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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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    Prediction of genetic gains from selection in Arabica coffee progenies
    (Crop Breeding and Applied Biotechnology, 2011-09-08) Oliveira, Antonio Carlos Baião de; Pereira, Antonio Alves; Silva, Felipe Lopes da; Rezende, Juliana Costa de; Botelho, César Elias; Carvalho, Gladyston Rodrigues
    Gains from selection for yield were estimated in Arabica coffee progenies carrying rust-resistance genes. The experiment in augmented block design was installed in Três Pontas, state of Minas Gerais. Three blocks were established with six plants per plot, spaced 3.50 x 0.90 m, in 96 regular (F2 progenies) and two control treatments. The plant response to rust was evaluated on a grade scale in 2008. Yield (bags per hectare) was estimated in the growing seasons 2005 to 2008. Significant differences between treatments for yield were observed in all harvests, except 2005. The presence of genetic variability among progenies allowed significant gain from selection for yield. Under the experimental conditions of this study, selection for yield can be performed in the first high-yield year, without major losses compared to genetic gain from selection for yield when based on the mean of four harvests.
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    Partial map of Coffea arabica L. and recovery of the recurrent parent in backcross progenies
    (Crop Breeding and Applied Biotechnology, 2007-06-30) Oliveira, Antonio Carlos Baião de; Sakiyama, Ney Sussumu; Caixeta, Eveline Teixeira; Zambolim, Eunize Maciel; Rufino, Raphael José Nascif; Zambolim, Laércio
    A partial map of Coffea arabica L. was constructed based on a backcross population and RAPD markers. From a total of 178 markers evaluated, only 134 that segregated 1:1 (P>0.05) were used to develop the map. Seventeen markers were not linked, while 117 formed 11 linkage groups, covering a genome distance of 803.2 cM. The maximum distance between adjacent markers was 26.9 cM, and only seven intervals exceeded 20 cM. The markers were further used for assisted selection of the plants closest to the recurrent parent, to accelerate the introgression of rust resistance genes in the coffee breeding program. Three BC1 plants resistant to coffee leaf rust and with high genetic similarity to ?Catuaí? were selected and integrated in the following backcross cycles.
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    Estimates of genetic parameters in Arabic coffee derived from the Timor hybrid
    (Crop Breeding and Applied Biotechnology, 2007-06-30) Mistro, Júlio César; Fazuoli, Luiz Carlos; Gallo, Paulo Boller; Oliveira, Antonio Carlos Baião de; Toma-Braghini, Masako; Silvarolla, Maria Bernadete
    Genetic parameters of Arabic coffee progenies derived from the cross Villa Sarchi x Timor hybrid were estimated in order to evaluate their potential for improvement. The experiment was installed in a random block design with ten treatments, eight replicates and eight plants per plot. The parameters cherry yield, plant height, canopy diameter, seed types and sizes were estimated. Results demonstrated significant differences between treatments for all traits. Greatest yield gains were achieved when the selection was performed based on plot means and in years of high yields. The variation index b was the best indicator of genetic variability. The progenies IAC 3786. IAC 3788, IAC 4094, IAC 4095, IAC 3425, and IAC 3429 were outstanding regarding the evaluated agronomic traits, representing progenies of high agronomic potential. All progenies presented leaf rust resistance.
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    Sensory quality of Coffea arabica L. genotypes influenced by postharvest processing
    (Crop Breeding and Applied Biotechnology, 2019) Barbosa, Ivan de Paiva; Oliveira, Antonio Carlos Baião de; Rosado, Renato Domiciano Silva; Sakiyama, Ney Sussumu; Cruz, Cosme Damião; Pereira, Antônio Alves
    The specialty coffee market has grown significantly in the past decades and has several cultivars with productive potential. The objective of this study was to evaluate the sensory profile of the beverage produced from Coffea arabica L. genotypes based on postharvest processing and to identify cultivars with the greatest genetic potential for coffee cultivation in the city of Araponga, Minas Gerais, Brazil. The experiment was a randomized complete block design with two replicates and 11 genotypes with different levels of resistance to rust. The sensory profile demonstrated an interaction between the genotype and the processing technique. Five of the genotypes presented total scores above 85 points according to the SCAA protocol. Moreover, two of these genotypes yielded heightened sensory notes after undergoing dry processing. The selection of coffee genotypes should consider the level of technology involved in the drying of the coffee beans, which preserves the potential quality of the beverage.
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    Triple plagiotropic branch in coffee: a new promising mutant?
    (Crop Breeding and Applied Biotechnology, 2017-10) Sakiyama, Ney Sussumu; Picoli, Edgard Augusto de Toledo; Oliveira, Antonio Carlos Baião de; Caixeta, Eveline Teixeira; Zambolim, Laércio; Martinez, Hermínia Emília Prieto; Pereira, Antonio Alves
    Coffee tree is a shrub with dimorphic branches. The orthotropic stem grows vertically with two near-horizontal plagiotropic branches, per node, in opposite phyllotaxy. The consecutive nodes of the orthotropic stem are organ- ized in parastichies. We report here mutant plants of Coffea arabica with triple plagiotropic branch, resulted from the whorled phyllotaxy of the orthotropic stem. In mutant plants three plagiotropic branches in the same node are sepa- rated by angles of approximately 120 o , while in normal plants two plagiotropic branches in the same node are separated by angles of approximately 180 o . In mutant plants the angles of the parastichies increase approximately 50 o clock- wise between consecutive nodes, while in normal plants the angles increase approximately 87 o . The plant architecture is changed. The triple plagiotropic branch is a putative mutant with potential to be explored in coffee breeding programs. The hypotheses for the origin of the mutation and the research perspectives are discussed.
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    Prediction of genetic gains from selection in arabica coffee progenies
    (Crop Breeding and Applied Biotechnology, 2011-06) Oliveira, Antonio Carlos Baião de; Pereira, Antonio Alves; Silva, Felipe Lopes da; Rezende, Juliana Costa de; Botelho, César Elias; Carvalho, Gladyston Rodrigues
    Gains from selection for yield were estimated in Arabica coffee progenies carrying rust-resistance genes. The experiment in augmented block design was installed in Três Pontas, state of Minas Gerais. Three blocks were established with six plants per plot, spaced 3.50 x 0.90 m, in 96 regular (F 2 progenies) and two control treatments. The plant response to rust was evaluated on a grade scale in 2008. Yield (bags per hectare) was estimated in the growing seasons 2005 to 2008. Significant differences between treatments for yield were observed in all harvests, except 2005. The presence of genetic variability among progenies allowed significant gain from selection for yield. Under the experimental conditions of this study, selection for yield can be performed in the first high-yield year, without major losses compared to genetic gain from selection for yield when based on the mean of four harvests.
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    Selection of arabica coffee progenies tolerant to heat stress
    (Universidade Federal de Santa Maria, 2015-07) Teixeira, Alexsandro Lara; Souza, Flávio de França; Pereira, Antonio Alves; Oliveira, Antonio Carlos Baião de; Rocha, Rodrigo Barros
    Due to high temperatures, practically all coffee farms in the state of Rondonia are of the C. canephora species. Thus, importing arabica coffee from other states becomes necessary for composition of blends, as well as for the specialty or gourmet coffee market. The purpose of this study was to select arabica coffee genotypes that exhibit satisfactory agronomic performance under high temperature conditions. The experiment was conducted in Ouro Preto do Oeste, RO, Brazil, with mean annual temperature of 25.8°C and mean annual rainfall of 2300mm year -1 . The experiment was composed of 114 arabica coffee genotypes, with 103 progenies and eleven control cultivars, provided by EPAMIG. A randomized block experimental design was used with three replications, spacing of 3.0x1.0 meters and five plants per plot. All the crop seasons showed significant difference for the green coffee yield trait. In joint analysis, significant differences were detected among progenies and control cultivars. In the average of the four harvests, green coffee yield was 32.38 bags ha -1 . The cultivars ‘Catuaí Vermelho IAC 15’, ‘Obatã IAC 1669-20’ and ‘Catucaí Amarelo 2SLCAK’ stood out, achieving yields greater than 40 bags ha -1 . The gain obtained from selection was 14.33 bags ha -1 , which is equivalent to an increase of 44.04% in production of green coffee. The progeny H514-7-10-6-2-3-9 stood out with an average yield of 51.20 bags ha -1 . In regard to maturation cycle, 56% of the progenies were classified as early maturity and 44% as medium maturity. Late maturity genotypes were not observed.
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    Divergência genética entre progênies de café robusta
    (Instituto Agronômico (IAC), 2008-10) Ivoglo, Milana Gonçalves; Fazuoli, Luiz Carlos; Oliveira, Antonio Carlos Baião de; Gallo, Paulo Boller; Mistro, Júlio César; Silvarolla, Maria Bernadete; Toma-Braghini, Masako
    Estudou-se a divergência genética de 21 progênies de meios-irmãos - 19 do grupo Congolês e duas do grupo Guineano - de introduções do germoplasma de café robusta (Coffea canephora) do IAC. O estudo baseou-se em análises multivariadas de 14 características morfo-agronômicas, com o propósito de selecionar as progênies mais divergentes, visando à definição de população-base para posterior seleção e produção de híbridos. Avaliou-se também a importância das características discriminantes para análises de divergência, visando ao descarte das variáveis, segundo suas contribuições relativas. O experimento foi plantado e desenvolvido em campo experimental localizado no Pólo Regional do Nordeste Paulista, Mococa (SP), em blocos casualizados, com 21 tratamentos e 24 repetições. O agrupamento dos genótipos foi realizado com base nos métodos de Tocher e UPGMA. A matriz de dissimilaridade genética foi obtida por meio da distância generalizada de Mahalanobis, que serviu de base para a formação dos grupos. Os métodos empregados foram eficientes em detectar ampla variabilidade genética entre as progênies avaliadas. Vários grupos dissimilares foram identificados. As progênies IAC 2262, IAC 2290, IAC 2286, IAC 2292 e IAC 2291 são indicadas para compor programas de intercruzamentos, por terem sido consideradas as mais promissoras na obtenção de populações segregantes ou híbridos heteróticos. As características que menos contribuíram para a divergência genética foram, hierarquicamente: diâmetro da copa antes da poda, altura da planta antes da poda e área foliar.
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    Desempenho agronômico de cultivares de café resistentes à ferrugem no Estado de Minas Gerais, Brasil
    (Instituto Agronômico (IAC), 2012-10) Carvalho, Alex Mendonça de; Mendes, Antônio Nazareno Guimarães; Botelho, Cesar Elias; Oliveira, Antonio Carlos Baião de; Rezende, Juliana Costa de; Rezende, Ramiro Machado
    Objetivou-se no trabalho avaliar o comportamento de 24 cultivares de cafeeiro, sendo 22 resistentes à ferrugem e duas testemunhas suscetíveis, em diferentes ambientes de Minas Gerais, a fim de contribuir para a recomendação técnica. Os experimentos foram instalados em quatro municípios (Lavras, Campos Altos, Patrocínio e Turmalina). O delineamento experimental utilizado foi o de blocos casualizados com três repetições, no espaçamento de 3,5x0,7 m e parcelas de dez plantas. As avaliações de produtividade, porcentagem de grãos classificados em peneira 16 acima e vigor vegetativo referem-se a quatro colheitas (2008 a 2012). Foram avaliadas, também, a adaptabilidade e estabilidade da produtividade das cultivares. As cultivares Sabiá Tardio, Pau Brasil MG1, Obatã IAC 1669-20, Catucaí Amarelo 24/137 e IPR 103 são promissoras para as referidas regiões cafeeiras. Essas cultivares aliam estabilidade e adaptabilidade independentemente do ambiente, com desempenho agronômico superior.
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    Integração de dados quantitativos e multicategóricos na determinação da divergência genética entre acessos de cafeeiro
    (Instituto Agronômico (IAC), 2013-07) Silva, Felipe Lopes da; Baffa, David Carlos Ferreira; Oliveira, Antonio Carlos Baião de; Pereira, Antonio Alves; Bonomo, Vitor Santos
    Foi realizada estratégia de integração dos dados quantitativos e multicategóricos para avaliação da divergência genética entre 88 acessos de Coffea arabica. Avaliaram-se 12 características quantitativas (nota total da qualidade sensorial da bebida; peso de três litros de “café da roça”; peso de três litros de “café da roça” com 11% de umidade; porcentagem de café beneficiado a partir de três litros de “café da roça” com 11% de umidade; peso de três litros de café beneficiado com 11% de umidade; total de frutos de “café da roça” em um litro; porcentagem de frutos secos, passas, cereja, verde-cana e verdes em um litro de “café da roça”; e porcentagem de frutos com lojas vazias em um litro de “café da roça”) e seis características multicategóricas relacionadas à qualidade sensorial da bebida (doçura, acidez, corpo, sabor, retrogosto e aspecto geral). Baixa divergência genética foi encontrada entre os acessos considerando as características quantitativas e multicategóricas isoladamente. No entanto, com a conversão dos dados quantitativos em multicategóricos, a integração de características de diferentes naturezas favoreceu a melhor visualização da divergência genética entre os acessos avaliados, devido ao maior número de grupos formados em comparação ao agrupamento para cada conjunto de características.