Crop Breeding and Applied Biotechnology

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12091

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Resultados da Pesquisa

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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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    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.