Biblioteca do Café

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Caracterização de germoplasma de Coffea arabica L. com base em características agronômicas
(Universidade Federal Rural de Pernambuco, 2024-10-01) Silva, Maria Gabriela Pereira e; Abrahão, Juliana Costa de Rezende; Nadaleti, Denis Henrique Silva; Pereira, Antônio Alves; Fassio, Larissa de Oliveira; Botelho, Cesar Elias
Genetic resources embody the reservoir of essential natural variability for cultivated species breeding programs. The objective of this study was to select Arabica coffee accessions from the Minas Gerais Coffee Germplasm Collection grounded in agronomic traits. The productivity, quantified in bags per hectare, of 25 accessions was evaluated across four harvests, as was the percentage of maturation and floating beans. Genetic parameters were estimated for these attributes, aiming to glean insights into the potential for genetic gain and to facilitate decision-making in breeding practices. The REML/BLUP procedure was used to estimate variance components and predict random effects within the agronomic data. Genetic variability was observed among the studied accessions for productivity and the percentage of dried/pass fruits, indicating potential for genetic gain through selection within this group of accessions. There is potential for genetic breeding through selection, leading to subsequent enhancement in the means of the evaluated traits, notably in accessions MG0223 (Pacamara), MG0438 (Mundo Novo x S795 UFV 335-04), MG0194 (Caturra Amarelo Colombiano), MG0420 (Mundo Novo x S795 UFV 315-04), and MG0036 (Bourbon Amarelo). These results highlight the potential of these accessions to produce specialty coffees and their suitability for future breeding programs aimed at improving beans quality and productivity in Brazil.
Fenologia do cafeeiro: condições agrometeorológicas e balanço hídrico do ano agrícola 2003-2004
(Embrapa Café, 2007-07) Meireles, Elza Jacqueline Leite; Camargo, Marcelo Bento Paes de; Pezzopane, José Ricardo Macedo; Thomaziello, Roberto Antônio; Fahl, Joel Irineu; Bardin, Ludmila
Desenvolvimento vegetativo de cafeeiros cultivados sob estresses térmico e hídrico
(Universidade Federal de Viçosa, 2024-02-23) Carvalho, Maria Antônia Santos de; Pedrosa, Adriene Woods; Ferreira, Williams Pinto Marques; Ribeiro, Marcelo de Freitas; Picoli, Edgard Augusto de Toledo
O recente relatório do Intergovernmental Panel on Climate Change (IPCC) destacou os riscos iminentes do aumento da temperatura global. As alterações causadas por esse fenômeno têm efeito na ocorrência e distribuição de chuvas, o que poderá afetar diretamente os campos de produção agrícola. Em especial, tem-se a espécie Coffea arabica L., que apresenta aptidão agrícola para regiões com temperaturas médias amenas e necessidade de adequada disponibilidade hídrica, podendo, assim, perder locais de produção, que atualmente são aptos. Dessa forma, o objetivo deste trabalho foi avaliar o crescimento vegetativo e estado nutricional de três cultivares de C. arabica, submetidas aos estresses hídrico e térmico (baseado nos cenários do IPCC) em ambiente protegido, sendo elas, MGS Paraíso 2, Catucaiam 24137 e Catucaí Amarelo 2SL, com a finalidade de reunir informações sobre seus desempenhos diante das mudanças climáticas. Para isso, duas condições de temperatura foram consideradas: estufa ambiente (temperatura mais próxima do ambiente natural externo) e estufa ambiente + 3 °C (3 °C a mais que a estufa ambiente). Em cada estufa foi instalado um experimento em delineamento de blocos casualizados, em esquema de parcelas subdivididas 3 x 2, com as três cultivares mencionadas e dois níveis de estresse hídrico (com e sem estresse). Os resultados mostraram que o crescimento das cultivares foi prejudicado pelo estresse hídrico, com redução da altura da planta, diâmetro do caule, número de nós do ramo ortotrópico, número de nós nos ramos plagiotrópicos e número de ramos plagiotrópicos, índice SPAD, área foliar e produção de matéria seca. Os resultados também evidenciaram que o aumento da temperatura pode intensificar o efeito do estresse hídrico. Além disso, o estresse térmico também contribuiu com redução do crescimento radicular e do índice SPAD. Destaca-se que, em resposta aos dois estresses, ocorreu um aumento da concentração foliar de N e redução foliar de Ca e de micronutrientes como, B, Fe e Mn em resposta ao estresse hídrico. A concentração foliar do K permaneceu inalterada. Palavras-chave: Coffea arabica L.; Cultivares; Estresse abiótico; Crescimento vegetal; Estado nutricional.
Inhibition of respiration by light in Coffea arabica
(Universidade Federal de Lavras, 2023-12-29) Oliveira, Indira Pereira de; Barbosa, João Paulo Rodrigues Alves Delfino; Saleska, Scott; Pennacchi, João Paulo; Prohaska, Neill
Describing gas exchange between plants and the atmosphere is essential to improve current estimates of fluxes and carbon stocks. Light is directly related to gas exchange; when plants are under low light intensities, there is an increase in photosynthetic quantum yield and, consequently, in respiratory rate. That means there is an apparent inhibition of respiration under high light intensity, a phenomenon known as the Kok effect. Considering the effect of light and leaf age, the aim of this study was to describe the physiological responses of daytime gas exchange related to leaves of different ages in Coffea arabica L. cv. Catuaí Vermelho, seeking to identify leaf respiration inhibition by light. The experiment was conducted at the Universidade Federal de Lavras, Minas Gerais, Brazil. Leaves were measured using an infrared gas analyzer (IRGA; LI- 6400XT, LI-COR, Lincoln, NE, USA) and the fluxes were measured to create a light response curve in “in situ”, thus obtaining photosynthetic parameters, used to estimate light and dark respiration, also the rate of inhibition of leaf respiration by light throughout the leaf age. The assimilation (A_sat) and quantum efficiency did not differ among young, mature, and old leaves, showing that photosynthetic process was not affected by leaf age; however, light and dark respiration were higher in young and mature leaves than in old leaves. Inhibition of respiration by light was similar among leaf ages, assuming the occurrence of inhibition of respiration caused by light (the Kok effect).
Caffeine and chlorogenic acid content of Coffea canephora cultivars in different environments
(Universidade Federal de Lavras, 2023-11-19) Rocha, Rodrigo Barros; Alves, Enrique Anastacio; Tadeu, Hugo Cesar; Teixeira, Alexsandro Lara; Bizzo, Humberto Ribeiro; Antoniassi, Rosemar; Pacheco, Sidney; Santiago, Manuela Cristina Pessanha de Araujo
Coffee plants of the Coffea canephora species are currently grown in tropical regions throughout the world, and both greater yield efficiency and greater beverage quality are important considerations. The aim of this study is to characterize the content of caffeine and of chlorogenic acids of C. canephora cultivars in different environments. According to the maturation cycle of each clone, samples of cherry coffee were collected from ten cultivars evaluated in the environments of Porto Velho, RO, Ouro Preto do Oeste, RO and Manaus, AM. These environments with contrasting characteristics represent most of the coffee fields established in the Am and Aw climate types in Latossolos Vermelhos and Latossolos Amarelos, typical of the Western Amazon. The results were analyzed considering the factorial design to quantify the effects of genotypes, of environments, and of the genotype × environment interaction (GE) on the caffeine and chlorogenic acid contents. Regardless the significant GE effects, the caffeine and chlorogenic acid content exhibited predominantly genetic control. In comparison to the caffeine, the chlorogenic acid content was more affected by the environment effects, displaying more variations in the genotypes performance across the environments. The significant positive association between the caffeine and chlorogenic acid contents favors the selection of plants that simultaneously have greater or lower contents of both traits. The selection of clone BRS3210 resulted in a selection gain of 14.99% in caffeine content, while the cultivation of the clone BRS3193 yielded a selection gain of 10.81% in chlorogenic acid content. The selection of clone BRS2299 resulted in a reduction of 21.85% in caffeine content and of 9.15% in chlorogenic acid content.
Phosphorus fixation and its relationship with soils chemical properties of the coffee zone of Huila, Colombia
(Universidade Federal de Lavras, 2023-11-01) Poveda, Vanessa Catalina Díaz; Sadeghian, Siavosh
Adsorption is one of the critical processes in phosphorus (P) availability in plants. In the coffee crop (Coffea arabica), the highest dose of P is supplied in the vegetative phase, so its management is fundamental to guarantee the optimum growth of plants. The aim of this work was to determine the P fixation capacity and its relationship with the soil chemical properties of the Huila coffee zone, Colombian department, with the largest area planted with coffee. The adsorption isotherms were obtained by equilibrating the soil with 30mL of KH2PO4 solution dissolved in a 0.01M CaCl2.2H2O, containing concentrations of P between 50 and 4.200 mg kg-1. The P adsorption was measured for 60 soil samples collected from the five main cartographic units of the department: Campoalegre, El Recreo, La Cristalina, Saladoblanco, and San Simón. The data fitted to the linear and nonlinear Langmuir model forms. It was found that the soils of the region have a variable P fixation capacity, with values of q (adsorption at 0.2 mg L-1 in solution) between 8 and 1330 mg kg-1 and b (maximum adsorption capacity) from 117 to 3916 mg kg-1, without finding an association with the evaluated soil units. A correlation of q and b was found between Al3+, Al3+ saturation, pH, Ca2+ and Mg2+, and base saturation.
Productivity and physical quality of grains from Coffea arabica L. in a tropical high-altitude climate in Brazil
(Universidade Federal de Lavras, 2023-11-19) Martins, Adriana Novais; Turco, Patricia Helena Nogueira; Araújo, Humberto Sampaio de; Firetti, Ricardo
The coffee plant is extremely important for Brazilian agribusiness as it generates foreign exchange earnings and employment throughout the production chain. In this study, we evaluated the production and parameters related to the quality of 18 Coffea arabica L. cultivars grafted onto the Apoatã IAC 2258 cultivar, in seven consecutive harvests. The experiment was installed in 2014 and carried out for seven harvests, in Fazenda Recreio in the municipality of Vera Cruz, state of São Paulo, Brazil. We used a randomised block design (DBC), with three experimental replications, which were conducted in 54 plots. We analysed productivity, yield, and grain size parameters. The data were evaluated by the analysis of variance (ANOVA) and the mean values were used to conduct the Scott-Knott and Tukey test. The results showed that in all the cycles, the characteristics evaluated showed significant differences among the cultivars. The ratio between the residual mean squares of the analysis of variance was less than 7:1 for all the characteristics evaluated, which allowed us to compare the seven harvests with each other. The cultivars IPR 100, Obatã IAC 1669–20, IPR 107 and IAC 125 RN performed the best, as determined by the parameters evaluated, and thus, we recommend these cultivars for growing coffee tropical high-altitude climate in Brazil.
Influência da alta concentração atmosférica de CO2 (↑[CO2 ]atm) × disponibilidade hídrica nas relações hídricas, trocas gasosas e acúmulo de carboidratos em Coffea arabica L.
(Instituto de Pesquisas Ambientais, 2017) Sanches, Rodrigo Fazani Esteves; Catarino, Ingrid Cristina Araujo; Braga, Marcia Regina; Silva, Emerson Alves da
(Influência da alta concentração atmosférica de CO2 (↑[CO2]atm) × disponibilidade hídrica nas relações hídricas, trocas gasosas e acúmulo de carboidratos em Coffea arabica L.). O objetivo deste trabalho foi avaliar a influência da ↑[CO2]atm nas relações hídricas, trocas gasosas e acúmulo de carboidratos em Coffea arabica. Cafeeiros foram cultivados sob diferentes [CO2]atm (400 e 760 ppm) e submetidos a dois regimes hídricos: rega diária e ciclos de suspensão de regas por 7, 10, 14 e 37 dias, seguidos de reidratação diária por 7 dias. Alterações significativas no potencial hídrico foram observadas nas plantas sob restrição hídrica a partir do 10º dia com recuperação total após a reidratação. As A foram maiores nos cafeeiros cultivados sob ↑[CO2]atm, mesmo sob restrição hídrica se comparadas aos demais tratamentos. Cafeeiros cultivados em ↑[CO2]atm e restrição hídrica não apresentaram diminuição nos teores de carboidratos em comparação aos cultivados sob ↑[CO2]atm e rega diária. Entretanto, em plantas sob 400 ppm CO2 e restrição hídrica, reduções significativas nos teores de açúcares, principalmente em folhas, foram observadas. Os teores de amido não alteraram em resposta aos tratamentos de CO2 e água. Aumento no nível de prolina foi observado no início da restrição hídrica retornando a níveis basais ao longo do experimento. Nossos resultados apontam para um efeito mitigador do ↑CO2 sobre o déficit hídrico por meio da manutenção no acúmulo de carboidratos das plantas de café.
Drying of arabica coffee and its effect on the gene expression and activity of enzymes linked to seed physiological quality
(Editora da Universidade Estadual de Maringá - EDUEM, 2023) Carvalho, Mayara Holanda de; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Viias Boas; Guimarães, Cristiane Carvalho; Martins, Rayana de Sá; Clemente, Aline da Consolação Sampaio; Paiva, Luciano Vilela
The reduced longevity of coffee seeds has been attributed to their sensitivity to desiccation. Studies related to gene expression and enzyme activity in coffee seeds under drying are important for understanding the effects of drying on their physiological quality. The aim of this study was to investigate the molecular aspects of seeds under different drying methods and associate them with physiological quality. Coffee seeds with different water contents were dried both slowly and rapidly. Enzymatic activity was analysed, as well as the expression of genes that encode the enzymes superoxide dismutase, catalase, peroxiredoxins, isocitrate lyase, and endo-ß-mannanase. There was a significant effect of drying speed and final water content on enzyme activity and on the expression of the different genes analysed. In seeds under rapid drying, there was greater expression of the genes that encode the enzymes catalase and endo-ßmannanase. Greater expression of the 1 CYS PRX and SOD genes and greater activity of the ICL isoenzymes were found in seeds with superior physiological quality, but greater activity of the endo-β-mannanase and CAT enzymes occurred in seeds with lower physiological quality.
Effect of fruit load of the first coffee harvests on leaf gas exchange
(Escola de Agronomia - UFG, 2021-01-14) Muñoz, Carlos Andres Unigarro; Bejarano, Lina Marcela Díaz; Acuña, José Ricardo
Coffee production between the first and second harvest presents a difference in the fruit load with the plant age that could affect the leaf gas exchange. This research aimed to evaluate the effect of the increase in fruit load that occurs between the first and second harvest of the Coffea arabica L. production cycle on the measured gas exchange, at the two phenological stages of the fruit. The accessions E057, E318, E338 and E554 were used, as well as a completely randomized design, with three replications, using the accessions as treatments and the harvest measurements during the production cycle as the repeated measures. The variables yield per tree, number of fruits, absolute growth rates for height and stem, leaf area, leaf-to-fruit ratio and leaf gas exchange were measured across the phenological stages of fruit filling and ripening. The increase in the fruit load that occurs with age in the second harvest, if compared to the first harvest, showed a positive and significant effect on the net assimilation rate that was not expected for the obtained leaf-to-fruit ratios. Likewise, the differences in the assimilation rates were higher during the fruit-filling stage. This result suggests that the source-sink relationship may vary with the crop age and fruit phenological stage, and is not entirely depend on the leaf-to-fruit ratio.

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