Biblioteca do Café
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Item Oxidative stability of biodiesel in the presence of leaves and fruit extracts(Universidade Federal do Ceará, 2025-05-09) Branco, Isadora Guilherme; Romagnoli, Erica Signori; Gonçales Filho, José; Mantovani, Ana Carolina Gomes; Borsato, DionisioThis research evaluated the efficiency of ethanolic extracts from yerba mate leaves (Ilex paraguariensis), coffee leaves (coffea arabica), and jambolan pulp (Syzygium cumini Lamarck) through the application of the simplex-centroid mixture design, the super modified simplex optimization algorithm, and the functions of desirability, using the induction period (IP) and the rate constant (k) of the biodiesel oxidation reaction at 110 °C as responses. Antioxidant activity was observed in all extracts, manifesting either by reducing the rate constant or extending the biodiesel induction period in comparison to the control sample. The mathematical models derived from the simplex-centroid design exhibited adjusted determination coefficients of 0.990 for the IP model and 0.960 for the k model. Analysis of variance indicated the significance of both models at the 5% significance level for IP and k, with p1 = 7.382 × 10−4 and p2 = 1.177 × 10−3, respectively. The lack of fit was not significant at the same level with p1 = 0.132 and p2 = 0.653, showing that they can be used for predictive purposes. The analysis of the response surface and optimization using the super modified simplex method revealed that higher proportions of coffee leaves extract in the mixture yielded superior IP values and lower k values.Item Arbuscular mycorrhizal fungal communities associated with coffee intercropped with grevillea(Sociedade Botânica do Brasil, 2024-12-02) Santos, Roberta de Souza; Miguel, Divino Levi; Freitas, Leandro Martins de; Assis, Fábia Giovana do Val de; Teixeira, Valber Dias; Kemmelmeier, Karl; Stürmer, Sidney Luiz; Leal, Patrícia LopesArbuscular mycorrhizal fungi (AMF) communities in coffee-cultivated areas in the northeastern region of Brazil have been insufficiently studied when compared to other Brazilian regions. This study determined AMF occurrence and richness in coffee-cultivated soils under different management systems in the State of Bahia, Brazil, and in soils from surrounding areas with pasture and native forest (control areas). Physicochemical soil characteristics in the different study areas were also evaluated. A total of 43 AMF spore morphotypes in 14 genera belonging to six families were recovered from soil samples from all study areas: Glomeraceae (35%), Acaulosporaceae (35%), Gigasporaceae (21%), Ambisporaceae (5%), Archaeosporaceae (2%) and Diversisporaceae (2%). Rhizophagus fasciculatus, Acaulospora mellea and Glomus sp. 1 were the most frequent fungi found in all areas. In the coffee-cultivated areas, 12 genera were identified, two of which (Dominikia and Fuscutata) had not yet been reported in association with coffee plants in Brazil. We concluded that soil physicochemical properties and AMF occurrence can distinguish study areas based on land use. The different coffee management systems did not influence AMF species richness, but the occurrence was influenced by both management and soil factors.Item From anthesis to harvest: evolution of the fructification of Conilon coffee genotypes grown at a transitional altitude(Instituto Agronômico (IAC), 2025-07-07) Colodetti, Tafarel Victor; Tomaz, Marcelo Antonio; Sartori, Lucas; Salles, Rodrigo Amaro de; Souza, Inês Viana de; Senra, João Felipe de Brites; Rodrigues, Wagner NunesBeginning with anthesis, this study aimed to evaluate the growth evolution of fruits of nine genotypes of Conilon coffee with an early cycle of maturation that were cultivated at a transitional altitude. The experiment was conducted in a competition field with Coffea canephora genotypes at a 647-m altitude, following a randomized block design with nine treatments, four replicates, and the genotypes making up the cultivar “Diamante ES8112” (101, 102, 103, 104, 105, 106, 107, 108, and 109). From the anthesis day, evaluations were made every 28 days, ending with the harvest, at which time the characteristics of growth and biomass accumulation of flowers and fruits of each genotype were evaluated. All analyzed characteristics of the flowers and fruits cultivated at a transitional altitude showed differentiation between the nine early-maturing Conilon genotypes. Altitude cultivation increased the duration of fruit development phases, averaging from 252 to 308 days among genotypes, from anthesis to harvest. Genotype 106 stood out for the fewest flowers and fruits per reproductive node and lowest fruit holding rates and dry biomass, whereas genotype 108 stood out for the most flowers and fruits per reproductive node, largest flower diameter, highest fruit holding rate, and greatest dry biomass.Item Relations between sensory quality and spectral indices in brazilian arabica coffees(Academia Brasileira de Ciências, 2025-03-17) SARMENTO, CARLA SIMONE A.G.; LEMOS, ODAIR L.; BOFFO, ELISANGELA F.; MATSUMOTO, SYLVANA N.; CASTRO, INGRID THALIA P. DE; ALVARENGA, YASMIN A.This article describes an investigation using spectral indices to characterize coffee production of Brazil, regarding beverage quality and possible correlations with the growing environment. The study evaluated 50 arabica coffee samples, 16 of which were natural process, and 34 were pulped coffes. These samples were originated from growing areas located in different altitude ranges and regions of the municipality, with similar planting spacing and predominance of Catuai cultivars. The samples were subjected to sensory analysis, which revealed that 58% of the samples were classified as specialty coffees: 3 natural, and 26 pulped coffes. Multiple correspondence analysis showed that average spectral indices, normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and photochemical reflectance index (PRI), derived from images of the multispectral instrument (MSI), were not associated with the quality parameters of the coffee beverage. In contrast, the plant senescence reflectance index (PSRI) proved to be the relevant factor in the quality of the drink. In summary, the analysis of the relationship between the indices demonstrated that the NDVI, which measures the vegetative vigor of plants, showed an inverse correlation with the PSRI. Additionally, the principal component analysis suggested that samples collected from drier areas differed significantly from other geographic regions.Item Temporal analysis of Phoma leaf spot of coffee plants at different altitudes(Universidade Federal de Viçosa, 2025-04-25) Silva, Humberson Rocha; Pozza, Edson Ampélio; Freitas, Aurivan Soares de; Freitas, Marcelo Loran de Oliveira; Barbosa Junior, Mauro Peraro; Cirillo, Marcelo AngeloPhoma leaf spot (Phoma spp.) of coffee causes losses of between 15 and 43%, and presents significant variability over time and space, especially in mountain coffee production. Thus, the objective of this study was to evaluate the behavior of this disease at different altitudes and to use time series techniques and regression models to explain disease behavior. The experiment was conducted over two years (from September 2013 to August 2015) with monthly evaluations in a Coffea arabica L. plantation. The incidence and severity progress curves showed irregular behavior most of the time, typical of the disease. Higher altitudes provided higher disease incidence and severity values. Only the incidence and severity progress curves at the altitude of 1143.2 m showed significant autocorrelation over time. Thus, the first-order autocorrelation structure, AR(1), was incorporated in the estimates of the parameters of the linear and nonlinear models. Only the months from February to June/July 2014 were considered, when the disease progressed regularly. The rates obtained for the incidence, overall mean of the 85 points and mean altitude of 1143.2 m, were 5.2 and 4.6%, respectively, while the estimated rates for the severity data under the same conditions were 0.3 and 0.1%, respectively. These values represent the expected increase in incidence and severity each month. The Phoma leaf spot presents complex temporal dynamics, influenced by microclimatic variables associated with altitude.Item An interdisciplinary approach for evaluating beverage quality in Coffea canephora(Academia Brasileira de Ciências, 2025-05-09) SOUZA, LUCIMARA C. DE; FERRÃO, MARIA AMÉLIA G.; FONSECA, AYMBIRÉ FRANCISCO A. DA; VOLPI, PAULO SÉRGIO; COMERIO, MARCONE; PEREIRA, LUCAS L.; CARVALHO, JOSÉ AUGUSTO M.; SARAIVA, SÉRGIO H.; PINHEIRO, PATRÍCIA F.; SILVA JÚNIOR, ADELSON L. DA; SOARES, TAÍS CRISTINA B.The objective of this study was to assess the quality of Conilon coffee (Coffea canephora) based on agronomic, physicochemical, sensory profiles, and molecular markers. The dataset comprises 107 genotypes from the Incaper breeding program, evaluated in Marilândia, ES, Brazil. A total of 30 traits and 14 SSR markers were examined, revealing significant genetic variability. Most genotypes exhibited a medium June harvest cycle, uniform ripening, medium-sized beans, high processing yield, and a high percentage of flat and peaberry beans. Physicochemical variables, total titratable acidity, and potassium leaching contributed significantly to the observed variability. Chlorogenic acids (4.82%) and caffeine (2.58%) were the most abundant bioactive compounds. In sensory evaluations, 34 genotypes received scores exceeding 80. 13 markers were recommended for future association mapping studies to identify QTLs influencing the traits evaluated. Results identified genotypes with potential to maximize heterosis and genetic diversity in advancing generations. Among the evaluated genotypes, 34 were identified as promising due to their high sensory scores (≥ 80 points) and favorable agronomic, physicochemical, sensory, and genetic traits. The progeny HS17 stood out as the most divergent in agronomic and genetic traits compared to the other genotypes.Item Spray deposition from an unmanned aerial vehicle on a coffee crop(Associação Brasileira de Engenharia Agrícola, 2024-11-29) Cunha, João P. A. R. da; Fonseca, Luciano F. da; Alvarenga, Cleyton B. de; Lopes, Luana de L.; Martins Filho, Rogério M. S.The use of unmanned aerial vehicles (UAVs) to apply pesticides has grown significantly, but technical data to support improvements in application efficiency are lacking, especially for perennial crops. This study aimed to determine the best operational parameters for the application of pesticides to coffee plants using UAVs. The experiment consisted of 8 treatments and 4 replicates in a 2x2x2 factorial design: two spray mixture compositions (solutions with spreading adjuvant and mineral oil), two spray nozzles (XR flat-fan nozzle and Airmix flat-fan nozzle with air induction) and two spray volumes (10 and 20 L ha-1). Spray solution deposition was evaluated by spectrophotometric detection of a tracer in leaves from the upper and lower parts of the coffee canopy, and spray coverage, droplet density and droplet size were evaluated using water-sensitive paper. The surface tension, pH and electrical conductivity of the solutions were also evaluated. The air induction nozzle was more suitable than the standard nozzle for UAV application, as the former yielded greater deposition of spray solution. Mineral oil improved the spray deposition on the coffee leaves, although the spreader reduced the surface tension to a greater extent. The higher spray volume increased the droplet density, as well as the coverage, which is very relevant, especially whit contact pesticides.Item Fruit and bean traits of the Coffea canephora genotypes most grown in western Amazon(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2024-11-25) Lopes Júnior, Hilton; Rocha, Rodrigo Barros; Silva, Adriele Nunes Rodrigues; Moraes, Amanda de Oliveira; Alves, Enrique Anastácio; Espindula, Marcelo Curitiba; Teixeira, Alexsandro LaraThe objective of this work was to quantify the genetic diversity and selection gains regarding the physical traits of the fruits and beans of the 86 Coffea canephora clones most grown in western Amazon. The clones were evaluated as to the effects of genotypes (G), years (Y), and the GxY interaction. Genetic progress was quantified considering combined selection and direct selection for coffee bean weight. Although there was a GxY interaction, based on repeatability estimates the plants presented a similar performance over time. A positive correlation was observed between fruit and bean weight, except for some genotypes, such as R22, AS5, and 'BRS 3210', which presented larger beans and smaller fruit, and as BG180, P42, LB60, G20, and N12, with larger fruit and smaller beans. Using selection for the main trait, the estimates of genetic progress were similar to those obtained through different selection indexes, through which 14 genotypes with a higher bean weight were selected. The evaluated C. canephora clones exhibit high genetic diversity for the selection of plants with higher grain mass.Item Leaf area estimation in Coffea canephora genotypes by neural networks and multiple regression(Departamento de Engenharia Agrícola - UFCG, 2024-07-19) Vitória, Edney L. da; Nardotto Júnior, André O.; Ribeiro, Luis F. O.; Dubberstein, Danielly; Partelli, Fábio L.Leaf area data from coffee plants are important for studies and analyses of grain yield, physiology, adaptation to environmental conditions, and cultural management. The objective of this study was to predict leaf area of coffee plants using artificial neural networks and compare the efficiency of this methodology with multiple regression models. Forty-three genotypes of similar reproduction and age were evaluated, testing 14 types of multiple regression equations from combinations of leaf length and width. The backpropagation algorithm was used to develop multilayer perceptron neural networks; several combinations were tested between two activation functions of the intermediate layer (hidden layer) and the number of neurons in this layer. The best fitting results in the artificial neural network modeling were found with the sigmoid activation function and three neurons in the hidden layer (R² = 0.990 and RMSE = 2.855 in the training phase). Considering the errors (RMSE, MAE, and MAPE) and the coefficient of determination as criteria for best fit, the artificial neural network models better estimated the leaf area in the training and validation phases. Therefore, the artificial neural network methodology can be used as alternative for estimating leaf area of coffee plants.Item Caffeine levels in leaves of Palicourea marcgravii and Palicourea hoffmannseggiana (Rubiaceae)(Universidade Federal de Minas Gerais, Escola de Veterinária, 2025-01-27) Teixeira, C.J.R.; Saraiva, C.J.C.; Soto-Blanco, B.A presença de cafeína nas folhas de Palicourea marcgravii foi relatada anteriormente, e esperava-se que a determinação desse composto em amostras animais servisse como marcador do consumo da planta. Porém, os níveis de cafeína presentes nas folhas de Palicourea são desconhecidos. Portanto, o presente estudo teve como objetivo determinar os teores de cafeína em folhas de Palicourea marcgravii e P. hoffmannseggiana. Foram coletadas folhas jovens de 10 exemplares de P. marcgravii e 10 exemplares de P. hoffmannseggiana. Além disso, as folhas jovens de dois cafeeiros (Coffea arabica) foram utilizadas como controle positivo para cafeína. Essas amostras foram submetidas à medição de cafeína por cromatografia líquida de alta eficiência (CLAE). Os níveis de cafeína encontrados nas folhas de café foram de 6,4 e 7,7mg/g, mas a cafeína não foi detectada em todas as amostras avaliadas de folhas de P. marcgravii e P. hoffmannseggiana. Como o limite de detecção do método analítico utilizado é de 0,15μg/mL, os níveis de cafeína nas folhas das duas espécies de Palicourea são insignificantes (inferiores a 3,0μg/mg), se essa substância realmente estiver presente. A ausência de cafeína nas folhas de Palicourea avaliadas neste estudo impossibilita a utilização dessa substância como marcador do consumo dessas plantas.