Crop Breeding and Applied Biotechnology
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Item New and efficient AS-PCR molecular marker for selection of coffee resistant to coffee leaf rust(Crop Breeding and Applied Biotechnology, 2024-10-15) Almeida, Dênia Pires de; Carneiro, Deisy Guimarães; Caixeta, Eveline Teixeira; Alves, Danúbia Rodrigues; Zambolim, LaércioCoffee leaf rust, caused by Hemileia vastatrix, is the most important disease affecting Coffea arabica. The use of molecular markers through marker-assisted selection (MAS) is an effective approach to develop cultivars with multiple and durable resistance, which is economically and environmentally beneficial for this disease control. In this work, a new molecular marker based on allele-specific polymerase chain reaction (AS-PCR) associated with the quantitative trait locus (QTL) of the linkage group 5 (LG5), which confers resistance to races I, II and pathotype 001 of H. vastatrix, was developed. The CaRHv10-AS marker was validated in a segregating genetic mapping population of 247 F2 genotypes and demonstrated selection efficiency greater than 97% for genotypes with resistance to three races. Thus, this work provides a fast, robust, and affordable molecular marker for use in MAS, facilitating the development of coffee plants with multiple resistance and ensuring sustainable coffee production.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 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 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.