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Registros recuperados: 23
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A deterministic simulation study of embryo marker-assisted selection for age at first calving in Nellore (Bos indicus) beef cattle Genet. Mol. Biol.
Rosa,Artur J.M.; Bijma,Piter; Oliveira,Henrique N.; Lôbo,Raysildo B.; van Arendonk,Johan A.M..
We used deterministic simulation of four alternative multiple ovulation and embryo manipulation (MOET) closed nucleus schemes to investigate the benefits of using marker-assisted selection (MAS) of Nellore (Bos indicus) beef cattle embryos prior to transplantation to reduce the age at first calving (AFC). We found that MAS resulted in increased genetic gain as compared to selection without AFC quantitative trait loci (AFC-QTL) information. With single-stage selection the genetic response (GR) increased as follows: GR = 0.68% when the AFC-QTL explained 0.02 of the AFC additive genetic variance (sigma2A); GR = 1.76% for AFC-QTL explaining 0.05 sigma2A; GR = 3.7% for AFC-QTL explaining 0.1 sigma2A; and GR = 55.76% for AFC-QTL explaining 0.95 sigma2A. At the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Age at first calving; Beef cattle; Marker-assisted selection; Pre-selection; Quantitative trait loci.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000400008
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Alternative methodologies for genotyping polymorphisms in the CAST and CAPN1 genes in beef cattle R. Bras. Zootec.
Blecha,Isabella Maiumi Zaidan; Sousa,Isadora Inácio; Ferreira,Anna Beatriz Robottom; Feijó,Gelson Luis Dias; Torres Júnior,Roberto Augusto de Almeida; Siqueira,Fabiane.
ABSTRACT The objectives of this study were to genotype single nucleotide polymorphisms (SNP) AF159246:g.2959A>G (CAST/DdeI) and AF248054.2:g.6545C>T (CAPN4751) in beef cattle by PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism), using the restriction enzyme DdeI for both SNP, and describe the use of these genotyping methodologies for the first time. For the SNP located in the CAST gene, new primers were designed, and for the SNP of the CAPN1 gene, the same primers previously described in the literature were used. Bonsmara, Caracu, Senepol, Nelore, and Angus bulls were chosen from among the most used bulls in breeding programs according to their genealogy and the lowest possible degree of parentage between them to ensure...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Animal breeding; Marker-assisted selection; PCR-RFLP; SNP; Tenderness.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100311
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Association mapping in common bean revealed regions associated with Anthracnose and Angular Leaf Spot resistance Scientia Agricola
Fritsche-Neto,Roberto; Souza,Thiago Lívio Pessoa Oliveira de; Pereira,Helton Santos; Faria,Luís Cláudio de; Melo,Leonardo Cunha; Novaes,Evandro; Brum,Itaraju Junior Baracuhy; Jannink,Jean-Luc.
ABSTRACT: Despite important biotic stresses to common bean, Anthracnose (ANT) and Angular Leaf Spot (ALS) can cause losses of up to 80 % and occur in more than 60 countries around the world. Genetic resistance is the most sustainable strategy to manage these diseases. Thus, we aimed to (1) identify new SNP markers associated with ALS and ANT resistance loci in elite common bean lines, and (2) provide a functional characterization of the DNA sequences containing the identified SNP markers. We evaluated 60 inbred lines, under field conditions, which represent the elite germplasm developed by the Embrapa common bean breeding program across 22 years, in terms of severity of the ALS and ANT. The lines were genotyped with 5,398 SNPs. Then, a Mixed Linear Model...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Colletotrichum lindemuthianum; Pseudocercospora griseola; Disease resistance; Elite lines; Marker-assisted selection.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162019001400321
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Association of polymorphisms in the leptin and thyroglobulin genes with meat quality and carcass traits in beef cattle R. Bras. Zootec.
Carvalho,Thiago Dutra de; Siqueira,Fabiane; Torres Júnior,Roberto Augusto de Almeida; Medeiros,Sérgio Raposo de; Feijó,Gelson Luís Dias; Souza Junior,Maury Dorta de; Blecha,Isabella Maiumi Zaidan; Soares,Cleber Oliveira.
The objective of the present study was to estimate the allelic and genotypic frequencies of the polymorphisms E2FB (AY138588.1: c.305C> T), located in the leptin gene (LEP), and TG5 (X05380.1:g.-422C>T), located in the thyroglobulin gene (TG), and evaluate the association of these polymorphisms in crossbred cattle of seven distinct genetic groups with the following traits: slaughter weight (SW), hot carcass weight (HCW), hot carcass yield (HCY), carcass fat thickness (CFT), ribeye area (REA), marbling (MARM) and shear force (SF). The animals were genotyped using the PCR-RFLP (Polymorphism Chain Reaction-Restriction Fragment Length Polymorphism) technique, using 201 products obtained from F1 Caracu × Nellore, Angus × Nellore and Valdostana × Nellore...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Fat thickness; Marker-assisted selection; Meat tenderness; Shear force; SNP.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012001000004
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Association of the bovine major histocompatibility complex (BoLA) BoLA-DRB3 gene with fat and protein production and somatic cell score in Brazilian Gyr dairy cattle (Bos indicus) Genet. Mol. Biol.
Nascimento,Carlos Souza do; Machado,Marco Antonio; Martinez,Mario Luiz; Silva,Marcos Vinícius G. Barbosa da; Guimarães,Marta Fonseca Martins; Campos,Ana Lúcia; Azevedo,Ana Luisa Sousa; Teodoro,Roberto Luiz; Verneque,Rui da Silva; Guimarães,Simone Eliza Facioni; Oliveira,Denise Aparecida Andrade.
The effect of the bovine major histocompatibility complex (BoLA) locus on animal health may be due to a direct action of its alleles on immune functions, whereas its indirect effect on production traits might be explained by the better general health conditions of more productive animals. In the present study, the BoLA-DRB3 gene was investigated in 1058 cows belonging to seven Brazilian Gyr Dairy herds (Bos indicus, Zebu cattle). A total of 37 alleles were identified, 15 of them described for the first time in a Zebu breed. A highly significant association (p < 0.02) was observed between allele *54 and a decrease (-26.1 kg) in milk protein yield and there was a significant association (p < 0.05) between this allele and lower (-26.07 kg) milk fat...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cattle; Marker-assisted selection; Molecular markers; PCR-RFLP.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000400011
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Detection of a novel quantitative trait locus for cold tolerance at the booting stage derived from a tropical japonica rice variety Silewah OAK
Mori, Masahiko; Onishi, Kazumitsu; Tokizono, Yoshiro; Shinada, Hiroshi; Yoshimura, Toru; Numao, Yoshinori; Miura, Hideho; Sato, Takashi; 大西, 一光; 三浦, 秀穂.
Cold stress at the booting stage in rice induces spikelet sterility because of aberrant microspore development, which often seriously damages seed production. Some breeding lines with high cold tolerance were developed by using tropical japonica variety Silewah as a donor of cold tolerance; however, the genetic factors that confer cold tolerance of this variety have not been comprehensively analyzed. In this study, phenotypic and molecular characterization of novel cold-tolerant strains derived from crosses with Silewah was performed to identify quantitative trait loci (QTLs) responsible for cold tolerance. Molecular marker analysis revealed that 2 cold-tolerant strains carried chromosomal segments of Silewah at the same genomic regions on chromosomes 3, 4...
Palavras-chave: Oryza sativa; Cold tolerance; Booting stage; QTL; Phenotypic selection; Marker-assisted selection; Exotic germplasm.
Ano: 2011 URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3040
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Development and application of high-throughput amplified fragment length polymorphism technique in Calluna vulgaris (Ericaceae) Electron. J. Biotechnol.
Borchert,Thomas; Gawenda,Inka.
Calluna vulgaris is an important ornamental crop of the horticultural industry in Europe. In order to improve breeding of this species, especially of the most important trait of &#8216;bud-flowering', the implementation of molecular techniques that allow rapid, reproducible and efficient screening of whole segregating populations e.g. for molecular marker and mapping approaches is a requirement. We therefore aimed to introduce the powerful tool of amplified fragment length polymorphisms (AFLP®), a widely and successfully applied method, into our methodological assortment. As an essential prerequisite, the isolated DNA should be of adequate quality which is a common obstacle when dealing with woody species and their interfering secondary...
Tipo: Journal article Palavras-chave: DNA content; Mapping; Marker-assisted selection; Ornamental; Plant tissue.
Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000200007
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Diversity of microsatellites linked to the FSHbeta gene, their usefulness for individual identification and association with reproductive performance Ciência Rural
Duarte,Letícia Becker Homrich; Moraes,José Carlos Ferrugem; Weimer,Tania de Azevedo.
The genetic diversity of three microsatellites (ILSTS027, MBO22, BM4325) mapped on the bovine chromosome 15 and linked to the follicle-stimulating hormone beta gene (FSHß) was investigated in cows of a Brangus Ibagé herd and the efficiency of these markers for individual identification and parentage control was estimated. Possible associations between each molecular marker and cow reproductive performance were also analyzed. Six alleles were detected in BM4325 and ILSTS027 and 12 in MB022, the most frequent being BM4325*101, BM4325*103, ILSTS027*169 and MB022*229. Polymorphic information content ranged from 0.58 to 0.88 while expected heterozygosity ranged from 65% to 89%, with an average mean value of 77%. Although only three markers were studied, the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Microsatellites; Bovine genetic diversity; Individual identification; Reproductive performance; Marker-assisted selection.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782005000100023
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Efficiency in evaluating salt tolerance in rice using phenotypic and marker assisted selection International Rice Research Institute
Bhuiyan, Md. A.R..
xvi, 96 p. : ill. Thesis (Ph.D.) -- Bangladesh Agricultural University.
Tipo: Thesis Palavras-chave: Rice; Plant genetics; Salt tolerance; Selection methods; Marker-assisted selection; Plant breeding.
Ano: 2005 URL: http://hdl.handle.net/10269/179
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Estimation by simulation of the efficiency of the French marker assisted selection program in dairy cattle Inra
Guillaume, F.; Fritz; Boichard, D.; Druet, T..
Tipo: Journal Article Palavras-chave: Marker-assisted selection; Simulation; Efficiency; Dairy cattle.
Ano: 2008 URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD2008f2993140&uri=/notices/prodinra1/2009/12/
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Genetic characterization of coat color genes in Brazilian Crioula sheep from a conservation nucleus PAB
Cavalcanti,Lilian Cristina Gomes; Moraes,José Carlos Ferrugem; Faria,Danielle Assis de; McManus,Concepta Margaret; Nepomuceno,Alcebiades Renato; Souza,Carlos José Hoff de; Caetano,Alexandre Rodrigues; Paiva,Samuel Rezende.
Abstract: The objective of this work was to identify single nucleotide polymorphisms (SNPs) in resequencing data from MC1R, ASIP, and TYRP1 genes derived from Crioula sheep (Ovis aris) with different coat colors. Polymorphisms in the ASIP (agouti-signaling protein), MC1R (melanocortin 1 receptor), and TRYP1 (tyrosinase-related protein 1) genes were analyzed in 115 sheep from Embrapa’s conservation nucleus of crioula sheep, in Brazil. A total of 7,914 bp were sequenced per animal, and 14 SNPs were identified. Two additional assays were performed to detect duplications and deletions in the ASIP gene. Ninety-five percent of the coat color variation was explained by epistatic interactions observed between specific alleles in the MC1R and ASIP genes. Evidence...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Ovis aris; ASIP; Genetic resources conservation; Marker-assisted selection; MC1R; TYRP1.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017000800615
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Genetic linkage map and mapping of the locus of biological nitrogen fixation inefficiency in cowpea Agronomy
Seido, Sirando Lima; Fernandes Santos, Carlos Antonio.
The objectives of the present study were to construct a cowpea genetic map using the F2 population resulting from the cross IC-1 x BRS Marataoã, based on single nucleotide polymorphism (SNP) markers, and to map the cpi gene, with additional reference to introgression with the consensus map of species, aiming to identify markers for assisted selection to develop more efficient cultivars for BNF. The parents and 89 F2 plants were genotyped with 51,128 SNP markers, of which 910 polymorphic markers were used to construct the map. The results revealed 11 linkage groups, with an average of 82 markers per chromosome and average distance of 1.26 cM between markers. Recombination analysis of the SNPs indicated that markers 2_12850 and 2_00188, located in linkage...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Vigna unguiculata; Nitrogen fixation; Marker-assisted selection.
Ano: 2019 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/42603
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Genetic relationship, molecular mapping, and development of marker-assisted selection for fertility restoring (RF) genes for rice cytoplasmic male sterility systems International Rice Research Institute
Sattari, Majid.
xiii, 104 l. : ill. Thesis (Ph.D.) -- University of the Philippines at Los Baños
Tipo: Thesis Palavras-chave: Rice; Plant genetics; Chromosome mapping; Marker-assisted selection; Plant fertility; Cytoplasmic male sterility; Hybrids.
Ano: 2004 URL: http://hdl.handle.net/123456789/379
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Genetics of coffee quality Braz. J. Plant Physiol.
Leroy,Thierry; Ribeyre,Fabienne; Bertrand,Benóit; Charmetant,Pierre; Dufour,Magali; Montagnon,Christophe; Marraccini,Pierre; Pot,David.
Coffee quality, in the present context of overproduction worldwide, has to be considered as a main selection criterion for coffee improvement. After a definition of quality, and an overview of the non genetic factors affecting its variation, this review focuses on the genetic factors involved in the control of coffee quality variation. Regarding the complexity of this trait, the different types of quality are first presented. Then, the great variation within and between coffee species is underlined, mainly for biochemical compounds related to quality (caffeine, sugars, chlorogenic acids, lipids). The ways for breeding quality traits for cultivated species, Coffea arabica and Coffea canephora are discussed, with specific challenges for each species. For C....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Coffea spp.; Biochemical compounds; Candidate genes; ESTs; Genetic breeding; Marker-assisted selection; Quality.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100016
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Identification of the Er1 resistence gene and RNase S-alleles in Malus prunifolia var. ringo rootstock Scientia Agricola
Agapito-Tenfen,Sarah Zanon; Dantas,Adriana Cibele de Mesquita; Denardi,Frederico; Nodari,Rubens Onofre.
Woolly apple aphid (WAA; Eriosoma lanigerum Hausm.) is a major insect pest that has significant economic impact on apple growers worldwide. Modern breeding technologies rely on several molecular tools to help breeders select genetic determinants for traits of interest. Consequently, there is a need for specific markers linked to the genes of interest. Apple scions and rootstocks have an additional barrier to the introduction of pest resistance genes due to the presence of self-incompatibility S-RNase alleles. The genetic characterization and early identification of these alleles can amplify the contribution of a breeding program to the selection of resistant genitors that are as compatible as possible. In this study, we identified the Er1 gene involved in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Malus pumila; Woolly apple aphid; Self-incompatibility; Bulk segregant analysis; Marker-assisted selection.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000100062
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Improving durum wheat (Triticum turgidum L. var durum) grain yellow pigment content through plant breeding Ciencia e Investigación Agraria
Schulthess,Albert; Schwember,Andrés R.
A. Schulthess, and A.R. Schwember. 2013. Improving durum wheat (Triticum turgidum L. var durum) grain yellow pigment content through plant breeding. Cien Inv. 40(3): 475-490. Wheat grain yellow pigment content (GYPC) is an important trait that determines pasta quality. The main objective of this review is to examine the genetics regulating GYPC to enhance it through breeding, leading to improved pasta quality. Although GYPC is a polygenic trait, its high heritability has facilitated breeding internationally. GYPC is influenced by one or two major loci with additive effects plus several minor genes, and there is evidence showing that the phytoene synthase loci PSY1A and PSY1B are strong candidate genes that regulate GYPC. Nine Chilean durum wheat (Triticum...
Tipo: Journal article Palavras-chave: Durum wheat; Grain yellow pigment content; Improved color; PSY1A; PSY1B; Backcrossing; Marker-assisted selection.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202013000300002
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Interaction between estrogen receptor and retinol-binding protein-4 polymorphisms as a tool for the selection of prolific pigs Genet. Mol. Biol.
Gonçalves,Iara Denise Vasconcellos; Gonçalves,Paulo Bayard Dias; Silva,Janandra Cortese da; Portela Jr,Valério Valdetar; Borges,Luiz Felipe Kruel; Oliveira,João Francisco Coelho; Lovatto,Paulo Alberto.
The aim of the present study was to investigate the association of the estrogen receptor (ER-PvuII) and retinol-binding protein 4 (RBP4-MspI) gene polymorphisms and their interactions with prolificacy in a commercial synthetic pig line reared in Brazil. A total of 10,374 piglet records from 218 sows and 817 litters were used for litter size analysis. Only females with three or four farrowings were included in the analysis. The mean litter size ranged from 5.0 to 19.5 piglets. DNA was extracted from leukocytes by a standard method, and ER-PvuII and RBP4-MspI polymorphisms were characterized by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The association between alleles or genotypes and reproductive performance...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Swine; Marker-assisted selection; Retinol-binding protein-4; Estrogen receptor.
Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000300014
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Mapping aluminum tolerance loci in cereals: A tool available for crop breeding Electron. J. Biotechnol.
Inostroza-Blancheteau,Claudio; Soto,Braulio; Ibáñez,Cristian; Ulloa,Pilar; Aquea,Felipe; Arce-Johnson,Patricio; Reyes-Díaz,Marjorie.
Aluminum (Al) toxicity is the main factor limiting crop productivity in acidic soils around the world. In cereals, this problem reduces crop yields by 30-40%. The use of DNA-based markers linked to phenotypic traits is an interesting alternative approach. Strategies such as molecular marker-assisted selection (MAS) in conjunction with bioinformatics-based tools such as graphical genotypes (GGT) have been important for confirming introgression of genes or genomic regions in cereals but also to reduce the time and cost of identifying them through genetic selection. These biotechnologies also make it possible to identify target genes or quantitative trait loci (QTL) that can be potentially used in similar crops to increase their productivity. This review...
Tipo: Journal article Palavras-chave: Aluminum tolerance; ALMT1; Cereals; Marker-assisted selection; Organic acid.
Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000400011
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Microsatellite-assisted backcross selection in maize Genet. Mol. Biol.
Benchimol,Luciana Lasry; Souza Jr.,Cláudio Lopes de; Souza,Anete Pereira de.
A microsatellite marker (SSR) was chosen to simulate a target allele and three criteria (02, 04 and 06 markers per chromosome) were tested to evaluate the most efficient parameters for performing marker-assisted backcross (MAB) selection. We used 53 polymorphic SSRs to genotype 186 BC1 maize (Zea mays L.) plants produced by crossing the inbred maize lines L-08-05 (donor parent) and L-14-4B (recurrent parent). The second backcross (BC2) generation was produced with 180 plants and screened with markers which were not recovered from the first backcross (BC1) generation. A total of 480 plants were evaluated in the third backcross (BC3) generation from which 48 plants were selected for parental genotype recovery. Recurrent genotype recovery averages in three...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Maize; Marker-assisted backcrossing (MAB); Marker-assisted selection; Microsatellites.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000500022
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QTLs for resistance to soybean cyst nematode, races 3, 9, and 14 in cultivar Hartwig PAB
Ferreira,Marcia Flores da Silva; Cervigni,Gerardo Domingo Lucio; Ferreira,Adésio; Schuster,Ivan; Santana,Fernanda Abreu; Pereira,Waldir Dias; Barros,Everaldo Gonçalves de; Moreira,Maurilio Alves.
The objective of this work was to identify major and minor-effect quantitative trait loci (QTL) for resistance to races 3, 9, and 14 of soybean cyst nematode (SCN) in Hartwig cultivar; to map new resistance QTLs for these races; and to check for the existence of epistatic interactions between QTLs. Cultivar Hartwig is an important resistance source to SCN. Recombinant inbred lines (RIL) obtained from a cross between 'Hartwig' (resistant) and Y23 (susceptible) were evaluated regarding resistance to the three races. New genomic regions for resistance to SCN were identified by microsatellites. Four QTLs, which explained between 12 and 34% of phenotypic variance, were detected for resistance to race 3 in linkage groups (LG) A2, G, J, and M. The QTL in LG G is...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max; Breeding; Marker-assisted selection; Molecular markers.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2011000400012
Registros recuperados: 23
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