Acta Scientiarum Agronomy

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/11111

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Adubação foliar de sulfato de zinco na produtividade e teores foliares de zinco e fósforo de cafeeiros arábica
(Editora da Universidade Estadual de Maringá - EDUEM, 2009-01) Pozza, Adélia Aziz Alexandre; Guimarães, Paulo Tácito Gontijo; Silva, Enilson de Barros; Bastos, Ana Rosa Ribeiro; Nogueira, Francisco Dias
Para avaliar a dose e a forma de aplicação de sulfato de zinco foliar no crescimento e produtividade do cafeeiro Mundo Novo, instalou-se um experimento de campo em LATOSSOLO VERMELHO Distroférrico, na Fazenda Experimental da Epamig em São Sebastião do Paraíso. O delineamento experimental foi em blocos casualizados, em esquema fatorial 4 x 2, com cinco repetições e parcela de 30 plantas com seis úteis. As quantidades de sulfato de zinco (ZnSO 4 ) foram aplicadas nas concentrações de 0; 0,5; 1,0 e 1,5%, testadas em duas ou quatro aplicações por ano agrícola. Foram avaliados por oito anos os teores foliares de P e Zn e as produções. Concluiu-se que o cafeeiro respondeu positivamente às aplicações de doses crescentes de ZnSO 4 via foliar, aumentando a produção e também os teores foliares de Zn. Maior número de pulverizações de ZnSO 4 em menores concentrações foi superior aos tratamentos com menor número de pulverizações mais concentradas, promovendo maiores produções. As produções máximas foram obtidas com doses de 10,8 e 12,6 kg ha-1 de ZnSO 4 , para duas e quatro aplicações anuais, respectivamente. Sugerem-se valores entre 10 e 28 mg kg-1 como faixa crítica foliar de Zn, e valores de 100 a 150 para relação P/Zn.
Analysis of the coffee harvesting process using an electromagnetic shaker
(Editora da Universidade Estadual de Maringá - EDUEM, 2010-07) Santos, Fábio Lúcio; Queiroz, Daniel Marçal de; Pinto, Francisco de Assis de Carvalho; Santos, Nerilson Terra
Harvesting is one of the most important operations in coffee production systems. This operation has a high cost and impact on the final quality of the product. To reduce production costs, producers are looking for ways to mechanize this operation. Harvesting machines generally detach fruits from the coffee plant by vibration and/or impact. The objective of this work was to study the effect of the amplitude and frequency of vibration on the efficiency of coffee fruit harvesting. Vibration tests of coffee branches were performed in a laboratory using an electromagnetic shaker. The tests were performed using amplitudes in the range of 3.75 to 7.50 mm and frequencies from 13.33 to 26.67 Hz. Coffee branches from two different varieties were used for evaluation, Catuaí Vermelho and Mundo Novo. It was verified that harvesting efficiency is directly related to the acceleration reached by the fruits during the harvesting process. The frequencies of 23.33 and 26.67 Hz and amplitudes of 6.25 and 7.50 mm resulted in the highest harvesting efficiency of ripe coffee cherries for both varieties. However, the harvesting efficiency for the Mundo Novo variety was higher than that of the Catuaí Vermelho variety at the studied frequency and amplitude ranges in this work.
Application rate and hydraulic tips used in remotely piloted aircraft affect the phytosanitary products in coffee plant canopies
(Editora da Universidade Estadual de Maringá - EDUEM, 2024) Alvarenga, Cleyton Batista de; Zampiróli, Renan; Cunha, João Paulo Arantes Rodrigues da; Rinaldi, Paula Cristina Natalino; Cunha, Bruno Amâncio da; Faria, Layanara Oliveira
Most coffee (Coffea arabica) phytosanitary management techniques are performed using ground-based equipment, and remotely piloted aircraft are a recent alternative. Therefore, this study evaluates the effect of different application rates and hydraulic tips used for spreading phytosanitary products on coffee crops using a remotely piloted aircraft, assisted by artificial targets and dye tracing. The experiment was a 4 × 3 factorial randomized block design with four tips (XR 110-01, TT 110-01, AIXR 110- 015, and TTJ60 110-02) and three application rates (8, 12, and 16 L ha-1 ). Hydrosensitive paper was used to analyze the droplet spectrum, and the Brilliant Blue tracer was used to detect spray deposition. The DJI Agras T20 remotely piloted aircraft was used to apply the phytosanitary product. Speed, flight height, and application range were maintained at 5.56 m s-1 , 2 m, and 5 m, respectively. The flight direction was perpendicular to the crop planting lines. The application rate and hydraulic tip jointly controlled the accumulation of droplets on the target according to its position in the plant canopy. Therefore, remotely piloted aircraft can be used in coffee phytosanitary management, particularly to control targets that predominately occur in the upper third of the plant canopy.
Avaliação de compostos não - voláteis em diferentes cultivares de cafeeiro produzidas na região sul de Minas Gerais
(Editora da Universidade Estadual de Maringá - EDUEM, 2009-01) Malta, Marcelo Ribeiro; Chagas, Sílvio Júlio de Rezende
O presente trabalho teve como objetivo avaliar os teores de trigonelina, ácidos clorogênicos (5-ACQ) e cafeína em grãos de diferentes cultivares de cafeeiro (Coffea arabica L.). As cultivares avaliadas foram coletadas na Fazenda Experimental da Epamig em Lavras, Estado de Minas Gerais, no ano agrícola de 2005/2006. O delineamento experimental utilizado foi um inteiramente casualizado constando de oito cultivares de café com três repetições. Foram avaliadas as cultivares: Oeiras MG 6851, Acaiá Cerrado MG 1474, Catuaí Vermelho IAC 99, Rubi MG 1192, Topázio MG 1190, Mundo Novo IAC 379/19, Catucaí Amarelo 2 SL e Catuaí Amarelo IAC 62. Após a colheita dos cafés por derriça manual no pano, estes foram lavados e submetidos ao processo de descascamento e despolpamento. Depois dos grãos serem despolpados, foram secados em terreiro de cimento até atingirem 11%-12% de umidade. Os grãos de café beneficiados foram então moídos para a realização das análises de cafeína, trigonelina e 5-ACQ por cromatografia líquida de alta eficiência. Os resultados obtidos permitiram concluir que existem diferenças nos constituintes não- voláteis entre as cultivares estudadas nas condições ambientais de cultivo similares para todas cultivares. Catuaí Amarelo IAC 62 e Rubi MG 1192 apresentaram os maiores teores de trigonelina; Catuaí Amarelo IAC 62, Catuaí Vermelho IAC 99, Rubi MG 1192 e Oeiras MG 6851 apresentaram os maiores teores de 5-ACQ; o menor teor de cafeína foi observado na cultivar Oeiras MG 6851, seguida pela cultivar Mundo Novo IAC 379-19.
Beverage quality of Coffea canephora genotypes in the western Amazon, Brazil
(Editora da Universidade Estadual de Maringá - EDUEM, 2021) Morais, Johnnescley Anes de; Rocha, Rodrigo Barros; Alves, Enrique Anastácio; Espindula, Marcelo Curitiba; Teixeira, Alexsandro Lara; Souza, Carolina Augusto de
This study aimed to evaluate the beverage quality of Coffea canephora genotypes in different environments of the western Amazon to assist plant selection and new cultivar development. To analyze beverage quality, samples of cherry coffee beans were collected separately for each genotype from clonal competition trials installed in the municipalities of Ouro Preto do Oeste, Alta Floresta do Oeste, Porto Velho, and Ariquemes in Rondônia State and Rio Branco in Acre State (Brazil). The beverage quality was assessed using the Robusta Cupping Protocol, which attribute to each genotype a score in a range from 0 to 100, highlighting nuances. Analysis of variance and principal components using reference points were used to quantify genotype x environment interaction (G x E). The analysis of variance indicated that genotypic and G x E interaction effects were significant (p < 0.01). By using a centroid dispersion method, we could identify four clones of low, eight of specific (to favorable or unfavorable environments), and seven of broad adaptability to the environments. The clones BRS 2314, 11, and 17 had average quality scores above 80 in all environments, with potential for specialty coffee production. The clones BRS 1216, BRS 3220, and BRS 3193 presented unstable behavior, with beans of higher quality in some of the evaluated environments. Such inconsistency in clone behavior is caused by unpredictable changes in plant performance in different environments. Our results indicate that both genotypic (clones) and G x E interaction effects are important for the expression of coffee beverage quality. However, the clones BRS 3213, BRS 3210, and BRS 2299 had less prominent nuances, with lower potential for specialty coffee production.
Caracterização física e sensorial do café produzido nas condições topoclimáticas de Jesuitas, Paraná
(Editora da Universidade Estadual de Maringá - EDUEM, 2008-07) Molin, Roberto Natal Dal; Andreotti, Marcelo; Reis, André Rodrigues dos; Furlani Junior, Enes; Braga, Gilberto Costa; Scholz, Maria Brígida dos Santos
A variação das condições climáticas interfere na formação e na maturação dos frutos, alterando suas características intrínsecas, as quais podem permitir diferentes qualidades de bebida, com potencial de produção de café especial. O objetivo deste estudo foi verificar o efeito das condições ambientais e da prática de cultivo no aspecto físico e sua conseqüência na qualidade de bebida de cafés da região de Jesuítas, Estado do Paraná. Na mesma safra em que foi realizado este estudo (2002-2003), avaliou-se a qualidade de bebida de cafés paranaenses entre os produtores nos diversos municípios cafeeiros do Estado e verificou-se que 86% das amostras apresentaram bebida classificadas como apenas “mole” e “dura”, e 14% com bebida “riada/rio”. Os resultados obtidos permitiram concluir que as práticas adotadas pelos agricultores, colaboradores do presente estudo, refletiram positivamente na qualidade final da bebida, quando se comparou com os resultados de qualidade de bebida do Estado. As condições climáticas e as práticas de cultivo e de colheita de Jesuítas, Estado do Paraná, permitiram a obtenção de café encorpado e de baixa acidez, de qualidade comparável aos cafés de alta qualidade produzidos tanto em nível nacional quanto internacional.
Characterizing zinc use efficiency in varieties of Arabica coffee
(Editora da Universidade Estadual de Maringá - EDUEM, 2013-07) Pedrosa, Adriene Woods; Martinez, Hermínia Emilia Prieto; Cruz, Cosme Damião; DaMatta, Fábio Murilo; Clemente, Junia Maria; Neto, Ana Paula
Among micronutrients, zinc (Zn) is important for coffee tree cultivation, especially in the clayey acid soils of Brazil’s southeast region, where coffee production is an important activity. This study aimed to evaluate the Zn use efficiency of coffee tree varieties using two zinc concentrations. Seedlings of 11 varieties of coffee trees were grown in a greenhouse in nutrient solution containing either 0.0 or 6.0 μmol L-1 of Zn. After eight months, we evaluated the total biomass production, leaf biomass production, concentration of Zn in the plant organs, absorption efficiency, and Zn use efficiency. All characteristics were affected by the Zn concentration. The biomass production of apical leaves was most affected by the Zn treatments, with high variability for the studied varieties. The ‘IPR-103’ variety had the highest Zn use efficiency, and the ‘San Ramon’ and ‘San Bernardo’ varieties had the lowest Zn use efficiency. The ‘Rubi’ variety had a high and low Zn use efficiency when grown at 0.0 and 6.0 μmol L-1 of zinc, respectively. The ‘Oeiras’ variety had a low Zn use efficiency when cultivated at 6.0 μmol L -1 of zinc. The other varieties studied were moderately efficient in their use of zinc.
Comparison between grafting and cutting as vegetative propagation methods for conilon coffee plants
(Editora da Universidade Estadual de Maringá - EDUEM, 2013-10) Andrade Júnior, Saul de; Alexandre, Rodrigo Sobreira; Schmildt, Edilson Romais; Partelli, Fábio Luiz; Ferrão, Maria Amélia Gava; Mauri, Aldo Luiz
The purpose of this study was to assess the growth of conilon coffee tree plantlets that were propagated by grafting and cutting. The experiment was conducted at the plantlet production site of Incaper’s Experimental Farm in the city of Marilândia, Espírito Santo State. For grafting, plantlets derived from the seed propagation of Coffea canephora cv. Robusta Tropical (ENCAPER 8151) were used as rootstocks, and six clones of cv. Conilon Vitória (INCAPER 8142) were used as the grafts. The cutting was performed with six clones that were used for grafting. The experimental design consisted of randomized blocks of twelve treatments with five repetitions composed of twelve plantlets. On the hundred and fifth day, the averages of the variables were assessed and compared by the Scheffé test at a probability of 5%. The grafted plantlets were superior for almost all of the characteristics assessed, which suggests that it is possible to propagate conilon coffee trees.
Concentration and accumulation of micronutrients in robust coffee
(Editora da Universidade Estadual de Maringá - EDUEM, 2019) Dubberstein, Danielly; Partelli, Fabio Luiz; Espindula, Marcelo Curitiba; Dias, Jairo Rafael Machado
Knowledge on the dynamics of micronutrients in coffee tree assists nutritional diagnosis and fertilization management. Therefore, the objective of this study was to evaluate the concentration and accumulation of micronutrients in the leaves and fruits of Coffea canephora. The experiment was managed in crops propagated for 2.5 years in a split-plot-in-time scheme in which the main plots consisted of fertilized and not-fertilized plants, and the subplots stipulated the evaluation periods. The berries and leaves were collected every 28 days, starting from the first flowering to full maturity. The micronutrient content was determined by laboratory chemical analysis, and the accumulation of nutrients in the fruit (mg) was calculated by multiplying the dry matter of the berry (g) × nutrient concentration (mg kg−1). The results showed that fertilization infers the zinc concentration in the fruits and the concentration for manganese, iron and zinc in the leaves in the determined periods. Micronutrient accumulation curves followed the simple sigmoidal model, with accumulation increasing considerably as a function of fruit growth. Thus, fertilization based on micronutrients must be divided over stages with higher accumulation rates, considering the specific requirement of each nutrient.
Conilon coffee outturn index: a precise alternative for estimating grain yield
(Editora da Universidade Estadual de Maringá - EDUEM, 2022-03-09) Fialho, Gustavo Sessa; Fonseca, Aymbiré Francisco Almeida da; Ferrão, Maria Amélia Gava; Ferrão, Romário Gava; Olivoto, Tiago; Nardino, Maicon; Reis, Edvaldo Fialho dos; Sakiyama, Ney Sussumu
Coffee outturn can be defined as the ratio between the harvested coffee and its respective processed grains. This character is greatly influenced by genotypic and environmental effects, and in breeding programs your analysis is costly and time-consuming. In this sense, the use of an outturn index to estimate coffee yield on experimental plots is a desirable measure aiming at reducing resources and time in postharvest evaluations. Thus, the present study aimed to evaluate the accuracy of the use of an outturn index equal to 4.0, in the estimation of Conilon coffee grains production. This index indicates that four kilograms of harvested fruit would be needed to obtain one kilogram of processed grains. Based on the average of 157 genotypes conducted in three trials and four harvests, we evaluated the relationship between harvested fruits and processed grains (FcBe), the observed (OGY), and the estimated grain yield per plant (EGY) based on FcBe equal to 4.0 (an outturn index). Descriptive statistics, adequation test for EGY, and the coincidence of occurrence of genotypes observations relating to the top 20% of all observations of OGY and EGY. In the estimation of grain yield in Conilon, the use of FcBe equal to 4.0 showed high precision in the average of the analyzed trials. However, further studies should be conducted to elucidate the effects of climate variables on the yield of Conilon coffee, especially in atypical crop years. Thus, the use of an outturn index becomes interesting in cases where the number of genotypes to be evaluated is very large and a screening of the promising ones is desirable.
Control of coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) with botanical insecticides and mineral oils
(Editora da Universidade Estadual de Maringá - EDUEM, 2016-01) Celestino, Flávio Neves; Pratissoli, Dirceu; Machado, Lorena Contarini; Santos Junior, Hugo José Gonçalves dos; Queiroz, Vagner Tebaldi de; Mardgan, Leonardo
The objective of this study was to evaluate botanical oils, mineral oils and an insecticide that contained azadirachtin (ICA) for the control of Hypothenemus hampei, in addition to the effects of residual castor oil. We evaluated the effectiveness of the vegetable oils of canola, sunflower, corn, soybean and castor, two mineral oils (assist ® and naturol ® ), and the ICA for the control of H. hampei. The compounds were tested at a concentration of 3.0% (v v-1 ). The median lethal concentration (LC 50 ) was estimated with Probit analysis. The oil of castor bean and extract of castor bean cake were also evaluated at concentrations of 3.0% (v v -1 ) and 3.0% (m v-1 ), respectively. The mortality rates for H. hampei caused by the ICA and the castor oil were 40.8 and 53.7%, with LC 50 values of 6.71 and 3.49% (v v-1 ), respectively. In the castor oil, the methyl esters of the fatty acids were palmitic (1.10%), linoleic (4.50%), oleic (4.02%), stearic (0.50%) and ricinoleic acids (88.04%). The extract of the castor bean cake was not toxic to H. hampei. The persistence of the castor oil in the environment was low, and the cause of mortality for H. hampei was most likely the blockage of the spiracles, which prevented the insects from breathing.
Desempenho do manejo orgânico na nutrição e produtividade de lavoura cafeeira
(Editora da Universidade Estadual de Maringá - EDUEM, 2007-10) Theodoro, Vanessa Cristina de Almeida; Guimarães, Rubens José; Mendes, Antônio Nazareno Guimarães
Já existe um acervo de experiências práticas de transição agroecológica para a cultura do cafeeiro (Coffea arabica L.) em pequenas propriedades na região sul de Minas Gerais que inspiraram essa pesquisa. O experimento foi instalado em uma lavoura cafeeira (variedade Catuaí Amarelo, espaçamento 4,0 x 0,7 m e idade de 6 anos) localizada em Lavras, Estado de Minas Gerais. Após o primeiro ano de transição agroecológica, avaliaram- se os efeitos dos manejos orgânico e convencional na nutrição e produtividade da lavoura. Empregou-se o delineamento látice balanceado 4x4 em esquema fatorial 3x2x2 com cinco repetições mais quatro tratamentos adicionais. O manejo orgânico adotado é eficiente no fornecimento de N, P, K, S, Ca, Mg, Mn, B, Zn, Cu e Fe ao cafeeiro em produção. Os tratamentos de manejo orgânico apresentam produtividade similar à da testemunha convencional, devido à existência de reservas de nutrientes no solo.
Desenvolvimento de Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) em cafeeiros
(Editora da Universidade Estadual de Maringá - EDUEM, 2009-01) Santa-Cecília, Lenira Viana Costa; Correa, Lílian Roberta Batista; Souza, Brígida; Prado, Ernesto; Alcantra, Eliana
A cochonilha Planococcus citri (Risso, 1813) suga a seiva dos botões florais e frutos do cafeeiro, atacando as rosetas desde a floração até a colheita. Embora seja relatada há alguns anos na cafeicultura, são escassas as informações sobre o desenvolvimento dessa cochonilha em cafeeiros. Assim, o presente trabalho teve por objetivos avaliar alguns aspectos biológicos da fase ninfal de P. citri em plantas de café. Ovos dessa cochonilha foram retirados de uma criação em laboratório, isolados em placas de Petri contendo discos foliares de Coffea arabica L., das cultivares Acaiá Cerrado, Mundo Novo e Catuaí Vermelho e de C. canephora Pierre & Froenher, cultivar Apoatã. As placas foram mantidas em câmara climatizada a 25 ± 1°C, 70 ± 10% de umidade relativa e 12h de fotofase. Constatou-se que a cultivar Catuaí Vermelho foi a que proporcionou maior duração do período ninfal das fêmeas, porém, não foram constatadas diferenças na mortalidade. Essa cochonilha se desenvolveu satisfatoriamente em todas as cultivares de café estudadas e os resultados não mostraram diferenças claras de susceptibilidade.
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.
Effects of nitrogen and potassium on the chemical composition of coffee beans and on beverage quality
(Editora da Universidade Estadual de Maringá - EDUEM, 2015-07) Clemente, Junia Maria; Martinez, Herminia Emilia Prieto; Alves, Leonardo Corrêa; Finger, Fernando Luíz; Cecon, Paulo Roberto
The ratio of nitrogen (N) to potassium (K) is important in the production of specialty coffees because the relative amounts of N and K can either suppress the formation or increase the concentration of compounds that are essential to the flavor and aroma of specialty coffees. The purpose of this study was to evaluate the effect of different N:K ratios (w/w) and K doses on the cup quality of coffee. The concentrations of chemical compounds essentials to achieve good flavor and aroma, the N and K contents, and the caffeine contents of coffee leaves and beans were evaluated in this study. The N:K ratio and the K dose were found to be important factors in cup quality, the best quality corresponding to an N:K ratio of 1:1.56. The best cup quality was obtained from beans with greater PPO activity, caffeine, color index, and sugars and lower total tritatable acidity, pH, electrical conductivity and leached potassium. Keywords: Coffea arabica L., coffee, caffeine, fertilization.
Growth effects of water excess on coffee seedlings (Coffea arabica L.)
(Editora da Universidade Estadual de Maringá - EDUEM, 2014-04) Silveira, Helbert Rezende de Oliveira; Santos, Meline de Oliveira; Alves, Jose Donizeti; Souza, Kamila Rezende Dázio de; Andrade, Cinthia Aparecida; Alves, Raphaella Gomes Martins
The objective of the present study was to evaluate the interference of water excess in soil on the growth of young coffee plants of the Mundo Novo and Catuaí cultivars.Plants were subjected to the following three different substrate water availability conditions: control (well- watered), continuous substrate waterlogged, and intermittent substrate waterlogged. Several growth- related traits were evaluated over the course of 19 weeks. Based on the number and quality of the affected variables from all forms of analyses, the Catuaí cultivar showed greater sensitivity to waterlogging. Both cultivars exhibited growth inhibition in response to substrate waterlogging stress, which was exacerbated by premature leaf dropping.
Image analysis of coffee seeds submitted to the LERCAFE test
(Editora da Universidade Estadual de Maringá - EDUEM, 2016-07) Ribeiro, Bárbara Gomes; Abraão, Christovão Pereira; Nery, Marcela Carlota; Nacimento, Rodrigo Marques; Rezende, Juliana Costa; Fialho, Cíntia Maria Teixeira
The aim of this experiment was to quantify the stained areas of coffee seeds submitted to the LERCAFE test using image analysis. The seeds used were of the Catuaí Vermelho IAC 99 and Paradise cultivars. The physiological quality of the lots was assessed using germination tests, moisture content and a germination speed index. The LERCAFE test was conducted using seeds without parchment immersed in a solution of 3% sodium hypochlorite for 3 hours. Color photographs (RGB) with a resolution of 5 MPx were taken of each seed. The seeds were visually evaluated, and the functions generated from the analyses of the stained and non-stained regions were quantified by the Matlab R2009b program. Classification models were developed based on the Fisher Linear Discriminant Function and the evaluation of the adequacy of the models confusion matrix between the visual references and the classification generated by the linear functions. The image analysis for the creation of Fisher’s linear discriminant function in the development of classifiers for the coffee seeds submitted to the LERCAFE test is potentially efficient; however, it remains necessary to test other discriminant functions and quantification methodologies.
Inibição in vitro de fungos toxigênicos por Pichia sp. e Debaryomyces sp. isoladas de frutos de café (Coffea arabica)
(Editora da Universidade Estadual de Maringá - EDUEM, 2010-07) Ramos, Darlê Martins Barros; Silva, Cristina Ferreira; Batista, Luís Roberto; Schwan, Rosane Freitas
O café é um produto nacional com grande expressão para a economia brasileira. O uso excessivo de fungicidas tem levado a pesquisas sobre formas alternativas como o controle biológico. Objetivou-se avaliar o potencial antagônico de leveduras em co-cultivo com fungos filamentosos. Isolados das espécies Debaryomyces hansenii (UFLACF 889 e UFLACF 847) e Pichia anomala (UFLACF 710 e UFLACF 951) foram inoculados (10 3 a 10 6 células mL-1 ) com três espécies de fungos filamentosos, Aspergillus ochraceus, A. parasiticus e Penicillium roqueforti (10 3 a 10 6 esporos mL-1 ). A avaliação do crescimento micelial e a contagem de esporos foram realizadas durante 21 dias. Observou-se que o isolado UFLACF 889 apresentou, em média, maior efeito inibitório na produção de esporos de A. ochraceus (inibição de 82%) e P. roqueforti (74%). O isolado UFLACF 710 inibiu a produção de esporos, em média, 60 e 75,6% de A. ochraceus e P. roqueforti, respectivamente. A. parasiticus foi o fungo mais resistente à inibição pelas leveduras. O crescimento micelial não foi inibido pela presença da levedura em co-cultivo. Portanto, pode-se concluir que leveduras em cultivo pareado com fungos filamentosos são capazes de inibir a produção de esporos e, potencialmente, diminuir a disseminação destes fungos no processamento de café.
A irrigação do cafezal como alternativa econômica ao produtor
(Editora da Universidade Estadual de Maringá - EDUEM, 2010-04) Arêdes, Alan Figueiredo de; Pereira, Matheus Wemerson Gomes; Santos, Maurinho Luiz dos
Este trabalho objetivou verificar a viabilidade econômica da produção irrigada de café com pivô central em regiões com condições pluviométricas favoráveis à produção. Foram analisados quatro cenários para o nível de preços e três diferentes períodos de duração dos projetos de investimento. De acordo com os indicadores econômicos obtidos, a irrigação do cafezal com pivô central é economicamente superior à alternativa não-irrigada, sendo um fator condicionante para elevação da rentabilidade e diminuição do risco no cultivo do café.
Kinetic modeling of water sorption by roasted and ground coffee
(Editora da Universidade Estadual de Maringá - EDUEM, 2017-07) Baptestini, Fernanda Machado; Corrêa, Paulo Cesar; Oliveira, Gabriel Henrique Horta de; Cecon, Paulo Roberto; Soares, Nilda de Fátima Ferreira
The objective of this study was to model the kinetics of water sorption in roasted and ground coffee. Crude Arabica coffee beans with an initial moisture content of 0.1234 kg w kg dm-1 were used. These beans were roasted to a medium roast level (SCCA # 55) and ground at three particle sizes: coarse (1.19 mm), medium (0.84 mm) and fine (0.59 mm). To obtain the water sorption isotherms and the isosteric heat, different conditions of temperature and relative humidity were analyzed using the dynamic method at 25oC (0.50, 0.60, 0.70, and 0.80 of RH) and 30°C (0.30, 0.40, 0.50, 0.60, 0.70, and 0.80 of RH) and using the static method at 25oC (0.332 and 0.438 of RH). The GAB model best represented the hygroscopic equilibrium of roasted coffee at every particle size. Isosteric heat of sorption for the fine particle size increased with increments of equilibrium moisture content, indicating a strong bond energy between water molecules and the product components. The Gibbs free energy decreased with the increase in equilibrium moisture content and with temperature.