Coffee Science (E-Journal)
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Incidência do bicho-mineiro do cafeeiro em lavoura irrigada sob pivô central
Full text linkThe leaf-miner (LM) [Leucoptera coffeella (Guérin-Menéville & Perrottet, 1842) (Lepidoptera: Lyonetiidae)] is one of the most powerful parasites for the coffee plants (Coffea arabica L.), being responsible for high economic losses to coffee farmers. In the last years, the adoption of irrigation systems has been becoming a common practice in Brazilian coffee farms, mainly center pivot irrigation. The principal factors that contribute to the increase of irrigated fields are the negative effects of bad rain distribution and hydric scarceness. However, there is data describing the behavior of this parasite in irrigated crops. The aim of this work was to verify the incidence of LM in a coffee fields submitted to a center pivot irrigation system with different water depths applied. The research was carried out in a experimental field with total area of 1,6 ha located in the Engineering Department of the Federal University of Lavras. The coffee trees susceptible to LM were planted in 1999, each plot with 3,5m x 0,8m of space between plants. The work was designed in randomized block model and treatments analyzed were 6 water depths applied (0, 60, 80, 100, 120 and 140% of evaporation of the class A tank - ECA) in different periods of evaluation, in a factorial scheme (6 x 12) with 3 repetitions. The LM infection in the plants was verified by visual evaluation of leaf damages caused by the parasite. The analyses were proceeded in intervals of 23 days, from April of 2004 to March of 2006. Each experimental group was composed of eight plants. Ten plagiotropics branchs were sampled in the medium part of tree, being five of the south and five of the north side of the plant. Two leaves located in the thrith or fourth pair of each branch was collected, in total of 160 leaves per experimental group. The mean dates of percentage of mined leaves were transformed using the formula (X + 0,5)1/2 and an analysis of variance was made. The results showed a significant interaction between water depths and LM incidence. The higher incidence of LM infection was observed in no irrigated plants. The experimental group submitted 140% ECA showed lower LM parasitism. The higher amount of the insects was observed in the north side of plants. Two peaks of LM incidence occurred, in January and July, with high number in the first. Entre as pragas que ocasionam perdas na cafeicultura (Coffea arabica L.), o bicho-mineiro do cafeeiro (BMC) [Leucoptera coffeella (Guérin-Menéville & Perrottet, 1842) (Lepidoptera: Lyonetiidae)] é responsável por decréscimos indiretos significativos na produção. Com os efeitos negativos da escassez hídrica e má distribuição de chuvas nos últimos anos, tem crescido, por parte dos produtores em Minas Gerais, a cafeicultura irrigada, destacando-se o cultivo sob pivô central. Entretanto, ainda pouco se conhece no sul de Minas sobre o comportamento desse inseto-praga com o uso dessa tecnologia. Objetivou-se, com este trabalho, verificar a incidência do BMC, em lavoura irrigada por aspersão tipo pivô central, submetida a diferentes lâminas de água. O estudo foi realizado na área experimental do Departamento de Engenharia da Universidade Federal de Lavras, em cafeeiro adulto com 1,6 ha da cultivar Rubi (MG 1192), suscetível ao BMC, implantado em março de 1999, com espaçamento de 3,5 x 0,8 m. O delineamento experimental foi o de blocos casualizados com três repetições e seis tipos de lâminas de água nas parcelas, que corresponderam aos tratamentos (60%, 80%, 100%, 120% e 140% da evaporação do tanque Classe "A" - ECA), além do tratamento não irrigado (testemunha) e épocas de avaliação nos 12 meses do ano, em esquema fatorial (6 x 12) e três repetições. Fez-se a avaliação do bicho-mineiro em folhas do cafeeiro, observando-se as injúrias pertinentes ao ataque do inseto-praga, em intervalos médios de 23 dias, no período de abril de 2004 a junho de 2006. A parcela foi composta por 8 plantas úteis, amostrando-se ao acaso 10 ramos plagiotrópicos do terço médio superior da planta, sendo 5 ramos da face norte e 5 ramos da face sul. Foram coletadas duas folhas localizadas no terceiro e/ou quarto par de folhas por ramo, o que totalizou 160 folhas amostradas por parcela. Os dados médios de folhas minadas coletados em cada avaliação foram transformados em (X + 0,5)1/2, submetidos à análise de variância. Houve interação significativa de lâminas de irrigação e face da planta para incidência do BMC. Houve maior incidência do BMC no tratamento não irrigado e menor incidência na maior lâmina de irrigação (140% ECA), sendo também observada maior ocorrência do inseto-praga na face norte da planta. Houve dois ligeiros picos de incidência do BMC: um no mês de janeiro e outro no mês de julho, com maior índice do inseto-praga no mês de janeiro.
Yield Stability of Indonesian Coffee Production - Comparison Between Arabica and Robusta
Full text linkCoffee is a significant commodity in Indonesia, and the two most widely cultivated coffee species are Arabica and Robusta. This study aims to compare the yield stability of Arabica and Robusta coffee in Indonesia, and the performance of regions from the viewpoint of yield stability. Using the Yield Stability Index, the study measures yield stability over a 10-year period (2011-2020) using data from Directorate General of Estates, Ministry of Agriculture. Results show, that the two coffee varieties considerably differ in their stabilities, and the stability of yields across regions also show large discrepancies. While Robusta yields were stable in all the 33 analyzed regions, though to a different extent, for Arabica, produced in 20 regions, only 4 could produce stable yields. The yield stability of Indonesian coffee is influenced by a complex interplay of environmental factors, agronomic, and socio-economic factors. Mitigating these yield stability challenges requires a multifaceted approach.
Key words: Arabica; robusta; Indonesian Coffee Yield; normal distribution; yield stability index
Determinants of the helpfulness of specialty coffee reviews on Amazon
Full text linkWith the increasing volume of online reviews on platforms like Amazon, customers must put considerable effort into isolating useful information from irrelevant or ambiguous content. One solution implemented by e-commerce sites to address this challenge is product review systems, where customers can vote on whether they find a review helpful, thereby reducing uncertainty in purchase decisions. Therefore, it is crucial to understand what makes a review helpful and how to enhance customer access to these valuable reviews. This study aims to analyze the content characteristics of online reviews that influence their perceived helpfulness in the context of specialty coffee products sold on Amazon. A content analysis was conducted on 2369 reviews to identify elements that contribute to their informational value. Subsequently, a zero-inflated negative binomial regression model was applied to test the hypotheses, addressing issues of overdispersion and an excess of zeros in the response variable. The findings suggest that aspects such as multimedia format, review depth, and the inclusion of extrinsic product attributes (price and quality) are key factors that enhance review helpfulness. On one hand, the use of images and videos helps consumers visualize the product and understand its features, while detailed and extensive reviews provide more comprehensive information. Moreover, factors like price and quality allow consumers to assess whether the product meets their needs and preferences. These findings are crucial for developing more effective marketing strategies in the coffee industry by providing a more precise understanding of the attributes most valued by consumers.
Key words: eWOM; e-commerce; negative bonimal regression; online reviews; specialty coffee
Improving the accuracy of green bean palm civet coffee purity classification using wrapper feature selection
Full text linkPalm civet coffee, a highly prized specialty coffee, faces counterfeiting due to its limited production. The lack of reliable detection methods necessitates the development of non-destructive sensing techniques. This study investigates the use of machine vision and feature selection to classify the purity of palm civet coffee. A dataset of 101 image features (11 color and 90 textural) was extracted from coffee bean images. A wrapper-based feature selection approach, employing K-Nearest Neighbors (KNN), Random Forest (RF), and Support Vector Machine (SVM) classifiers with four optimization algorithms (Bat Algorithm, Cuckoo Search, Genetic Algorithm, and Grey Wolf Optimizer), was used to identify the most informative features. The results demonstrate that a Random Forest classifier, optimized using Grey Wolf Optimizer with 500 trees, achieved the highest accuracy (0.981) using a subset of five features: Blue_Mean, Hue_Entropy, Gray_Inverse, S_HSL_Correlation, and Green_Cluster. These findings suggest that machine vision, combined with feature selection, holds promise for developing a robust and non-destructive method for detecting palm civet coffee counterfeiting.
Key words: Classifier; feature selection; learning algorithm; machine vision; palm civet coffee purity
Índices fisiológicos de mudas de Coffea arabica L. enxertadas sobre Coffea canephora
Full text linkThe analysis of growth is performed in order to explain the differences in growth of plants. This work had the objective of evaluating the development of C. arabica L. seedlings grafted with C. canephora Pierre ex Froehner. The experiment was performed in a greenhouse at the Federal University of Lavras using nutritive solution. There was used a factorial 7 x 3 + 2, with seven cultivars of C. arabica (Palma II, Catucaí 2SL, Oeiras MG 6851, Obatã IAC 1669-20, Acauã, Topázio MG 1190 and Paraíso MG H 419-1), three types of seedling (ungrafted, self-grafted and graft in the cultivar Apoatã IAC 2258) and two additional (Apoatã self grafted and Apoatã ungrafted). The results obtained showed that the grafting technique and the rootstock used did not interfere with the development of the plants, although C. arabica cultivars used showed development similar in all the three types of seedlings. A análise de crescimento tem sido utilizada para explicar as diferenças no crescimento das plantas, seja de ordem genética ou resultante de modificações do modo de cultivo. O presente trabalho teve como objetivo avaliar o desenvolvimento de mudas de cafeeiros (C. arabica L.) enxertados sobre a cultivar Apoatã IAC 2258 (C. canephora Pierre ex Froehner). O experimento foi instalado em casa de vegetação da Universidade Federal de Lavras, utilizando-se o método de cultivo em solução nutritiva. Foi utilizado um fatorial 7 x 3 + 2, sendo sete cultivares de C. arabica (Palma II, Catucaí 2SL, Oeiras MG 6851, Obatã IAC 1669-20, Acauã, Topázio MG 1190 e Paraíso MG H 419-1), três tipos de mudas (pé-franco, auto-enxertada e enxertada sobre a cultivar Apoatã IAC 2258) e dois adicionais (Apoatã auto-enxertado e Apoatã pé-franco). Com os dados obtidos foi possível concluir que a técnica da enxertia e o porta-enxerto utilizado não provocaram diminuição no desenvolvimento das plantas apesar de todas as cultivares de C. arabica utilizadas terem apresentado desenvolvimento semelhante em todos os três tipos de mudas.
Mathematical modeling of coffee beans drying: addressing challenges of determining moisture ratio under natural conditions
Full text linkCoffee bean drying is a critical step in post-harvest processing because it directly affects the quality of the final product. The moisture ratio (MR) during drying is a key parameter that must be carefully controlled to prevent over- or under-drying, both of which can degrade coffee quality. In this study, we investigate fourteen mathematical models existing in the literature that describe the MR during the drying of coffee beans. Each model is evaluated in terms of its formulation, applicability, and relevance to coffee drying. Furthermore, we numerically simulate each model using experimental drying data collected from Génova, Quindío (Colombia), under natural conditions, a region renowned for its high-quality coffee production. The simulations provide a comparison of the accuracy and predictive capability of the models under real-world environmental conditions, highlighting the need for more sophisticated models that integrate humidity, temperature, and real-time weather data to improve the accuracy and efficiency of the drying process.
Key words: Experimental data; natural drying; model evaluation; model validation; weather; integration
Coffee (Coffea arabica L.) Cup Quality Varies with Growing Environments in Ethiopia: Climate and Soil Perspectives
Full text linkThis study investigates the impact of soil composition on the quality of coffee produced across different regions of Ethiopia, with a focus on key soil nutrients— nitrogen, phosphorus, and potassium. By analyzing soil samples from Sidama, Yirgacheffe, Harrar, Jimma, and Limu, the research explores how variations in soil nutrient levels influence coffee characteristics such as flavor complexity, acidity, body, and overall quality. The results show that volcanic soils in Sidama and Yirgacheffe, with higher nitrogen and potassium levels, enhance flavor complexity and acidity, contributing to high cupping scores. In contrast, loamy and sandy soils in Jimma, Limu, and Harrar produce coffee with distinct earthy, nutty, and bold flavors, exhibiting varied acidity and body. The study highlights the critical role of soil composition in shaping the sensory profile of Ethiopian coffee and offers practical insights for farmers seekingto optimize cultivation practices. The findings also contribute to the broader understanding of terroir and its influence on coffee quality, paving the way for sustainable and innovative approaches in coffee production to meet the growing demand for high-quality specialty coffee.
Key words: soil composition; coffee quality; Ethiopia; Nitrogen; specialty coffee
Produção de frutos de cafeeiros (Coffea arabica L.) em diferentes posições e orientaçoes de ramos plagiotrópicos
Full text linkThis paper aimed at to evaluate the fruit production in different positions of coffee plagiotropic shoot (Coffea arabica L.), during eight months. Measurements started in October 21 taking five different regions of eight shoots located in the central region of a plant belonging to the cultivar of Rubi MG 1192; located at the Coffee Section from the Federal University of Lavras. The experimental design used was random blocks disposed in factorial scheme, 2x 4x 8, composed by two positions(upper third and lower third), four orientations (east sunrise, west sunset, north and south) and eight evaluations time (from October 2005 to May 2006), totalizing 64 treatments, containing 10 replicates and one plant per plot. There was a reduction in fruit number per shoot during the development and this fact was more proeminent in shoots located in the inferior part of the plant and in period from December to January. The orientations North, South, East and West did not influence the number of fruits during the development. Com o objetivo de avaliar a produção de frutos em diferentes posições de ramos plagiotrópicos em cafeeiros (Coffea arabica L.) levando em consideração os pontos cardeais, foram feitas oito avaliações mensais, iniciadas em 21 de outubro, de todos os componentes de cinco rosetas centrais em oito ramos em 10 plantas em uma lavoura da cultivar Rubi MG 1192, instalada no Setor de Cafeicultura no Campus da Universidade Federal de Lavras. O experimento foi instalado utilizando o delineamento em blocos casualizados em esquema fatorial 2 x 4 x 8 constituído de duas posições (terço superior e terço inferior), quatro orientações (leste, oeste, norte e sul) e oito épocas de avaliações (de outubro de 2005 a maio de 2006), totalizando 64 tratamentos, com 10 repetições e uma planta por parcela. Houve acentuada redução no número de frutos por roseta do cafeeiro durante o desenvolvimento da planta, sendo essa redução mais proeminente nos ramos inferiores e no período de dezembro a janeiro. As orientações Norte, Sul, Leste e Oeste não influenciam o número de frutos por roseta durante o desenvolvimento.
Utilização de mudas de raízes múltiplas na implantação de lavouras cafeeiras
Full text linkHigher production of coffee plants (Coffea arabica L.), requires abundant and deeper roots, well branched and physiologically active. However, the root grow system is a complex process, which is affected by many factors. Thus, this work aimed at to study the influence of multiple roots in the initial growth of three coffee cultivars considering the presence and absence of mulch on the planting row. The experiment was carried out at the Paineira Farm in located in the district of Bom Jesus da Penha, MG - Brazil. The experimental design was randomized in blocks with factorial scheme (2 x 3 x 2) of two types of cuttings: single and multiple rooted seedlings, three cultivars: Paraíso MG 491-1, Catuaí Vermelho IAC 99 and Catucaí Amarelo 2SL and by the presence and absence of mulch on the planting row. The parameters evaluated were the plant height (cm), the stem base diameter (mm) and number of plagiotropic branches. The results showed that plants originated from single roots presented better development in the field during the establishment of the coffee plantation. The cultivar Catuaí IAC 99 was the most sensitive, presenting reductions in the growth of the plant height, stem base diameter and the plagiotropic branches number of 22.7%, 35.2% and 52.7% respectively, when multiple rooted seedlings were considered. The use of mulch during the establishment of the coffee plantation with multiple rooted seedlings increased the growth in height of 12.6% when compared with single rooted seedlings, however with lower emission of plagiotropic branches, which are decisive for future production. Altas produções do cafeeiro (Coffea arabica L.), necessitam de raízes abundantes, profundas, bem ramificadas e ativas fisiologicamente. Devido à complexidade do processo, esse trabalho visou a verificar a influência de raízes múltiplas no crescimento inicial de plantas de três cultivares de cafeeiro, com ou sem a utilização de cobertura morta na linha de plantio. O experimento foi instalado e conduzido na Fazenda Paineira localizada no município de Bom Jesus da Penha - MG. O delineamento experimental foi em blocos casualizados em esquema fatorial (2 x 3 x 2), com dois tipos de mudas (muda com raiz única e muda com raiz múltipla), três cultivares (Paraíso MG 419-1, Catuaí Vermelho IAC 99 e Catucaí Amarelo 2SL) e pela presença e ausência de cobertura morta na linha de plantio. Avaliou-se a altura das plantas (cm), o diâmetro da base do caule (mm) e o número de ramos plagiotrópicos. Concluiu-se que plantas oriundas de mudas com raízes únicas apresentaram-se um melhor desenvolvimento na fase de implantação da lavoura cafeeira, sendo que das cultivares utilizadas, a Catuaí Vermelho IAC 99 foi a mais sensível, apresentando reduções no crescimento em 22,7%, 35,2% e 52,7% para altura de planta, diâmetro de caule e número de ramos plagiotrópicos, respectivamente, quando se utilizou mudas de raízes múltiplas. A utilização de cobertura morta na implantação de lavouras com mudas de raízes múltiplas favoreceu o crescimento em altura em 12,6% comparado com mudas de raízes únicas, porém com menor emissão de ramos plagiotrópicos decisivos para a futura produção.
Coffee productive branch growth, development and nutrient accumulation from flowering to harvest under Colombian conditions
Full text linkIn 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.
Key words: Coffea arabica L; nutrient concentration; defoliation; nutrient partitioning; Colombian coffee zone