Revista Ceres
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Resultados da Pesquisa
Item Resilience to water deficit of coffee seedlings produced through cuttings and somatic embryogenesis(Universidade Federal de Viçosa, 2024-12-16) Dominghetti, Anderson William; Freitas, Tainah; Silveira, Helbert Rezende de Oliveira; Guimarães, Rubens JoséInformation on Coffea arabica L. vegetatively propagated during crop establishment is still scarce. Knowledge on the anatomical and physiological adaptation of these types of plants in the crop formation phase, in conditions of water deficit is important. The objective of this work was to understand the anatomical and physiological adaptations of plants derived from cuttings and somatic embryogenesis as resilience to water deficit in the implantation phase of the crop. Both types of plants were submitted to 20%, 40%, 60%, 80% and 100% of water available in the soil, in a controlled environment, for 153 days. The design used in this experiment was the randomized blocks with five replications. Physiological characteristics (photosynthetic activity, stomatal conductance, transpiration and instantaneous carboxylation efficiency) and anatomical characteristics (palisade parenchyma thickness and stomatal density) were evaluated. Both types of plants are resilient to water deficit in the planting phase of the crop. Cutting plants have greater photosynthetic activity and palisade parenchyma thickness with greater growth potential. In general, somatic embryogenesis plants have higher stomatal density. Plants of both types of seedlings have lower values of transpiration, stomatal conductance and CO2 assimilation under water deficit conditions, but with higher stomatal densities, as an adaptation response.Item Morphology of the coffee root system using polyethylene film(Universidade Federal de Viçosa, 2023-08-25) Nascimento, Letícia Gonçalves do; Assis, Gleice Aparecida de; Fernandes, Marco Iony dos Santos; Caixeta, Lucas Gomes; Carvalho, Fábio Janoni; Mazziero, Beatriz GallucciIn the initial phase of the coffee crop, the control of weeds and water availability for the establishment of the plants is a concern. The polyethylene cover can positively influence the chemical and biological characteristics of the soil and, consequently, the root system. The objective of this work was to evaluate the morphology of the root system of coffee plants using polyethylene mulching of different widths and colors. Coffee was planted in December 2016 using the cultivar Topázio MG-1190. A randomized repetitions design was used, with four blocks and five treatments, as follows: 1.20-m wide white/black mulching, 1.40-m white/black mulching, 1.20-m silver/black mulching, 1.40-m silver /black mulching, and no mulching. Total root dry matter per soil volume, total root length per soil volume, total root volume per soil volume, total root area per soil volume, specific root surface, specific root length, and mean root diameter were all evaluated. Roots with smaller diameters were concentrated in the 0-0.20 m depth layer, while in the 0.20-0.40 m depth layer, roots with larger diameters were found. Plants grown in 1.20-m silver/black mulching showed a greater surface area and a specific length of the roots.Item Variability of photosynthetic performance among improved genotypes of Coffea canephora(Universidade Federal de Viçosa, 2025-05-09) Colodetti, Tafarel Victor; Tomaz, Marcelo Antonio; Rodrigues, Wagner Nunes; Christo, Bruno Fardim; Martins, Lima Deleon; Cavatte, Paulo CezarThis study evaluated the variability of photosynthetic performance of 27 improved genotypes of Conilon coffee, cultivated in the Southern of the Espírito Santo State. The photosynthetic performance was based on the measurement of gas exchange rates and chlorophyll in the period most favorable to the photosynthetic activity and in different stages of the reproductive cycle: flowering, fruit initiation, grain formation and fruit maturation; being expressed as the average (weighted by the number of days) along the phenological stages of the third reproductive cycle of the plants. It was possible to verify the existence of sufficient variability to differentiate the photosynthetic performance among the 27 genotypes throughout the reproductive cycle, even starting from a group of already improved genotypes. Among the physiological parameters, the rate of carbon assimilation, stomatal conductance and the transpiration rate stood out as parameters for the study of variability, mainly due to their contributions to the clustering of genotypes. The genotype 108 is highlighted due to its high photosynthetic rate, associated with higher relative content of chlorophyll, as well as reasonable water use efficiency. The genotypes 205, 206 and 305 stood out in terms of water use and carbon assimilation.Item Clonal cutting production by Coffea canephora mother plants under increasing nitrogen doses(Universidade Federal de Viçosa, 2024-12-16) Kolln, Alana Mara; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Campanharo, Marcela; Rocha, Rodrigo Barros; Giuriatto Júnior, Jurandyr José TonThis study aimed to establish production curves of cuttings for Coffea canephora coffee plants in response to nitrogen doses. A clonal garden of the botanical variety Robusta was used to evaluate the effects of seven nitrogen doses divided into four applications. The subplots corresponded to two evaluation periods: January and June 2019. The following traits were evaluated: number of stems, number of viable cuttings, number of cuttings per stem, cutting fresh and dry mass, and cutting macronutrient contents. The results showed that C. canephora produced a higher amount of vegetative mass and propagules during the period from September to January compared to the period from January to June. Nutrient concentrations in the tissues varied with the period of the year due to soil nutrient availability and the amount of accumulated dry mass. Increasing nitrogen doses resulted in higher vegetative and propagules mass associated to higher nitrogen and potassium concentrations in the cuttings; but had no effect on phosphorus, calcium, magnesium, and sulfur contents. Nutrient contents in the cuttings followed the order K>N>Ca>P>Mg>S regardless of the applied nitrogen dose.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 Use of Cladosporium sp. as a bioprotector of coffee quality in different post-harvest conditions(Universidade Federal de Viçosa, 2023-11-13) Paiva, Felipe Aparecido de; Melo, Bruno Manoel Rezende de; Ferreira, Sindynara; Oliveira, Emanuelle Morais de; Santos, Telma Miranda dos; Castro, Douglas GoulartThe pre-harvest application of the bioprotective agent Cladosporium cladosporioides is an alternative to inhibit these fermentative processes that might occur in coffee beans that were either their storing bag or exposed to simulated rain, because a controlled amount of water was applied to the coffee. The objective of this study was to evaluate the effect of Cladosporium cladosporioides (Fresen) de Vries in the physical-chemical and sensory of the coffee beans. The study was conducted in an arabica coffee plantation, in the municipality of Inconfidentes, state of Minas Gerais, Brazil. In this study used four different doses of the bioprotector and three different pos-harvest conditions. The sour defective coffee beans, electrical conductivity, total titratable acidity, soluble solids, color and it was determined the general quality of coffee of both the left-in-bag and rainfall-exposed variants were positively influenced by the bioprotector. The bioprotector promoted an increase in the quality of the physical and chemical composition and sensory quality of rainfall and left-in-bag coffees compared to coffee beans without bioprotector. The bioprotector also maintained quality in rainfall and left-in-bag coffee when compared with the yard-grown variant. The sensory quality of the yard-grown coffeed was not influenced by the bioprotector.Item Morphology of the coffee root system using polyethylene film(Universidade Federal de Viçosa, 2023-08-25) Nascimento, Letícia Gonçalves do; Assis, Gleice Aparecida de; Fernandes, Marco Iony dos Santos; Caixeta, Lucas Gomes; Carvalho, Fábio Janoni; Mazziero, Beatriz GallucciIn the initial phase of the coffee crop, the control of weeds and water availability for the establishment of the plants is a concern. The polyethylene cover can positively influence the chemical and biological characteristics of the soil and, consequently, the root system. The objective of this work was to evaluate the morphology of the root system of coffee plants using polyethylene mulching of different widths and colors. Coffee was planted in December 2016 using the cultivar Topázio MG-1190. A randomized repetitions design was used, with four blocks and five treatments, as follows: 1.20-m wide white/black mulching, 1.40-m white/black mulching, 1.20-m silver/black mulching, 1.40-m silver /black mulching, and no mulching. Total root dry matter per soil volume, total root length per soil volume, total root volume per soil volume, total root area per soil volume, specific root surface, specific root length, and mean root diameter were all evaluated. Roots with smaller diameters were concentrated in the 0-0.20 m depth layer, while in the 0.20-0.40 m depth layer, roots with larger diameters were found. Plants grown in 1.20-m silver/black mulching showed a greater surface area and a specific length of the roots.Item Multispectral images for discrimination of sources and doses of fertilizer in coffee plants(Universidade Federal de Viçosa, 2023-06-16) Rezende, Camila Isabel Pereira; Assis, Gleice Aparecida de; Martins, George Deroco; Carvalho, Fábio Janoni; Franco, Miguel Henrique Rosa; Araújo, Nathalia Oliveira deRemote monitoring of the management of coffee crops is necessary as the demand in decision-making, where the aim is to rise production based on sustainable management is in a constant growth. In this work, it was evaluated the potential of images obtained by low-cost sensors in the discrimination of sources and doses of mineral and organomineral fertilizers in coffee. The experimental design was in randomized blocks, with five blocks and six treatments, as follows: (T1) - 100% of the organomineral treatment; (T2) - 70% of the organomineral treatment; (T3) - 50% of the organomineral treatment; (T4) - 100% of mineral fertilization; (T5) - standard treatment of the farm and (T6) - 70% of mineral fertilization. After management, we used the Mapir 3 Survey3W camera coupled to an ARP drone – Phantom4 to take images of the experiment over a 12-month vegetative period. Combined with image taking, it was collected agronomic parameters of coffee growth and productivity for two crops and concluded that different fertilization doses did not significantly affect the analyzed parameters. Based on the supervised classification of multispectral images, it was possible to discriminate treatments with a higher degree of accuracy (86.66% accuracy) than when analyzing coffee growth parameters.Item Agronomic performance and productivity of Arabica coffee intercropped with timber species(Universidade Federal de Viçosa, 2023-04-14) Freitas, Ana Flávia de; Fonseca, Arley José; Volpato, Margarete Marin Lordelo; Carvalho, Gladyston Rodrigues; Venturin, Regis Pereira; Silva, Vânia AparecidaThe insertion of the tree component in coffee production is a strategy from an economic and environmental perspective. Thus, the objective of this study was to evaluate the temporal influence on the agronomic and productive performance of the coffee crop under the interference of different tree species as a function of spacing. The experiment was set in the municipality of Santo Antônio de Amparo-MG, in 2012, and conducted in a randomized block design with four replications. The treatments were: cultivar ‘Catuai Vermelho IAC 99’ in monoculture (3.40 m x 0.65 m) and intercropped with African mahogany, teak and pink cedar, in two spacings (9 x 13.6 m and 18 x 13.6 m), in coffee rows. Three coffee rows were fixed between rows, totaling 13.6 m. The following variables were evaluated: height (m), stem diameter (cm), crown diameter (m), productivity (bags ha-1) and yield (l/sc) for coffee. From the evaluations, there is a significant effect of height, productivity and yield for the coffee crop. The system intercropped with tree species did not influence coffee productivity and yield until the 3rd harvest and, for the 5th harvest, intercropping with mahogany favored productivity, although the accumulated productivity did not show any treatment effect.Item Influence of humus on chromium absorption by coffee seedlings grown on substrate containing tannery sludge(Universidade Federal de Viçosa, 2023-03-10) Berilli, Sávio da Silva; Oliveira, Dhiego da Silva; Martineli, Leonardo; Pereira, Lucas Louzada; Cunha, Maura da; Pireda, SauloChromium is present in the tannery sludges worldwide making it a problem for agriculture. This study aimed to evaluate whether humus functions as a chromium stabilizing agent when using tannery sludge in the substrate of conilon coffee seedlings (Coffea canephora) and to determine what effects there are on leaf development and anatomy. Treatments consisted of a fixed dose of tannery sludge (30% of volume) on substrates of conilon coffee seedlings with different proportions of humus and subsoil (T-10, T-20, T-30, T-40% of humus). Information for the evaluation of leaf anatomy and seedling development was collected at 180 days after the planting of cuttings. From the phenological point of view, the treatments that best promoted seedling quality were T-30 and T-40. However, the greater the amount of humus in the substrate the greater the absorption of chromium by plants, which directly affected the organization of epidermal cells and leaf mesophyll. In addition, intense cytoplasmic degradation, ultrastructural changes in chloroplasts and mitochondria, and an increase in autophagic vacuoles were observed. We conclude that increasing the amount of humus in substrate with tannery sludge provides higher quality coffee seedlings, despite promoting greater absorption of chromium by plants and the consequent major intracellular disturbances.
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