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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Polymorphic information content of SSR markers for Coffea spp.(Crop Breeding and Applied Biotechnology, 2010) Caixeta, Eveline Teixera; Missio, Robson Fernando; Zambolim, Eunize Maciel; Zambolim, Laércio; Cruz, Cosme Damião; Sakiyama, Ney SussumuThirty-three coffee SSR primers from enriched genomic library with (GT)15 and (AGG)10 repeats were analyzed in 24 coffee tree accessions. Twenty-two primers were polymorphic among accessions; the number of alleles ranged from 2 to 13, with the mean number of 5.1 alleles per primer. PIC values ranged from 0.08 to 0.79. The highest mean PIC values were found for C. canephora (0.46), and the lowest values for C. arabica (0.22) and triploids (0.22) accessions. The polymorphic SSR markers used in this study were useful for genetic fingerprinting in the coffee tree, especially in the C. canephora and the leaf rust resistant arabica cultivars.Item 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, LaércioA 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.Item Molecular diversity in Coffea canephora germplasm conserved and cultivated in Brazil(Crop Breeding and Applied Biotechnology, 2013-12) Souza, Flávio de França; Caixeta, Eveline Teixeira; Ferrão, Luís Felipe Ventorim; Pena, Guilherme Ferreira; Sakiyama, Ney Sussumu; Zambolim, Eunize Maciel; Zambolim, Laércio; Cruz, Cosme DamiãoThis work aimed to characterize accessions that represent the C. canephora germplasm conserved and cultivated in Brazil. A total of 130 accessions from germplasm banks of IAC (São Paulo), UFV (Minas Gerais) and also collected in plantations of the State of Espírito Santo and Rondônia were evaluated with a set of 20 new microsatellite primers. Multivariate methods were used to estimate the relationship among the accessions. High level of polymorphism and two major diversity clusters were identified. First cluster was composed by the accessions conserved in the IAC and UFV collections and the second was formed by accessions collected in areas under cultivation. Accessions from Espírito Santo and Rondônia were clear separated, composing two subclusters. Despite the great polymorphism found in Brazilian plantations, the diversity may be increased, because a new threshold in the genetic gains is expected on breeding programs with the intensification of the use of conserved germplasmItem Breeding potential and genetic diversity of “Híbrido do Timor” coffee evaluated by molecular markers(Crop Breeding and Applied Biotechnology, 2010-06-20) Setotaw, Tesfahun Alemu; Caixeta, Eveline Teixeira; Pena, Guilherme Ferreira; Zambolim, Eunize Maciel; Pereira, Antonio Alves; Sakiyama, Ney SussumuAFLP, RAPD and SSR molecular markers were used to study the genetic diversity and genetic structure of the Híbrido de Timor germplasm. The principal coordinate analysis, UPGMA cluster analysis based on genetic dissimilarity of Jaccard, Bayesian model-based cluster analysis, percentage of polymorphic loci, Shannon’s information index and Nei gene diversity were employed to assess the genetic diversity. The analyses demonstrated a high genetic diversity among Híbrido de Timor accessions. UPGMA and Bayesian cluster analyses grouped the accessions into three clusters. The genetic structure of Híbrido de Timor is reported. The management of Híbrido de Timor germplasm variability and its potential use in breeding programs are discussed.Item Herança da resistência do Híbrido de Timor UFV 443-03 à ferrugem-do-cafeeiro(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2009-03) Capucho, Alexandre Sandri; Caixeta, Eveline Teixeira; Zambolim, Eunize Maciel; Zambolim, LaércioO objetivo deste trabalho foi caracterizar a herança da resistência do Híbrido de Timor UFV 443-03 à ferrugem-do-cafeeiro (Hemileia vastatrix). Para isso, a raça II e o patótipo 001 de ferrugem foram inoculados em 246 plantas da população F 2 , 115 plantas do retrocruzamento suscetível (RC S ) e 87 plantas do retrocruzamento resistente (RC R ), originadas do cruzamento entre o genótipo suscetível cv. Catuaí Amarelo IAC 64 e a fonte de resistência Híbrido de Timor UFV 443-03. Para ambos os inóculos, a cv. Catuaí Amarelo IAC 64 foi suscetível, enquanto o Híbrido de Timor UFV 443-03, a planta representante da geração F 1 e as plantas do RC R foram resistentes. As plantas F 2 , quando inoculadas com a raça II, apresentaram dois padrões de segregação signifi cativos: 15:1 e 61:3. A herança da resistência foi confi rmada pela inoculação das plantas do RC S , que segregaram na proporção de 3:1, padrão esperado para herança condicionada por dois genes. A hipótese de segregação 7:1 para três genes foi rejeitada. Resultados semelhantes foram obtidos para o patótipo 001. Dois genes dominantes e independentes conferem a resistência genética do Híbrido de Timor UFV 443-03 à raça II e ao patótipo 001 de H. vastatrix.Item Assessment of EST-SSR markers for genetic analysis on coffee(Instituto Agronômico (IAC), 2009-07) Missio, Robson Fernando; Caixeta, Eveline Teixeira; Zambolim, Eunize Maciel; Pena, Guilherme Ferreira; Ribeiro, Ana Paula; Zambolim, Laércio; Pereira, Antônio Alves; Sakiyama, Ney SussumuEST-SSR markers were used to investigate the genetic diversity among and within coffee populations, to explore the possibility of their use for fingerprinting of cultivars and to assist breeding programs. Seventeen markers, developed from ESTs (Expressed Sequence Tags) from the Brazilian Coffee Genome Project, were used. All markers showed polymorphism among the genotypes assessed. The average number of allele per primer was 5.1. The highest polymorphisms were found within C. canephora (88.2%) and rust-resistant varieties (35.3%). About 29.4% of the markers differentiated C. arabica from Híbrido de Timor; it was also possible to identify those closest and farthest from C. arabica . The analysis of population-grouped genotypes revealed a 64.0% genetic diversity among and a 36.0% genetic diversity within populations. The differentiation index was 0.637. Six markers distinguished four rust-resistance varieties, showing their fingerprinting potential. These results demonstrate the usefulness of EST-SSR markers for cross orientation, in diversity and introgression studies, and in genetic mapping.