Periódicos
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
Navegar
21 resultados
Resultados da Pesquisa
Item Characterization and genetic diversity of Coffea canephora accessions in a germplasm bank in Espírito Santo, Brazil(Crop Breeding and Applied Biotechnology, 2021-06-20) Ferrão, Maria Amélia Gava; Mendonça, Rodolfo Ferreira de; Fonseca, Aymbiré Francisco Almeida; Ferrão, Romário Gava; Senra, João Felipe Brites; Volpi, Paulo Sérgio; Verdin Filho, Abraão Carlos; Comério, MarconeThe state of Espírito Santo is the major producer of Coffea canephora in Brazil. Knowledge of genetic reserves is fundamental to plant breeding. Therefore, the present study characterized and analyzed the genetic diversity of 600 C. canephora accessions from the germplasm bank of Incaper based on 38 traits evaluated in 24-30-month-old plants. Further, the predominant descriptors or traits were identified, and high phenotypic variability was determined. Genetic distances for the grouped (Gower), quantitative, and qualitative datasets were 0.48, 0.61, and 0.92, respectively, with accessions 76 (Conilon) and 407 (Robusta) being the most divergent ones at Incaper. In clustering using the Tocher optimization method, 30 groups were formed, with three accessions introduced from Epamig’s Robusta collection being the most dissimilar ones. Graphical dispersion analysis using the principal coordinate method revealed the predominance of three groups formed by the Robusta, Conilon, and hybrid Robusta × Conilon genotypes.Item Comparison of fructification efficiency between reciprocal crosses in Coffea canephora(Universidad Nacional de Colombia, 2023-10-09) Ferrão, Maria Amélia Gava; Fonseca, Aymbiré Francisco Almeida da; Ferrão, Romário Gava; Volpi, Paulo Sérgio; Verdin Filho, Abrão Carlos; Rocha, Rodrigo Barros; Riva-Souza, Elaine ManelliThis study aimed to assess and compare the behavior of superior genotypes of Coffea canephora in terms of fruiting capacity using directed hybridizations in a full diallel design with reciprocals.Hybridizations were performed using 12 possible combinations between genotypes 02, 03, 23 and 83 from the Incaper breeding program. High estimates of the genotypic coefficient of determination in terms of the total number of pinheads per cross (TNP) and fruit set (FS) indicated variability of genetic nature. FS averaged 52,27%, ranging from 31,32% to 82,09%, with the higher rates relating to clone 23 as the male parent. Differences were found between reciprocal crosses in the combinations with genotype 23, which emerged as the donor plant with the best fruiting rate, but poor receiving ability. Clone 83 prevailed as the best receiving plant and the least effective donor. In the comparison of these two genotypes, antagonism was observed in their behavior when they were used as pollen-donor plants (male parents) and pollen-receiver plants (female parents), highlighting their possible maternal effect. Crosses involving clones 02 and 03 showed no differences when used reciprocally. The estimates of genotypic correlations were negative for the four associations involving the FS characteristic, being of greater magnitude with TNP.Item Initial performance and genetic diversity of coffee trees cultivated under contrasting altitude conditions(Escola Superior de Agricultura "Luiz de Queiroz", 2023-08-14) Senra, João Felipe de Brites; Silva, Josimar Aleixo da; Ferreira, Adésio; Esposti, Marlon Dutra Degli; Ferrão, Maria Amélia Gava; Fassarella, Kamila Machado; Silva, Uliana Ribeiro; Milheiros, Idalina Sturião; Silva, Fernanda Gomes daThis work evaluated the initial performance and genetic diversity of Coffea canephora genotypes cultivated in environments at contrasting altitudes. Fourteen morphophysiological traits and seven descriptors of the genus Coffea spp. of coffee trees cultivated at altitudes of 140 m and 700 m were evaluated. The design used was Federer’s augmented block in a 2 × 112 factorial scheme with six blocks. The first factor was the two environments, and the second was the 112 genotypes, with eight common treatments, being five conilon coffee clones and three arabica coffee cultivars. The data were analyzed by the method of REML/BLUP and genetic correlation method. Genetic diversity was evaluated by estimating the distance matrix, applying the Gower methodology followed by the clustering method by Tocher and UPGMA. The phenotypic means were higher in the environment at an altitude of 700 m, except for plant height, number of leaves, and canopy height (CH). Genotypic effects were significant for most traits except for leaf width, CH, unit leaf area, and total leaf area. A wide genetic diversity was verified, with distances varying from 0.037 to 0.593 for the pairs of genotypes 26 × 93 and T7 × 76, respectively. Most of the traits studied showed high genotypic correlation with the environment and expressive genetic correlation between the evaluated traits thereby demonstrating the possibility of indirect selection. There is an adaptation of conilon coffee genotypes to high altitudes and the possibility of developing a specific cultivar for the southern state of Espírito Santo.Item Prediction of selection gains in Coffea canephora based on factorial scores(Crop Breeding and Applied Biotechnology, 2004) Ferreira, Adésio; Cecon, Paulo Roberto; Cruz, Cosme Damião; Ferrão, Romário Gava; Silva, Marcia Flores da; Fonseca, Aymbiré Francisco Almeida da; Ferrão, Maria Amélia GavaThe technique of factor analysis in the simultaneous selection of traits and prediction of genetic gains was evaluated in Coffea canephora var. conilon. Fourteen traits in 40 assessed genotypes were evaluated at two sites. The technique was used aiming at the structuring and simplification of the data, without information loss and with biological interpretation. The experimental design was of randomized blocks in four replications, each plot containing two useful plants. The technique was efficient for the data simplification and structuring. Moreover, the estimates of the predicted gains in the traits involved in the factors showed magnitude near the direct selection gain, attesting the suitability of the technique and its use in improvement programs of the species.Item Repeatability and number of harvests required for selection in robusta coffee(Crop Breeding and Applied Biotechnology, 2004) Fonseca, Aymbiré Francisco Almeida da; Sediyama, Tocio; Cruz, Cosme Damião; Sakiyama, Ney Sussumu; Ferrão, Romário Gava; Ferrão, Maria Amélia Gava; Bragança, Scheilla MarinaThis study aimed to estimate the repeatability coefficient of the grain yield in Coffea canephora by three methods: to quantify the precision of the measurements; to predict the real value of an individual based on n evaluations; and to determine the number of phenotypic measures required in each plant to obtain an adequate precision level for an efficient discrimination of the genotypes. The coefficients of repeatability and determination were estimated based on four harvests of 80 genotypes. Highest estimates of the repeatability coefficient were obtained by the method of the principal components derived from the matrix of covariances, which expresses the correlation between each measurement pair. The prediction precision of the real individual value ranged from 65.32 to 81.59%, and remained practically unchanged from the sixth harvest on.Item Inter-trait relations for direct and indirect selection in coffee(Crop Breeding and Applied Biotechnology, 2008-06-09) Ferrão, Romário Gava; Ferreira, Adésio; Cruz, Cosme Damião; Cecon, Paulo Roberto; Ferrão, Maria Amélia Gava; Fonseca, Aymbiré Francisco Almeida da; Carneiro, Pedro Crescêncio de Souza; Silva, Marcia Flores daThe purpose of this study was to verify the possibility of using direct selection in nine traits underlying indirect selection for yield and determine which traits should participate in the selection process. Data of 40 Conilon coffee genotypes were analyzed in two experiments in the growing seasons of 1996, 1998, 1999, 2000 and 2001 in random blocks with four and six replications. The significance of phenotypic associations was evaluated by the t test and the genotypic and environmental associations by bootstrap resampling. The genotypic associations were higher than the phenotypic, indicating a prevailing influence of the genotypic over the environmental effects in the relationship between significant traits; equal signs indicated a lack of contrary action among the effects. The traits related to cycle; yield; ratio of fresh ripe cherries to clean coffee; empty or flat grains; and sieve 17 should be maintained in the selection, evaluation and study of genetic divergence. The estimated gains in grain yield by indirect selection for any trait studied are not satisfactory.Item Discriminant analysis for the classification and clustering of robusta coffee genotypes(Crop Breeding and Applied Biotechnology, 2004-07-07) Fonseca, Aymbiré Francisco Almeida da; Sediyama, Tocio; Cruz, Cosme Damião; Sakiyama, Ney Sussumu; Ferrão, Romário Gava; Ferrão, Maria Amélia Gava; Bragança, Scheilla MarinaThis study evaluated the adequacy of the composition of three clonal Coffea canephora varieties recommended for the State of Espírito Santo by a multivariate method designated discriminant analysis. This method consists in the establishment of functions that enable the classification of a given individual into one, among various distinct populations, reducing the probability of a misclassification. It simultaneously considers measures of several traits, in order to give the new variety homogeneity. The original classification of genotypes in the three studied varieties, based on agronomical criteria, maintained expressive concordance with the results of the discriminant analysis, with an apparent deviation rate of only 6.25%. Corrected discriminant functions were also proposed, capable of classifying a new genotype into one of the three clonal varieties to be used in improvement programs, eliminating the subjectivity of the clustering process.Item Genetic divergence in Conilon coffee revealed by RAPD markers(Crop Breeding and Applied Biotechnology, 2009) Ferrão, Maria Amélia Gava; Fonseca, Aymbiré Francisco Almeida da; Ferrão, Romário Gava; Barbosa, Wellington Marota; Souza, Elaine Manelli RivaThis study aimed to evaluate the genetic variability of 49 Coffea canephora clones of the breeding program of the Capixaba Institute of Research, Technical Assistance and Rural Extension (Incaper) based on RAPD markers. Thirty-one primers were used with polymorphism patterns that generated 333 markers, of which 231 (69.4%) were polymorphic. The group of genotypes based on the UPGMA algorithm and Tocher optimization methods detected high divergence in the genotypes. It was found that the component clones of each clone variety recommended by Incaper are distributed in various genetically dissimilar groups, in spite of common phenotypic traits. The relatively wide genetic diversity observed here demonstrates the importance of hybridizations between these germplasms. The RAPD markers efficiently estimated the genetic divergence in the 49 C. canephora genotypes studied.Item Genetic variability of conilon coffee population from cultivar ‘ES8152’ based on morphoagronomic variables(Universidade Federal de Lavras, 2022-06-09) Senra, João Felipe de Brites; Silva, Josimar Aleixo da; Ferrão, Maria Amélia Gava; Esposti, Marlon Dutra Degli; Milheiros, Idalina Sturião; Fassarella, Kamila MachadoThis study aimed to analyze the genetic variability of Coffea canephora population with 190 genotypes from cultivar ‘ES8152’, based on morphoagronomic characteristics and vegetation index, to identify the most important characteristics for genetic divergence and compare them with commercial clones. The experiment was installed, in 2019, at the Bananal do Norte Experimental Farm/INCAPER, Cachoeiro de Itapemirim, ES, Brazil. The experiment was carried out in Federer’s augmented block design with three blocks, four common treatments (commercial clones A1, LB1, V8 and V12) and 190 regular treatments, genotypes from the seed production field of the conilon coffee cultivar ‘ES8152’. At 24 months of age 14 morphoagronomic characteristics and vegetation index were evaluated. Descriptive analysis of the data, the estimation of the Standardized Euclidean Distance (ED) followed by the group-ing by the methods of Tocher, UPGMA and principal coordinates, in addition to the relative importance of the characters estimated by the Singh meth-odology were performed. The most distant genotypes were 62 and 83 (ED=2.620) and the closest were 42 and 160 (ED=0.208). Genotype 83 stood out as the most distant among the others. The optimization and hierarchical groupings allowed the identification of genotypes 15, 81, 107 and 184 as similar to commercial clones. The discard analysis of variables recommended the elimination of the vegetation index and average internode length of the next diversity analysis. Principal coordinate analysis found phenotypic similarity of the genotypes 30, 81, 115, 141 and 163 with the clone V12, of the genotype 119 with the clone A1 and genotype 17 with clone LB1. The study, of morphoagronomic characters, allowed to detection the genetic diversity existing in the materials evaluated, indicating those with phenotypic similarity with the commercial clones, being possible the early identification of promising genotypes, agronomically superior, to start a breeding program for clonal selection, recurrent selection and controlled crosses to maximize heterosis.Item Genótipos de café conilon e sua reação à ferrugem alaranjada(Grupo Paulista de Fitopatologia, 2019) Mendonça, Rodolfo Ferreira de; Jesus Junior, Waldir Cintra de; Ferrão, Maria Amélia Gava; Moraes, Willian Bucker; Busato, Laedio Magno; Ferrão, Romário Gava; Tomaz, Marcelo Antonio; Fonseca, Aymbiré Francisco Almeida daO objetivo deste trabalho foi avaliar o comportamento de 54 clones de cafeeiro conilon oriundos do Programa de Melhoramento Genético do Incaper à ferrugem em condições controladas de temperatura e fotoperíodo. Utilizou-se o delineamento inteiramente casualizado com três repetições, sendo cada repetição composta por 16 discos de folha cada, acondicionados em gerbox e inoculados com 104 esporos.mL-1 de H. vastatrix. Os gerbox foram colocados sob ausência de luz e 22ºC por 48 horas e então em fotoperíodo de 12 horas até o término do experimento. Foram avaliados os componentes de resistência: período de incubação, período latente, incidência, porcentagem de discos com esporulação, número de esporos e severidade. Com base nos resultados verificou-se a formação de três grupos de genótipos de café conilon: Resistentes, Moderadamente Resistentes e Suscetíveis. No grupo Resistente foram alocados 19 genótipos, no grupo Moderadamente Resistente foram alocados 19 genótipos e no grupo Suscetível foram alocados 16 genótipos. Assim, com base nos resultados, conclui-se que há variação no nível de resistência dos genótipos de C. canephora à H. vastatrix. Tal informação subsidia os programas de melhoramento na seleção adequada de progênies de C. canephora quanto à resistência à ferrugem.
- «
- 1 (current)
- 2
- 3
- »