Revista Ciência Agronômica
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Resultados da Pesquisa
Item Quality of coffee planting techniques by aerial sensors and statistical process control(Universidade Federal do Ceará, 2024) Santana, Lucas Santos; Ferraz, Gabriel Araújo e Silva; Cunha, João Paulo Barreto; Marin, Diego Bedin; Bento, Nicole Lopes; Faria, Rafael de OliveiraPlanting is considered one of the most essential steps in coffee growing. Lack of uniformity in planting may compromise future operations. Therefore, verifying planting operations quality is fundamental to optimizing production processes and reducing costs. This study aimed to investigate planting techniques through Statistical Process Control (SPC) and aerial images. Carried out in two areas, managed manually and semi-mechanized in the Bom Jardim Farm (MG - Brazil). Data were collected through Remotely Piloted Aircraft (RPA). Quality control charts and density maps were used to identify variations in distribution and spacing between plants and planting rows. It was found that the planting carried out manually was 4.7% wider than projected due to spacing reduction from 0.5 m to 0.48 m. The semi-mechanized system displayed a deficit of 7% compared to the projected planting system, using 0.55 m between plants. The density map showed the most significant planting alignment variations. Despite displaying lower results than the manual system, the semi-mechanized system improvements are valid for their minimal average variations. Thus, correcting points found outside the limits can increase the efficiency of semi-mechanized planting.Item Lógica fuzzy na avaliação da fertilidade do solo e produtividade do café conilon(Universidade Federal do Ceará, 2010) Silva, Samuel de Assis; Lima, Julião Soares de Souza; Souza, Gustavo Soares de; Oliveira, Rone Batista de; Xavier, Alexandre CândidoO objetivo deste estudo foi analisar, utilizando a geoestatística e o sistema de classificação fuzzy, a fertilidade de uma área experimental com base em atributos químicos do solo e sua relação com a produtividade do café conilon. O estudo foi realizado na fazenda experimental do INCAPER-ES. As amostras de solo foram coletadas na profundidade de 0 - 0,2 m, sendo analisados os atributos: fósforo, potássio, cálcio e magnésio, alumínio, soma de bases, capacidade de troca catiônica a pH 7 e saturação por bases. Os dados foram submetidos a uma análise descritiva, exploratória e à analise geoestatística. Utilizou-se um sistema de classificação fuzzy utilizando os atributos descritos para inferir sobre a fertilidade do solo e sua relação com a produtividade da cultura. A possibilidade de fertilidade apresentou relação espacial positiva com a produtividade da cultura, com valores mais elevados desta onde a possibilidade de solo fértil é superior.Item Desafios da mulher na cafeicultura Grupo Cafeína COCATREL, Três Pontas - MG(UNIS- VARGINHA, 2022-11-01) Archanjo, Larissa Evely; Brigante, Giselle PradoA região do Sul de Minas é reconhecida mundialmente pela produção rural, principalmente a produção cafeeira, de importância econômica regional e nacional, para o agronegócio. No entanto, o papel da mulher na cafeicultura contribui notavelmente para o crescimento do cenário de produção rural. Assim, o presente estudo considerou pesquisar sobre a inserção feminina no mercado, averiguando as comparações de gênero e a atuação da mulher na atualidade, na cadeia produtiva. Inicialmente, foi realizada uma busca exploratória, através da investigação de artigos científicos publicados online, para embasamento desta discussão. Utilizou-se como método uma pesquisa descritiva e qualitativa, a partir de questionário estruturado e composto por questões de múltipla escolha direcionada as mulheres produtoras rurais, empresárias do ramo, técnicas que compõem o Grupo Cafeína (COCATREL), da cidade de Três Pontas, Minas Gerais. Fizeram parte do questionário perguntas que envolveram os desafios das mulheres na cafeicultura, como a remuneração mensal, maternidade e inseguranças. Ao analisar os dados obtidos, com apoio de ferramentas e autores selecionados, foi possível discutir e apresentar um material para a discussão sobre a equidade de gênero no campo. E assim proporcionar um trabalho com o intuito de produzir resultados relevantes e promover um estudo científico para o entendimento da atuação das mulheres na produção rural local, no presente e no futuro das próximas gerações. Com a pesquisa pôde-se perceber que ainda existe uma insatisfação com as condições encontradas no mercado de trabalho e uma expressiva discriminação.Item A mixed model applied to joint analysis in experiments with coffee blends using the least squares method(Universidade Federal do Ceará, 2019) Paulino, Allana Lívia Beserra; Cirillo, Marcelo Angelo; Ribeiro, Diego Egídio; Borém, Flávio Meira; Matias, Gabriel CarvalhoThe aim of the present study was to propose a mixed model for a sensory analysis of four experiments with blends of different standards of quality, including the species Coffea Arabica L. and Coffea Canephora. Each experiment differed in the proportions used to formulate the blends and the concentrations used in preparing the beverages, these being 7% and 10% coffee powder for each 100 ml of water. The response variables under analysis were the sensory characteristics of the beverage found in an assessment made by a group of trained tasters, considering taste, bitterness and a final score. Each description followed a numerical rating scale of intensity that ranged from 0 to 10. The model was implemented using the least squares method; this led to the conclusion that including random parameters in the model, represented by the experiments, made it possible to compare the effect of each component simultaneously for each of the experiments.Item Monte Carlo simulation and importance sampling applied to sensory analysis validation of specialty coffees(Universidade Federal do Ceará, 2021) Ferreira, Haiany Aparecida; Liska, Gilberto Rodrigues; Cirillo, Marcelo Ângelo; Borém, Flávio Meira; Ribeiro, Diego Egídio; Cortez, Ricardo MiguelCoffee sensory analysis is usually made by a sensory panel, which is formed by trained tasters, following the recommendations of the Specialty Coffee Association of America. However, the preference for a coffee is commonly determined by experimentation with consumers, who typically have no special skills in terms of sensory characteristics. Therefore, this study aimed at applying an intensive computational method to study sensory notes given by an untrained sensory panel, considering the probability distributions of the class of extreme values. Four types of specialty coffees produced under different processes and in varied altitudes in the mountainous region of Mantiqueira, Minas Gerais, were considered. We concluded that the generalized Pareto distribution can be applied to sensory analysis to discriminate types of specialty coffees. Furthermore, the method of importance sampling by Monte Carlo simulation showed greater variability considering a probabilistic model adjusted to identify specialty coffees.Item Growth and physiological quality in clonal seedlings of Robusta coffee(Universidade Federal do Ceará, 2020) Giuriatto Júnior, Jurandyr José Ton; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Vasconcelos, Jaqueline Martins; Campanharo, MarcelaThe intrinsic characteristics of the vegetative propagule may influence the rooting speed and shoot growth, as well as the final physiological quality of clonal seedlings of Coffea canephora. The aim of this study was to evaluate the growth and physiological quality of ‘Robusta’ coffee seedlings produced from propagules (stem cuttings) with different cutting ages. The study was conducted in a greenhouse, in the district of Ouro Preto do Oeste, in Rondônia, Brazil (10˚45’43” S and 62˚15’10” W). The ages of the cuttings were 30, 60, 90, 120 and 150 days, corresponding to five positions on the secondary orthotropic stem (sprout), from the apex to the base. Dry matter accumulation, and relative and absolute growth rates were evaluated for 188 days after cutting, as well as the vegetative characteristics of the seedlings at 125 days after cutting. It appears that growth can be divided into three phases: 1) Initial: slow growth, lasting approximately 83 days; 2) Intermediate: fast growth, lasting approximately 40 days; and 3) Final: slow growth, starting approximately 125 days after cutting. With physiological quality, although all the cuttings showed similar growth curves, those of 60, 90 and 120 days produced, 125 days after cutting, the best vegetative performance in the seedlings.Item Kahweol and cafestol in coffee brews: comparison of preparation methods(Universidade Federal do Ceará, 2020) Wuerges, Karla Leticia; Dias, Rafael Carlos Eloy; Viegas, Marcelo Caldeira; Benassi, Marta de ToledoThe profile of bioactive compounds in coffee brews depends on the coffee bean species and varieties, harvesting and post-harvesting practices, roasting processes, and also on the brewing method. The present research aimed to study the contents of cafestol and kahweol - coffee diterpenes with a known impact on human health – comparing coffee beverages prepared using common brewing methods (filtered, espresso, and instant coffee brews). Filtered (cloth-filtered and paper-filtered), espresso and instant brews were obtained from a medium-roasted Coffea arabica coffee (NY 2). Five genuine replicates of each coffee brew were prepared, and the extracts were lyophilized. A validated UPLC-based method provided the content of diterpenes. The results were reported in mg of diterpene per g of solids or per a standard dose of 50 mL of coffee brew. Solids content of coffee brews ranged from 2.06 to 2.46 g 100 mL-1. All coffee brews presented low diterpene contents: 0.05 to 0.16 mg of kahweol and 0.11 to 0.14 mg of cafestol 50 mL-1. Instant coffee brew showed the lowest content of kahweol and absence of cafestol; this reduction was related to the production process of soluble coffee. Diterpenes content was similar in espresso and paper-filtered brews. The cloth-filtered coffee had lower solids content, but higher levels of diterpenes (in mg g-1 of solids). Similar cafestol and kahweol contents (mg 50 mL-1) were observed in filtered and espresso brews.Item Water-retaining polymer and seedling type when planting irrigated coffee(Universidade Federal do Ceará, 2016-04) Souza, Antonio Jackson Jesus; Guimarães, Rubens José; Dominghetti, Anderson William; Scalco, Myriane Stella; Rezende, Tiago TeruelThe aim of this work was to evaluate the use of a water-retaining polymer on the initial growth of coffee plants for different levels of irrigation and types of seedling. The experiment was set up in pots with a clayey soil, in a greenhouse of the Sector for Coffee Production of the Federal University of Lavras, Brazil. The experiment was arranged in a randomised block design into sub-lots with three replications, giving a total of 48 experimental units. Four levels of irrigation (25%, 50%, 75% and 100% of the available water) were randomly assigned to the lots; the type of seedling (grown in bags or tubes) were randomly assigned to the sub-lots, and the use or not of the water-retaining polymer randomly assigned to the sub-sub-lots. In the treatments with water-retaining polymer, a dilution of 1.5 Kg of polymer to 400 litres of water was used at a dose of 1.5 litres of solution per plant. The following were evaluated at intervals of 60 days during the experiment (360 days from planting): stem diameter, plant height, leaf area, number of leaves and number of plagiotropic branches on the coffee plants. Hydrated water-retaining polymer favoured the growth of coffee plants under an irrigated system. Irrigation resulted in greater plant growth, with the seedlings grown in bags showing more growth than those grown in tubes.Item Alternative for the evaluation of coffee seedlings using Fisher’s discriminant analysis(Universidade Federal do Ceará, 2016-04) Campos, Katia Alves; Morais, Augusto Ramalho de; Paixão, Crysttian ArantesOne of the applications of Fisher’s linear discriminant function (FDF) is its use in transforming multivariate data into a new univariate variable. This then makes possible a new option for the variance analysis of multivariate data, in addition to the multivariate analysis of variance (MANOVA). The aim of this work was to select groups of seven characteristics of quality in coffee seedlings using six criteria for selection, to use the FDF to transform such groupings of characteristics into a new variable, and then to compare interpretation of the results obtained from the univariate and multivariate analyses of variance of the characteristics and this new variable, with a view to its use in evaluating coffee seedlings. A randomised block design was used to assess the effect of organic fertiliser on the formation of seedlings in coffee cv. Catuaí Vermelho IAC- 44, evaluating the following characteristics: seedling height, diameter, root length, dry weight of shoots and roots, leaf area, number of leaves and total dry weight. According to the selection criteria used, different subsets of the selected characteristics are possible. The use of the FDF is shown to be viable in discriminating between treatments. Univariate analysis of the new variable obtained with the FDF and multivariate analysis (MANOVA) was able to detect differences between the treatments, however, it is simpler to apply FDF methodology.Item Mathematical models applied to the optimisation of mixtures in the production of silage from coffee by-products(Universidade Federal do Ceará, 2017-04) Malta, Marcelo Ribeiro; Cirillo, Marcelo Ângelo; Fassio, Larissa de Oliveira; Barcelos, Adauto Ferreira; Lima, Priscilla Magalhães deThe aim of this work was to propose a mathematical model to determine the best combination of the by- products of coffee processing in the production of silage. To this end, 13 treatments were evaluated, resulting from the combination of wet coffee husks (WCH) and dried coffee husks (DCH), both with and without the use of molasses (M) and with or without the use of the inoculant Lactobacillus plantarum (I). From these components, various mixtures were proposed and evaluated, using the technique of simultaneous optimisation of multiple response variables. Silages with the best characteristics were obtained from the use of 76.40% WCH, 18.77% DCH, 4.83% of M and 0.0001% I.
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