Biblioteca do Café

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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 Manelli
This 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.
In vitro pollination and fluorescence microscopy for characterization of gametophytic selfincompatibility of Coffea canephora Pierre ex A. Froehner
(Crop Breeding and Applied Biotechnology, 2021-11-20) Souza, Carolina Augusto de; Rocha, Rodrigo Barros; Santos, Maurício Reginaldo Alves dos; Lopes, Tatiane Almeida; Teixeira, Alexsandro Lara; Espindula, Marcelo Curitiba
The objectives of this study were to optimize in vitro pollination and fluorescence microscopy procedures to characterize the gametophytic selfincompatibility of Coffea canephora genotypes. For that purpose, 115 in vitro pollinations were carried out among 30 parent plants of the Conilon (17) and Robusta (13) botanical varieties. Tester plants of compatibility groups I, II, and III were used as pollen grain donors. On the day of anthesis, pollen grains of the donor genotypes were transferred in vitro to one of the sides of the bifid stigma of each receptor flower. After 30 hours, the development of the pollen tubes was evaluated in fluorescence microscopy. Eleven genotypes (37%) were classified in compatibility Group I, thirteen (43%) in Group II, and six (20%) in Group III. In vitro pollination allowed reduction in the time necessary to diagnose compatibility, without exhibiting contamination caused by the presence of pollen grains of non-donor plants.
Expression of self-incompatibility in Coffea canephora genotypes grown in the western Amazon
(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2022-12-05) Depolo, Rodrigo Prado; Rocha, Rodrigo Barros; Souza, Carolina Augusto de; Santos, Maurício Reginaldo Alves dos; Espindula, Marcelo Curitiba; Teixeira, Alexsandro Lara
The objective of this work was to characterize the expression of gametophytic self-incompatibility in a Coffea canephora breeding population, to assist in the management and development of new cultivars. For that purpose, 550 in vitro pollinations were carried out among 62 parent plants, of which 27 were from the conilon botanical variety and 35 from the robusta. Thirty-two genotypes compatible with all previously known testers were identified, suggesting the existence of new compatibility groups. From these results, hybridizations were carried out in a complete diallel design with reciprocal crosses to characterize new test plants. Based on the compatibility response with the test plants, the genotypes were clustered into the six following groups: group I, 11 (17.74%) genotypes; group II, 13 (20.97%); group III, 6 (9.68%); group IV, 9 (14.52%); group V, 8 (12.90%); and group VI, 15 (24.19%). The genotypes of the botanical variety robusta show a higher frequency of plants in compatibility group VI and a greater genetic variability, whereas those of the conilon variety have a higher frequency of plants in compatibility group II. The identification of new compatibility groups assists in new management practices that seek to increase the efficiency of pollination by favoring, through natural means, fully compatible crosses.
Factor analysis for plant and production variables in Coffea canephorain the Western Amazon
(Universidade Federal de Lavras, 2022-06-09) Silva, Gabi Nunes; Barroso, Laís Mayara Azevedo; Cruz, Cosme Damião; Rocha, Rodrigo Barros; Ferreira, Fábio Medeiros
The evaluation of morphological characters related to the hulled coffee yield subsidizes the selection of Coffea canephora plants that combine a set of favorable traits. However, the greater the number of traits considered, the more difficult the selection process becomes. In this context, multivariate analyzes can be useful to overcome this problem. The aim of this study was to identify, in a set of agronomic traits of Coffea canephora, the determining factors of biological phenomena and use these factors to recognize patterns of diversity and similarity from biological complexes of interest to the breeder. To this, eleven morphological descriptors were evaluated of 130 clones of the botanical varieties Conilon and Robusta and intervarietal hybrids over two crop years in the experimental field of Embrapa, in the municipality of Ouro Preto do Oeste, state of Rondônia (RO). To group the traits, the multivariate technique of Factor Analysis was used. The effect of genotype x year interaction was significant for the eleven traits analyzed. Based on the scree plot, three factors were established. Factors were interpreted as architecture, vigor and grains with a satisfactory percentage of explained variability. The inter-pretation of the factors highlighted the importance of the Conilon variety to improve the architecture of the Robusta botanical variety. These results show that it is possible to use factor scores to identify varieties and traits that favor higher production of hulled coffee.
Classification of Coffea canephora clones in botanical varieties by discriminant analysis of the k-nearest neighbors
(Universidade Federal de Viçosa, 2021-11-08) Souza, Marciléia Santos; Ferreira, Fábio Medeiros; Rocha, Rodrigo Barros; Lopes, Maria Teresa Gomes; Oliveira, Leilane Nicolino Lamarão
A strategy for genetic improvement of coffee Coffea canephora plants is to aggregate through artificial crossings the characteristics of the Conilon botanical variety, such as shorter height and drought resistance, with the higher average grain size and resistance to pests and diseases of the Robusta variety. Efficiently separating the clones into these two groups with the aid of appropriate analytical procedures makes field tasks easier for professionals and, thus, allows the systematic production of intervarietal hybrids. This study verifies if the non-parametric discriminant analyzes of the k-nearest neighbors (k-NN) and k-average neighbors (k-AN) would be able to correctly classify 130 coffee clones in their botanical varieties previously designated as Conilon, Robusta and Intervarietal Hybrids populations from ten quantitative agronomic characteristics, including the processed coffee beans yield, considering the existing population genetic divergence. These characteristics were found to be good discriminatory variables and the discriminant analyzes k-NN and k-AN, based on the principle of similarity by neighborhood, classified the clones with high hit rates. The k-AN discriminant analysis was able to better discriminate intervarietal hybrids from the group clones Conilon. The results correctly reflected the genetic diversity between the botanical varieties and intervarietal hybrids of Coffea canephora, allowing us to conclude that these classification methods can assist breeders in the main task of discriminating Conilon from Robusta clones.
Environmental stratification and performance of Coffea canephora clones grown in the Western Amazon
(Editora UFLA, 2021) Moraes, Marcos Santana; Rocha, Rodrigo Barros; Ferreira, Fábio Medeiros; Souza, Carolina Augusto de; Espindula, Marcelo Curitiba; Teixeira, Alexsandro Lara
Change in the performance of clones grown in different environments is an important question for Coffea canephora breeding. The aim of this study was to evaluate environmental stratification and the performance of C. canephora clones grown in the Western Amazon. For that purpose, the mean yield of three crop seasons was considered to evaluate the performance of 20 genotypes grown in 6 clonal competition trials in the environments of: E1: Ouro Preto do Oeste-RO, E2: Porto Velho-RO, E3: Ariquemes-RO, E4 and E5: Rio Branco-AC and E6: Alta Floresta do Oeste-RO. The trials were conducted with a plant spacing of 3 m × 1.5 m in a complete block experimental design, with three replications of eight plants per plot. Combined analysis indicated significance of the genotype × environment (G×E) interaction and favorable conditions to obtain gains from selection. Reduction in the dimensionality estimated from climate and soil characteristics indicated that the environments of Porto Velho-RO, Rio Branco-AC and Ariquemes-RO are more similar to each other than the environments of Ouro Preto do Oeste-RO and Alta Floresta-RO of greater natural soil fertility and higher altitude. The AMMI1 biplot shows that genotypes 16, 10, and 13 had the highest mean yields, together with greater stability. In the AMMI2 scatterplot (IPCA1×IPCA2), the environ ments E4 and E5 were clustered in the same sector. Clustering based on the complex fraction of the G×E interaction coincided with the AMMI2 scatterplot that clustered the E4 and E5 environments in a single mega-environment. Except for these environments, all the others clustered as locations of different biotic and abiotic stress conditions. This result shows the importance of maintaining evaluations in these environments, which represent the conditions of the coffee fields in the region.
Amazonian Robustas - new Coffea canephora coffee cultivars for the Western Brazilian Amazon
(Crop Breeding and Applied Biotechnology, 2020) Teixeira, Alexsandro Lara; Rocha, Rodrigo Barros; Espindula, Marcelo Curitiba; Ramalho, André Rostand; Vieira Júnior, José Roberto; Alves, Enrique Anastácio; Lunz, Aureny Maria Pereira; Souza, Flávio de França; Costa, José Nilton Medeiros; Fernandes, Cleberson de Freitas
Amazonian Robustas are ten new clones of high yield potential with characteristics typical of the botanical varieties conilon and robusta. With individual registration, the new cultivars were developed to be grown together with other clones, with flexibility of composition of the crops according to the preference of the producer.
Coffea canephora breeding: estimated and achieved gains from selection in the Western Amazon, Brazil
(Universidade Federal de Santa Maria, 2021) Rocha, Rodrigo Barros; Teixeira, Alexsandro Lara; Ramalho, Andre Rostand; Espindula, Marcelo Curitiba; Lunz, Aureny Maria Pereira; Souza, Flavio de França
Gain from selection is an important criterion in quantifying the efficiency of breeding programs. This study quantified the selection gain estimated under experimental conditions and realized gain achieved in the field, seeking to interpret the efficiency of the Coffea canephora selection. For that purpose, we considered experiments that began in 2004 with directed hybridizations to obtain new hybrid progenies. From a breeding population composed of 288 hybrid individuals, 12 genotypes were selected in experimental conditions from 2005 to 2012, with amplitude in the estimated gains from 127.70 to−19.19%. Those genotypes were evaluated from 2012 to 2018 in clonal tests in four environments of the Western Amazon. The environment that exhibited the greatest correlation between the predicted genetic values and the realized genetic gain observed in the field was the environment of Ouro Preto do Oeste, RO (0.67), the location in which the plants were selected, followed by the environments of Alta FlorestaD´Oeste, RO (0.44), Rio Branco, AC (0.43), and Porto Velho, RO (0.37). Experimental conditions showed that the effect due to dominance deviations was approximately three times greater than the additive effect. Nine clones exhibited higher genetic gains in the experimental conditions and at field, and two clones exhibited lower estimated gains and lower field performance.The clone G17-P7 exhibited high genetic gain under experimental conditions and low field performance. The selection in experimental conditions was positively correlated with plant performance in the field (r=0.55), which allows reduction of the original breeding population to a set of more promising clones to be grown in multiple environments, optimizing time and resources.
Adaptability and stability of Coffea canephora Pierre ex Froehner genotypes in the Western Amazon
(Universidade Federal de Santa Maria, 2020) Moraes, Marcos Santana; Rocha, Rodrigo Barros; Teixeira, Alexsandro Lara; Espindula, Marcelo Curitiba; Silva, Camila Andrade; Lunz, Aureny Maria Pereira
The development of Coffea canephora cultivars is based on the characterization of genotype × environment interaction, which is interpreted to quantify the differential behavior of clones at different cultivation sites. The objective of this research was to study the genotype x environment interaction aiming to select clones of broad and specific adaptation to different environments of the Western Amazon. Twelve clones with hybrid characteristics of the botanical varieties Conilon and Robusta and four open pollinated clones, had their performance evaluated in comparison with four controls. The genotype × environment interaction was interpreted based on the environmental quality index, the nonparametric estimator of Lin and Binns, 1988 and on the dispersion of the centroid method. Effects of the genotypes, environment, and genotype × environment interaction were all significant (p<0.01). The environmental quality index (Ij) classified three environments as favorable for coffee production. In terms of the Lin and Binn’s estimator (Pi), hybrid genotypes 16, 10, 13, 09 and 14 presented lower Pi indices than others, and were classified as being more stable. Five clones of low adaptability, seven clones of specific adaptability to favorable or unfavorable environments and two clones of broad adaptability to all environments were identified interpreting the dispersion of the centroid method.
Beverage quality of Coffea canephora genotypes in the western Amazon, Brazil
(Editora da Universidade Estadual de Maringá - EDUEM, 2021) Morais, Johnnescley Anes de; Rocha, Rodrigo Barros; Alves, Enrique Anastácio; Espindula, Marcelo Curitiba; Teixeira, Alexsandro Lara; Souza, Carolina Augusto de
This study aimed to evaluate the beverage quality of Coffea canephora genotypes in different environments of the western Amazon to assist plant selection and new cultivar development. To analyze beverage quality, samples of cherry coffee beans were collected separately for each genotype from clonal competition trials installed in the municipalities of Ouro Preto do Oeste, Alta Floresta do Oeste, Porto Velho, and Ariquemes in Rondônia State and Rio Branco in Acre State (Brazil). The beverage quality was assessed using the Robusta Cupping Protocol, which attribute to each genotype a score in a range from 0 to 100, highlighting nuances. Analysis of variance and principal components using reference points were used to quantify genotype x environment interaction (G x E). The analysis of variance indicated that genotypic and G x E interaction effects were significant (p < 0.01). By using a centroid dispersion method, we could identify four clones of low, eight of specific (to favorable or unfavorable environments), and seven of broad adaptability to the environments. The clones BRS 2314, 11, and 17 had average quality scores above 80 in all environments, with potential for specialty coffee production. The clones BRS 1216, BRS 3220, and BRS 3193 presented unstable behavior, with beans of higher quality in some of the evaluated environments. Such inconsistency in clone behavior is caused by unpredictable changes in plant performance in different environments. Our results indicate that both genotypic (clones) and G x E interaction effects are important for the expression of coffee beverage quality. However, the clones BRS 3213, BRS 3210, and BRS 2299 had less prominent nuances, with lower potential for specialty coffee production.

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