Biblioteca do Café
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1
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Item Reproducibility of the RAPD marker and its efficiency in coffee tree genotype grouping analysis(Crop Breeding and Applied Biotechnology, 2002) Sakiyama, Ney Sussumu; Teixeira-Cabral, Terezinha Aparecida; Zambolim, Laércio; Pereira, Antonio Alves; Barros, Everaldo Gonçalves; Sakiyama, Cássia Camargo HargerThe genetic diversity of Coffea arabic L. cultivars is relatively narrow and its assessment and increase is important for breeding. Fifty two arbitrary primers were used to evaluate the reproducibility and the influence of the number of RAPD (Random Amplified Polymorphic DNA) markers on the estimation of genetic distances among 40 genotypes of Coffea spp. The average number of polymorphic bands was 6.69 per primer among all genotypes, and 1.27 among arabica coffee genotypes. RAPD markers were efficient in estimating the genetic distances among the genotypes. The increase in RAPD loci number during grouping analysis did not affect the major groups’ composition; however, it affected the composition of subgroups. Marker reproducibility was 76.88% and replicated data was recommended for distinguishing genotypes with the same genetic background.Item Characterization of differential coffee tree hostsfor Hemileia vastatrix Berk. et Br. with RAPD markers(Crop Breeding and Applied Biotechnology, 2004-03-12) Teixeira-Cabral, Terezinha Aparecida; Sakiyama, Ney Sussumu; Zambolim, Laércio; Barros, Everaldo Gonçalves de; Silva, Dalza Gomes daEighteen clones of differential coffee tree hosts for Hemileia vastatrix Berk. et Br. were characterized with RAPD markers. The genetic distances were estimated and the genealogical origin of the clones compared to data of markerbased clusters. Thirty-five primers identified 158 polymorphic loci of RAPD markers. The cluster based on the matrix of genetic dissimilarity values was compatible with information on the genealogical origin cited in literature. Specific markers for a number of clones were identified, and a combination of 12 RAPD markers allowed the characterization of the studied clones.Item 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 AlvesCoffee 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.Item Esporulação de isolados de Cercospora coffeicola Berk. & Cooke provenientes de diferentes espécies hospedeiras(Embrapa Café, 2015) Botelho, Deila Magna dos Santos; Resende, Mário Lúcio Vilela de; Vale, Paula Adrielly Souza; Monteiro, Ana Cristina Andrade; Vilela, Rossiane de Oliveira; Ribeiro, Ingridy Simone; Patrício, Flávia Rodrigues Alves; Zambolim, LaércioCercospora coffeicola é um fungo que afeta plantas do gênero Coffea e causa prejuízos a cultura do cafeeiro. A esporulação de C. coffeicola é influenciada pela composição do meio de cultura e luminosidade, entretanto informações sobre a influência da espécie hospedeira na esporulação do patógeno são escassas. Com isto, o objetivo do presente trabalho foi avaliar a esporulação de isolados de C. coffeicola obtidos das espécies Coffea arabica, C. canephora, C. stenophylla e C. liberica var. dewerei. Para obtenção de esporos dos diferentes isolados, disco de micélio das colônias foram macerados, submetidos a agitação pelo período de quatro dias e posteriormente colocados em BOD por quatro dias para secagem das placas. A esporulação foi quantificada com hemancitometro. O delineamento experimental utilizado foi inteiramente casualizados com quatro tratamentos (C. arabica, C. canephora, C. stenophylla e C. liberica var. dewerei) e cinco repetições. Os isolados de C. coffeicola obtidos das diferentes espécies hospedeiras apresentaram variação na esporulação em que maiores valores foram observados nos isolados obtidos das espécies C. stenophylla e C. liberica var. dewerei e o menor no isolado proveniente da espécie C. canephora.