germplasm

Fazza, Ana Carolina
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 29/06/2006 PT
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O meloeiro é uma cultura de relevância econômica no Brasil, principalmente na região Nordeste, onde grande parte da produção é exportada. Entre os fatores limitantes da cultura está o oídio, que pode ser controlado através do uso de variedades resistentes. No entanto, para que isto seja possível, é necessário que se tenha conhecimento sobre qual é o agente causal em ocorrência na região de produção e quais são as fontes de inóculo desta doença. O presente trabalho teve como objetivos o levantamento das espécies e raças de oídio com ênfase na região Nordeste, a verificação da patogenicidade de isolados provenientes de outras cucurbitáceas em relação ao meloeiro, a avaliação de germoplasma de meloeiro para resistência a P. xanthii raça 2 (francesa), a proposição de um sistema de cultivares de meloeiro para caracterização de raças de P. xanthii e a otimização de um protocolo de extração de DNA de P. xanthii. No total de 65 isolados analisados, observou-se que Podosphaera xanthii foi a única espécie encontrada entre as amostras. Dentre estas, as raças 1 e 2 foram as prevalentes. Também foram observadas as raças 0, 3, 4 e 5 em menor freqüência. As culturas de abóbora, abobrinha, melancia e pepino apresentaram-se como fontes de inóculo de oídio para o meloeiro...

Diversidade genética em germoplasma de soja identificada por marcadores SSR, EST-SSR e caracteres agromorfológicos; Genetic diversity in soybean germplasm identified by SSR and EST-SSR markers and agromorphological traits

Mulato, Bruno Mello
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 30/11/2009 PT
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Diversos estudos afirmam ser bastante restrita a base genética da soja cultivada, o que gera problemas como falta de variabilidade, fragilidade das cultivares e alcance de um limite de produtividade. O desafio é selecionar dentre o germoplasma quais acessos utilizar em um programa de melhoramento. Este trabalho objetivou analisar a diversidade genética de 79 acessos de soja de diferentes regiões do mundo. Para tanto, foram utilizados marcadores microssatélites genômicos, funcionais e caracteres agromorfológicos. Vinte caracteres agromorfológicos foram avaliados em campo e submetidos a análises multivariadas para a estimação da diversidade genética. A dissimilaridade genética entre os acessos foi calculada pela distância generalizada de Mahalanobis, utilizando-se, a seguir, o algoritmo de otimização de Tocher para o agrupamento dos acessos. A análise de agrupamento resultou em 16 grupos, com cinco deles contendo um só acesso. PIs de mesma origem geográfica foram alocadas no mesmo grupo, com exceções. A primeira variável canônica absorveu 76,99% da variação observada, sendo as características com maior contribuição número de dias para a maturidade e início da granação. A segunda variável canônica absorveu 13...

Desenvolvimento de marcadores microssatélites e caracterização do germoplasma de mamona (Ricinus communis L.); Development and characterization of microsatellite markers for castor (Ricinus communis L.) germplasm

Bajay, Miklos Maximiliano
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 28/01/2010 PT
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A mamona (Ricinus communis) é uma cultura de clima tropical de importância social e econômica no Brasil e no mundo. As sementes contém um óleo com excelentes propriedades para o uso industrial. Esse óleo é o mais indicado para a produção de biodiesel, pois é o único solúvel em álcool e requer menos calor que os outros óleos vegetais para a produção de combustível. A grande diversidade genética observada no germoplasma de mamoneira possibilita a seleção de genótipos superiores a partir do material base, no entanto não existem informações sobre a caracterização molecular desses acessos, representando um sério risco quanto a perda de diversidade genética. O sucesso dos programas de melhoramento depende do conhecimento sobre a diversidade genética do banco ativo de germoplasma. Os microssatélites são ferramentas moleculares muito úteis em estudos de diversidade. Desta forma uma biblioteca genômica foi construída para a seleção dos fragmentos contendo marcadores moleculares microssatélites (SSR), a serem utilizados para estimar a diversidade genética dos acessos do banco de germoplasma da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), do Instituto Agronômico de Campinas (IAC) e da UNESP - Botucatu. A partir dos 41 locos analisados...

Caracterização molecular de acessos de bananeira do banco de germoplasma da Embrapa; Molecular characterization of banana accessions from the Embrapa germplasm collection

Jesus, Onildo Nunes de
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 16/04/2010 PT
Relevância na Pesquisa
36.87%
Os marcadores microssatélites por serem de natureza codominante e multialélica tornam-se ideais para a caracterização, mapeamento e seleção assistida. Os locos microssatélites disponíveis têm sido utilizados efetivamente na caracterização de acessos de bananeira (Musa), porém muitos deles têm se mostrado com baixa eficiência de amplificação. Neste sentido, os objetivos deste trabalho foram: desenvolver novos locos de microssatélites, caracterizar 224 acessos de bananeira do banco de germoplasma da Embrapa em relação à ploidia e constituição genômica empregando abordagens moleculares e estabelecer relações genéticas entre eles. Foram desenvolvidos 50 novos locos de microssatélites dos quais 44 foram polimórficos entre os acessos analisados. Para a caracterização da ploidia dos acessos foi utilizado a citometria de fluxo, e para a definição da composição genômica foram empregados polimorfismo nos genes ribossomiais nucleares (rDNA) e 16 locos microssatélites, que também serviram para estabelecer as relações genéticas entre os acessos. Além disso, foram sequenciados regiões do rDNA de 17 acessos de bananeira para identificação de polimorfismo de base única (SNP) associados ao genoma A e B. A constituição genômica e/ou ploidia determinada por abordagens moleculares confirmou a classificação previamente estabelecida por descritores morfológicos...

Diversidade genética em germoplasma de arroz filipino identificada por marcadores moleculares e caracteres agromorfológicos; Genetic diversity in philippine rice germplasm identified by molecular markers and agromorphological traits

Mata, Thiago Luiz da
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 13/07/2010 PT
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A utilização intensiva de germoplasma melhorado de arroz reduziu a variabilidade genética necessária no processo de seleção causando a estagnação dos níveis de produtividade. Visando aumentar a base genética das variedades comerciais ocorre uma busca por genes nos BAG´s. Para este fim, a avaliação de 144 acessos de arroz filipino provenientes do banco da ESALQ/USP foi realizada através de dezenove caracteres agromorfológicos e 15 marcadores microssatélite. As análises de agrupamento com base nos dados moleculares discriminaram um total de 3 grupos. Todos os 15 locos analisados na genotipagem dos acessos foram polimórficos, sendo encontrados 156 alelos. O número de alelos por loco variou de 3 a 20, com uma média de 10,4. Os acessos analisados possuem uma quantidade bastante significativa de alelos raros (70), sendo os genótipos 84 (Mum 1), 106 (Khao Phe Do), 68 (Khao Khane), 132 (Ku-79-1), 112 (E-Boot), 64 (Bikyat), 146 (BRS-Sertaneja), 121 (Puntas Claras), 85 (Khao Phe Py), 138 (Maraja), 133 (Unnamed), 105 (Os-6), 107 (Ba Ke Gonh) e 47 (Khao Mack Fay Khao) os que apresentaram alelos exclusivos. A heterozigosidade esperada teve seu maior valor no loco RM 257 (0,934) e seu menor valor no loco RM 277 (0,542). Os caracteres agromorfológicos foram submetidos a análises univariadas e multivariadas para a estimação da diversidade genética. Com base no teste F...

Diversidade genética e química em germoplasma de gengibre (Zingiber officinale); Chemical and genetic diversity of ginger germplasm (Zingiber officinale)

Blanco, Eleonora Zambrano
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 07/04/2015 PT
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Os recursos genéticos vegetais apresentam um valor real e potencial para a agricultura em razão da sua importância em programas de melhoramento e conservação. Este estudo teve como objetivo principal caracterizar a diversidade genética e química do germoplasma de gengibre do Departamento de Genética da ESALQ/USP, por meio de 18 descritores fenotípicos, 13 combinações de marcadores AFLP e análise da composição química do óleo essencial. O germoplasma foi formado por acessos procedentes de distintos estados brasileiros, além de algúns acessos introduzidos da Colômbia. Durante as coletas, foram entrevistados 34 agricultores de três estados: São Paulo (SP), Espírito Santo (ES) e Paraná (PR), constatando-se que esta espécie é cultivada principalmente por agricultores familiares cuja fonte principal de renda é a agricultura. Na análise da composição química, um total de 61 compostos foram identificados, sendo que os acessos apresentaram variabilidade química segundo a análise de variância. O óleo essencial foi rico em monoterpenos (82,35%), destacando-se geranial (20,41%) e neral (13,36%) como os compostos mais abundantes. Os compostos α-zingibereno, 1,8-cineol, linalol e β-felandreno, foram importantes na análise da diversidade química e...

Antioxidant content in guava (Psidium guajava) and araca (Psidium spp.) germplasm from different Brazilian regions

Correa, Luiz Claudio; Santos, Carlos Antonio F.; Vianello, Fabio; Lima, Giuseppina Pace Pereira
Fonte: Cambridge University Press Publicador: Cambridge University Press
Tipo: Artigo de Revista Científica Formato: 384-391
ENG
Relevância na Pesquisa
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Guava (Psidium guajava) and araca (Psidium spp.) plants are important for the Brazilian economy, as their fruit is both accepted by the consumers, and makes a beneficial contribution to the human diet thanks to their content in vitamin C, carotenoids and phenolic compounds. Here, we report the content in the fruit of free ascorbic acid, lycopene, beta-carotene, flavonoids and phenolic compounds, and the total antioxidant activity present in a collection of guava and araca accessions curated at the Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Semiarido germplasm bank. Guava fruits with a red-coloured pulp flesh contained a significant amount of carotenoids, especially lycopene, and a high concentration of phenolic compounds. These compounds were largely responsible for the antioxidant activity of the araca accessions. Among the guava accessions, phenolic compounds were also responsible for the antioxidant activity. High levels of free ascorbic acid were present in most accessions. In both guava and araca, there is substantial potential to develop cultivars with a good level of consumer acceptability.

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
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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.

Collection of Lupinus angustifolius L. germplasm and characterisation of morphological and molecular diversity

Talhinhas, Pedro; Leitão, José; Martins, João Neves
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em //2006 ENG
Relevância na Pesquisa
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Lupinus angustifolius L. is a Mediterranean species, domesticated in the 20th century, representing an important grain legume crop in Australia and other countries. This work is focused on the collection of wild germplasm and on the characterisation of morphological and molecular diversity of germplasm accessions. It reports the collection of 81 wild L. angustifolius accessions from the South and Centre of Portugal, available at the ‘Instituto Superior de Agronomia Gene Bank’, with subsequent morphological and molecular characterisation of a selection of these and other accessions. A multivariate analysis of morphological traits on 88 L. angustifolius accessions (including 59 wild Portuguese accessions, 15 cultivars and 14 breeding lines) showed a cline of variation on wild germplasm, with plants from Southern Portugal characterised by earlier flowering, higher vegetative development and larger seeds. AFLP and ISSR molecular markers grouped modern cultivars as sub-clusters within the wider diversity of wild germplasm, revealing the narrow pool of genetic diversity on which domesticated accessions are based. The importance of preserving, characterising and using wild genetic resources for L. angustifolius crop improvement is outlined by the results obtained.

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: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 EN
Relevância na Pesquisa
37.11%
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.

Incorporating different proportions of exotic maize germplasm into two adapted populations.

SANTOS, M.X. dos; POLLAK, L.M.; PACHECO, C.A.P.; GUIMARAES, P.E.O.; PETERNELLI, L.A.; PARENTONI, S.N.; NASS, L.L.
Fonte: Genetics and Molecular Biology, Ribeirão Preto, v. 23, n. 2, p. 445-451, 2000. Publicador: Genetics and Molecular Biology, Ribeirão Preto, v. 23, n. 2, p. 445-451, 2000.
Tipo: Artigo em periódico indexado (ALICE)
EN
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Maize breeders frequently wish to use exotic germplasm in their breeding programs without losing specific characteristics of their adapted material. The objective of this study was to determine the optimal proportions of exotic germplasm to incorporate into adapted populations (F2 = 50% exotic, BC1 = 25% exotic, BC2 = 12.5% exotic and BC3 = 6.25% exotic) to form the initial foundation population and to determine the heterosis between adapted x exotics. We used six exotic populations of different origins and two adapted populations representing a Brazilian heterotic pattern. In 1993-94 and 1994-95, the parents, F1, F2, BC1, BC2, BC3 and four checks were evaluated in six environments in central Brazil using an 8 x 9 simple rectangular lattice design. Higher mean values for yield were obtained as the proportions of exotic germplasm decreased. Some backcrosses produced more than the adapted populations BR 105 (7.59 ton/ha) and BR 106 (8.43 ton/ha). The best results were obtained when incorporating 6.25 or 12.5% of exotic genes. This trend was true for root lodging, stalk lodging and ear diseases but not for plant and ear height. The midparent heterosis for yield varied from - 16.1 to 40.3%. Midparent heterosis with positive and negative values were also found for the other traits. The results indicate the potential of exotic germplasm for developing good hybrids. After choosing the best exotic source...

Characterisation of germplasm accessions of Napier grass (pennisetum purpureum and P. purpureum x P. glaucum Hybrids) and comparison with farm clones using RAPD

Lowe, A.; Thorpe, W.; Teale, A.; Hanson, J.
Fonte: Kluwer Academic Publ Publicador: Kluwer Academic Publ
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
Relevância na Pesquisa
37.18%
Fifty six germplasm accessions of the important East African fodder crop Napier grass, Pennisetum purpureum, and its hybrids with P. glaucum, were characterised using 67 random amplified polymorphic DNA (RAPD) fragments. No or very low intra-accession variation was found for 49 of the accessions examined, confirming field observations that this species is predominantly clonally propagated. Comparison of intra and inter-accession variation identified several groups of identical/similar accessions that could be targeted if the collection is to be rationalised, and also highlighted two misplantings of germplasm material during transfer to a field trial site. A neighbour joining dendrogram of Jaccard's similarity estimates, clearly separated 50 accessions of P. purpureum from three P. glaucum individuals, and placed six hybrid accessions in an intermediate position. These groupings were well supported by a nested AMOVA (P<0.001; 29.5% of total variance due to taxonomic delineation). The main group of P. purpureum individuals could be further differentiated into five sub-groups (designated East Africa, Southern Africa, USA1, USA2 and Miscellaneous, to reflect the majority membership of sub-groups) and examination of the within P. purpureum component of the nested AMOVA...

The Gracilariaceae Germplasm Bank of the University of So Paulo, Brazil-a DNA barcoding approach

Costa, Emmanuelle S.; Plastino, Estela Maria; Petti, Rosario; Oliveira Filho, Eurico Cabral de; Oliveira, Mariana Cabral de
Fonte: SPRINGER; DORDRECHT Publicador: SPRINGER; DORDRECHT
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.11%
The University of So Paulo Gracilariaceae Germplasm Bank has 50 strains collected mostly in Brazil, but also elsewhere in the world. This bank has been used as a source of material for research developed locally and abroad. With over 200 species, some of which have high economic value, the family Gracilariaceae has been extensively studied. Nonetheless, taxonomic problems still persist by the existence of cryptic species, phenotypic plasticity, and broad geographic distribution. In the case of algae kept in culture for long periods of time, the identification is even more problematic as a consequence of considerable morphological modification. Thus, the use of molecular markers has been shown to be an efficient tool to elucidate taxonomic issues in the group. In this work, we sequenced the 5'-end of the cox1 gene for 41 strains and the universal plastid amplicon (UPA) plastid region for 45 strains, covering all 50 strains in the bank. In addition, the rbcL for representatives of the cox1/UPA clusters was sequenced for 14 strains. The original species identification based on morphology was compared with the molecular data obtained in this work, resulting in the identification of 13 different species. Our analyses indicate that cox1 and UPA are suitable markers for the delineation of species of Gracilariales in the germplasm bank. The addition of DNA barcode tags to the samples in the Gracilariaceae germplasm bank and the molecular identification of the species will make this bank even more useful for future research as the species can be easily traced and confirmed.; State of Sao Paulo Research Foundation (FAPESP); State of Sao Paulo Research Foundation (FAPESP) [2007/51270-7]; Brazilian National Council for Scientific and Technological Development (CNPq) [BrBOL 564945/2010-2]; Brazilian National Council for Scientific and Technological Development (CNPq); CAPES; CAPES

Genetic diversity of a brazilian wine grape germplasm collection based on morphoagronomic traits

Leão,Patrícia Coelho de S.; Cruz,Cosme Damião; Motoike,Sérgio Y.
Fonte: Sociedade Brasileira de Fruticultura Publicador: Sociedade Brasileira de Fruticultura
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
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The objectives of this study were to evaluate the performance of cultivars, to quantify the variability and to estimate the genetic distances of 66 wine grape accessions in the Grape Germplasm Bank of the EMBRAPA Semi-Arid, in Juazeiro, BA, Brazil, through the characterization of discrete and continuous phenotypic variables. Multivariate statistics, such as, principal components, Tocher's optimization procedure, and the graphic of the distance, were efficient in grouping more similar genotypes, according to their phenotypic characteristics. There was no agreement in the formation of groups between continuous and discrete morpho-agronomic traits, when Tocher's optimization procedure was used. Discrete variables allowed the separation of Vitis vinifera and hybrids in different groups. Significant positive correlations were observed between weight, length and width of bunches, and a negative correlation between titratable acidity and TSS/TTA. The major part (84.12%) of the total variation present in the original data was explained by the four principal components. The results revealed little variability between wine grape accessions in the Grape Germplasm Bank of Embrapa Semi-Arid.

Accessibility and exchange of plant germplasm by Embrapa

Bustamante,Patrícia Goulart; Ferreira,Francisco Ricardo
Fonte: Crop Breeding and Applied Biotechnology Publicador: Crop Breeding and Applied Biotechnology
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 EN
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This paper presents information about the organizational structure of Embrapa's banks and collections of plant germplasm and lists the 14 projects that comprise the Plant Genetic Resources Network which houses about 200 000 access and correspond to a collection of 300 genera, 787 species (90 % exotic). The main goal of the Plant Genetic Resources Network is being a source of variability for breeders of nationally and internationally research institutions. The paper also presents the different ways of knowing and accessing the collection of plant genetic resources maintained at Embrapa. Special emphasis is given to the way of the researchers can import and export plant germplasm, including presentation of a series of accessions exchanged in the last 35 years by Embrapa Genetic Resources and Biotechnology. The paper also provides the necessary documents and specifies the step-by-step to exchange and quarantine of germplasm held by Embrapa Genetic Resources and Biotechnology.

Diversidad genética en girasol cultivado: análisis de una colección de germoplasma local para su aplicación en programas de mejoramiento; Genetic diversity in sunflower: analysis of a local germplasm collection as a tool to assist management and breeding programs

Moreno, María Valeria
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2010 SPA
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37.02%
Los bancos de semillas ofrecen una valiosa fuente de diversidad para el mejoramiento genético de los cultivos. Para un aprovechamiento óptimo de los recursos genéticos, la caracterización fenotípica de los materiales conservados (resistencia a estreses bióticos y abióticos, índices de calidad química, nutricional y rendimiento, entre otros) debe ser acompañada por la caracterización genética de los mismos. De este modo, la diversidad alélica evaluada a través de marcadores moleculares es uno de los mejores indicadores del potencial genético de las entradas (accessions) de un banco. Los objetivos de este trabajo fueron: a) estudiar la diversidad genética en un conjunto de entradas de girasol cultivado preservadas en el Banco Activo de Germoplasma de INTA Manfredi (BAG-IM), b) estudiar la distribución de los polimorfismos detectados y la estructura poblacional, c) evaluar la consistencia entre metodologías de fenotipificación para el carácter de tolerancia a sequía, comparando ensayos de campo con ensayos en condiciones controladas, y d) analizar los patrones de variación nucleotídica en regiones candidatas asociadas al carácter tolerancia a déficit hídrico en líneas endocriadas pertenecientes al programa de mejoramiento de tolerancia a sequía del BAGIM. A fin de cuantificar los niveles de variabilidad se genotipificaron 337 individuos pertenecientes a 21 entradas representativas de las distintas categorías conservadas en el banco (líneas...

“Tertius gaudens” : germplasm exchange networks and agroecological knowledge among home gardeners in the Iberian Peninsula

Reyes García, Victoria; Molina, José Luis; Calvet Mir, Laura; Aceituno Mata, Laura; Lastra, Juan J.; Ontillera, Ricardo; Parada i Soler, Montserrat; Pardo de Santayana, Manuel; Rigat, Montse; Vallès, Joan; Garnatje i Roca, Ma. Teresa
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2013 ENG
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37.18%
Background: The idea that knowledge flows through social networks is implicit in research on traditional knowledge, but researchers have paid scant attention to the role of social networks in shaping its distribution. We bridge those two bodies of research and investigate a) the structure of network of exchange of plant propagation material (germplasm) and b) the relation between a person’s centrality in such network and his/her agroecological knowledge. Methods: We study 10 networks of germplasm exchange (n = 363) in mountain regions of the Iberian Peninsula. Data were collected through participant observation, semi-structured interviews, and a survey. Results: The networks display some structural characteristics (i.e., decentralization, presence of external actors) that could enhance the flow of knowledge and germplasm but also some characteristics that do not favor such flow (i.e., low density and fragmentation). We also find that a measure that captures the number of contacts of an individual in the germplasm exchange network is associated with the person’s agroecological knowledge. Conclusion: Our findings highlight the importance of social relations in the construction of traditional knowledge.