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    Coffee productive branch growth, development and nutrient accumulation from flowering to harvest under Colombian conditions
    (Editora UFLA, 2025-05-07) Sadeghian-Khalajabadi, Siavosh; Díaz-Poveda , Vanessa Catalina; Rendón Sáenz, José Raúl
    In many Colombian regions, coffee vegetative and reproductive growth (Coffea arabica L.) occurs synchronously; hence, fertilization plans must address both needs simultaneously. The objective of the present study was to evaluate coffee productive branch growth and nutrient accumulation from flowering to harvest. During an event of high concentration of flowering, which occurred in a coffee crop, Castillo Rosario® variety, 35 plants were randomly selected, and two opposite plagiotropic branches of the same cross in the production zone were marked on each plant. One of the branches was detached at full anthesis and the other at harvest. Growth variables and nutrient concentration were measured at each time. Between flowering and harvest, branch length increased by 22 cm, number of nodes by 6.2, total biomass by 33 g, and defoliation from 14.5% to 32.5%. During this period, the concentration of all nutrients in the branch decreased, and the concentrations of N, P, Mg, and B in the leaves were lower. Total nutrient content increased differentially: N 73%, P 76%, K 142%, Ca 40%, Mg 51%, Fe 112%, Mn 87%, Zn 41%, Cu 156%, and B 36%. At anthesis, the highest proportion of nutrients was found in the leaves (57.35%-86.19%), followed by the branch (11.37%-37.41%) and flowers (1.58%-7.38%); at harvest, fruits contained the highest proportion of N, P and K, and leaves the highest contents of Ca, Mg, Fe, Mn, Zn and B. These results reveal the importance of branches and leaves in supporting nutrient demand by fruits and vegetative growth.
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    Physicochemical and sensory analysis of coffee: A determination in different parts of the plant
    (Editora UFLA, 2024-07-29) Sousa, Rachel Machado de; Paiva, Leandro Carlos
    The quality of the Arabica coffee drink (Coffea arábica L) is the result of the interaction of several factors, such as climatic conditions, terroir, altitude, nutritional factor, management aspects, stage of fruit maturation, harvest, among others. The objective was to evaluate the physical-chemical quality of coffee fruits, through the soluble solids content of coffee beans, in different parts of the plant, in order to define which position/location on the plant presents the best results in relation to sensory attributes of the drink. The analysis of soluble solids (SS) in ºBrix of cherry and raw coffee, mass grains (MMG) and sensory evaluation, the Catuaí IAC 144 variety presented better results in relation to the Paraíso MG 419- 1 variety. Regarding electrical conductivity (EC), total titratable acidity (TTA) of raw coffee, pH, color the results of the two varieties were representative for quality, the values ​​found in the analyzes are within the defined ranges. The experimental design used was randomized blocks and each variety was harvested in three blocks. Each block consisted of a plant, each plant was divided into twelve subdivisions. The treatments were arranged in a 12x2x3 factorial scheme and subjected to analysis of variance (ANOVA) and the means compared using the Scott Knott post hoc test with a significance level (p-value ≤ 0.05). The correlation matrix was used between the variables under study, in order to verify whether there is a linear relationship or not between the variable’s soluble solids ºBrix of cherry and raw coffee, aroma and body of the drink with the final average score of the tasters. Interpreting the generated equation, there is an association between body and final score, when increasing one unit in the body, an increase of 2.21 in the final score is expected. The positions on the coffee plant, upper third and lower third, in relation to the varieties Catuaí IAC 144 and Paraíso MG 419-1, were the most promising from the perspective of the results found in the physical-chemical and sensorial analysis.
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    Effect of temperature and photoperiod on Pseudomonas syringae pv. garcae inoculum production
    (Editora UFLA, 2024-11-12) Oliveira, Júlia Marques; Pozza, Edson Ampélio; Belan, Leônidas Leoni; Freitas, Marcelo Loran de Oliveira; Tedardi, Vitória Moreno
    Bacterial halo blight (BHB), whose etiological agent is the bacterium Pseudomonas syringae pv. garcae, is one of the main diseases occurring in coffee (Coffea arabica L.) leading to losses in nurseries and fields. This study aimed to assess the effect of five temperatures (20, 25, 30, 35, and 40 °C) and three photoperiods (continuous light, 12-hour light/dark, continuous dark) on the P. syringae pv. garcae inoculum concentration and the BHB progression re sulted from this inoculum, in coffee seedlings. Using a factorial design (5 x 3) with four replicates, Petri dishes inoculated with P. syringae pv. garcae were incubated for 48 hours, and the concentrations and bacterial cell dimensions were measured. The resulting inoculum was then used to inoculate coffee seedlings at 23 ± 2 °C in one leaf pair by wounding inoculation using a multi-needle apparatus. The disease severity was assessed, and the area under the disease progress curve (AUDPC) was calculated. Significant interaction (p < 0.05) between temperature and photoperiod was observed for inoculum concentration and cell dimensions. The highest inoculum concentration (2.2 x 10⁹ CFU/ml) was recorded at 25 °C under continuous light. The largest bacterial cells (4.4 µm in length and 0.7 µm in width) resulted from temperatures of 30 °C with 12-hour light/dark. For the AUDPC of BHB, a difference (p < 0.05) was observed only between inoculum production temperatures. The highest AUDPC was recorded at 25 °C, with a gradual decline observed as the temperature increased.
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    Physicochemical and sensory analysis of coffee: A determination in different parts of the plant
    (Universidade Federal de Lavras, 2024-07-29) Sousa, Rachel Machado de; Paiva, Leandro Carlos
    The quality of the Arabica coffee drink (Coffea arábica L) is the result of the interaction of several factors, such as climatic conditions, terroir, altitude, nutritional factor, management aspects, stage of fruit maturation, harvest, among others. The objective was to evaluate the physical-chemical quality of coffee fruits, through the soluble solids content of coffee beans, in different parts of the plant, in order to define which position/location on the plant presents the best results in relation to sensory attributes of the drink. The analysis of soluble solids (SS) in ºBrix of cherry and raw coffee, mass grains (MMG) and sensory evaluation, the Catuaí IAC 144 variety presented better results in relation to the Paraíso MG 419- 1 variety. Regarding electrical conductivity (EC), total titratable acidity (TTA) of raw coffee, pH, color the results of the two varieties were representative for quality, the values found in the analyzes are within the defined ranges. The experimental design used was randomized blocks and each variety was harvested in three blocks. Each block consisted of a plant, each plant was divided into twelve subdivisions. The treatments were arranged in a 12x2x3 factorial scheme and subjected to analysis of variance (ANOVA) and the means compared using the Scott Knott post hoc test with a significance level (p-value ≤ 0.05). The correlation matrix was used between the variables under study, in order to verify whether there is a linear relationship or not between the variable’s soluble solids ºBrix of cherry and raw coffee, aroma and body of the drink with the final average score of the tasters. Interpreting the generated equation, there is an association between body and final score, when increasing one unit in the body, an increase of 2.21 in the final score is expected. The positions on the coffee plant, upper third and lower third, in relation to the varieties Catuaí IAC 144 and Paraíso MG 419-1, were the most promising from the perspective of the results found in the physical-chemical and sensorial analysis.
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    Efficiency of absorption, translocation, and use of nitrogen by water-stressed coffee
    (Editora da Universidade Estadual de Maringá - EDUEM, 2024) Martinez, Herminia Emilia Prieto; Bohorquez, Cesar Augusto Avellaneda; Cecon, Paulo Roberto
    Climate change and the expansion of agricultural lands to low-fertility soils have prompted studies on the effects of water and nutritional stress on nutrient uptake and use. This study aimed to evaluate the efficiency of absorption, translocation, and use of N in coffee cultivars under water stress (WS) and different N doses. The experiment was performed hydroponically and arranged in a 4 × 2 × 4 factorial randomized block design with three replications. These factors consisted of four coffee varieties, two N doses, and four levels of WS. At the end of the experiment, the dry matter production, N concentration, and N accumulation of plants, as well as nutritional efficiency indices were evaluated. The data were subjected to analysis of variance and regression. The results showed that in plants previously well-supplied with N, N stress induces greater allocation of dry matter in roots, mitigating the effects of subsequent water deficits on shoot dry matter production. Young Mundo Novo plants subjected to N stress followed by increasing water stress maintained a high utilization efficiency (UE). Young Acauã plants well-supplied with N, maintained their N utilization efficiency up to -1.6 MPa of water stress; however, when they were N starved, they underwent a drastic reduction in UE at potentials below -0.22 MPa.
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    Uso do calcário e do gesso agrícola em duas épocas de implantação do Coffea arabica L.
    (Revista Engenharia na Agricultura, 2020-10-30) Costa, Bruna Penha; Duarte Júnior, José Barbosa; Rego, Carlos Augusto Rocha de Moraes; Costa, Antonio Carlos Torres da; Lana, Maria do Carmo
    O Brasil apresenta predominância de solos ácidos sendo necessário à sua correção para atenuar o efeito da acidez sobre as culturas agrícolas, em especial o café que é sensível ao pH baixo e a quantidade de cálcio no solo. Diante disso, o objetivo deste trabalho foi avaliar o efeito da adição de diferentes doses de calcário e gesso agrícola e seus efeitos nas características agronômicas do cafeeiro em dois experimentos com época distinta de implantação da cultura. O delineamento experimental foi em blocos casualizados, com quatro repetições em esquema fatorial 4 x 4, onde o primeiro fator foi constituído por doses crescentes de calcário e o segundo por doses crescente de gesso. O primeiro experimento foi conduzido no período do inverno - verão e o segundo experimento no período da primavera – outono. As variáveis analisadas foram altura de planta (AP), diâmetro do caule (DC), índice de área foliar (IAF), matéria seca foliar (MSF), matéria seca radicular (MSR) e comprimento radicular (CR). Ao analisar as médias dos experimentos se observou que no experimento I, a AP apresentou valores superiores a do experimento II, com acréscimo de 1,84 cm nessa variável. Para as demais variáveis DC, IAF, MSF e MSR no experimento II alcançaram um incremento superior em relação ao experimento I na ordem de 0,4 mm, 9,08 cm2, 1,54 g, 4,12 g respectivamente. As doses de calcário e gesso agrícola não proporcionaram alterações das variáveis agronômicas em ambas às épocas avaliadas, durante o período de seis meses após transplantio.
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    Pyraclostrobin preserves photosynthesis in arabica coffee plants subjected to water deficit
    (Revista Engenharia na Agricultura, 2020-02-07) Peloso, Anelisa Figueiredo; Tatagiba, Sandro Dan; Amaral, Francisco José Teixeira; Cavatte, Paulo César; Pezzopane, José Eduardo Macedo
    The objective of this study was to investigate the effect of pyraclostrobin on the photosynthetic performance of rabica coffee plants subjected or not to a water deficit, using the parameter of gas exchange (net CO2 assimilation, stomatal conductance, transpiration rate, and internal CO2 concentration and nocturnal respiration), chlorophyll fluorescence a parameters (minimum fluorescence, maximum fluorescence, maximum quantum yield of photosystem II, effective quantum yield of PSII, quantum yield of regulated energy dissipation and quantum yield dissipation non-regulated) as well as the concentrations of chloroplast pigments. In the plants maintained without water deficit, pyraclostrobin did not cause any alteration on the parameters of chlorophyll a fluorescence; however, it contributed to an increase in the level of chlorophyll a + b, CO2 assimilation and CO2 influx for the carboxylation sites of the stroma. Decreases in nocturnal respiration in plants treated with pyraclostrobin, submitted or not to water deficit seems to be a common strategy in reducing energy waste in the maintenance metabolism. Under water deficit, pyraclostrobin contributed to increase the photochemical yield, enabling plants to effectively prevent the capture, use and dissipation of light energy.
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    Drying kinetics of peeled coffee submitted to different temperatures and relative humidity of the air of drying after partial drying
    (Revista Engenharia na Agricultura, 2020-12-15) Moreira, Rodrigo Victor; Correa, Jefferson Luiz Gomes; Andrade, Ednilton Tavares de; Rocha, Roney Alves da
    The mathematical modelling is fundamental for the understanding of the related processes the drying, that influences the quality of the coffee drink. The objective of this study was to evaluate the influence of different relative humidity of the drying air after partial drying on drying kinetics of peeled coffees. Coffee fruits were harvested in the cherry stage and processed by wet, resulting in the portion of peeled coffee. Eleven treatments of drying were accomplished, being nine results of the combination of three dry bulb temperatures and three dew point temperatures, more two treatments without the control of the dew point temperatures. The control of the relative humidity by the dew point temperature was made after the grains reached the partial drying. Among the studied models, those of Diffusion Approximation and Modified Midilli were the most adequate for describing the drying process of the first and second part of drying respectively. The effective diffusivity coefficient of water in coffee grains ranged from 0.81 x 10-11 to 1.84 x 10-11 m² .s-1 during the first part of the drying and ranged from 1.49 x 10-11 to 3.29 x 10-11 m² .s-1 during the second part of the drying, increasing significantly with the reduction of the dew point temperature and increase of the dry bulb temperature.
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    Initial vegetative development and early selection of arabica coffee cultivars in a low-altitude region
    (Instituto Agronômico (IAC), 2023-11-10) Filla, Vinícius Augusto; Coelho, Anderson Prates; Grossi Terceiro, Matheus; Morello, Orlando Ferreira; Lemos, Leandro Borges
    The cultivation of Coffea arabica L. in a low-altitude region is a sustainable alternative for diversifying the income of farmers. On account of the variability of available cultivars, the use of indirect selection through initial vegetative development may be an auxiliary tool for identifying the most suitable genotypes for this environment. This study aimed to identify the dwarf Arabica coffee cultivars with better initial development in a low-altitude region and the morphological traits with greater relevance for the early selection of cultivars with high yield potential. The experiment was installed in the northeast of São Paulo, Brazil. The experimental design used was randomized blocks with four replications. The treatments consisted of 17 dwarf Arabica coffee cultivars. There is variability among dwarf Arabica coffee cultivars for initial vegetative development. The growth and increase in the number of nodes of the plagiotropic branch can be used in early selection to identify cultivars with greater yield potential. The cultivars IAC Obatã 4739, Obatã IAC 1669-20, and Tupi IAC 1669-33 present higher initial vegetative performance in low-altitude environments. The results obtained are useful to breeders and producers for choosing the cultivars best adapted to cultivation in this environment.
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    Proposed diagrammatic scale to assess heat injury in coffee seedling canopy
    (Editora da Universidade Estadual de Maringá - EDUEM, 2023-04-28) Resende, Laís Sousa; Pozza, Edson Ampélio; Pereira, Renata Cristina Martins; Botrel, Élberis Pereira; Roteli, Karolaine de Cássia; Oliveira, Júlia Marques
    A diagrammatic scale with five levels (0, 0.1 - 2.0, 2.0 - 6.0, 6.0 - 10, and 10 - 14) was developed and evaluated to measure the symptoms of heat injury in a coffee seedling canopy. The scale was constructed to increase assessment efficiency and align the estimations more closely with the actual values. Two assessments with the diagrammatic scale and one without were conducted with an interval of seven days. The evaluators using the proposed scale presented estimates with better levels of precision, accuracy, reproducibility, and repeatability than those using a conventional method. The proposed diagrammatic scale was shown to provide a reliable estimate for assessing the symptoms of heat injury on the canopy of in Coffea arabica L. seedlings. Therefore, it is possible to standardize heat injury evaluation methods using this diagrammatic scale, allowing for data comparisons with different cultivars.