Coffee Science - v.08, n.2, 2013
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/7822
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Item Drying kinetics of natural coffee for different temperatures and low relative humidity(Editora UFLA, 2013-04) Alves, Guilherme Euripedes; Isquierdo, Eder Pedroza; Borém, Flávio Meira; Siqueira, Valdiney Cambuy; Oliveira, Pedro Damasceno; Andrade, Ednilton TavaresFaced with the importance of the drying in the post-harvest phase of coffee and its influence in the final quality of the product, the current study had the aim of evaluating the kinetics of the drying in different temperatures of the drying air for a low temperature at dew point of fruits of arabic coffee (Coffea arabica) dry processed. The cherries were manually picked and submitted to hydraulic separation. After that, the fruits with initial water contents of 1.9 ± 0.1 kg.kg -1 (bs) were submitted to the drying process under three temperatures of dry bulb (35 °C, 40 °C e 45 °C) for the same temperature of dew point (2.6 °C) of the drying air. Seven mathematical models were adjusted to the experimental data to characterize the dry process of coffee cherries. Henderson and Pabis modified and Successive Residue models with two terms were the most adequate to describe the dry process, being the Henderson and Pabis modified model chosen, for being more simple. The elevation of the temperature of the dried bulb under the low temperature of dew point causes an increase of the effective diffusivity coefficient, the drying rate and reduces the time of drying. For the conditions which were studied, the effective diffusivity coefficient of water for coffee fruits varies between 1.908 e 3.721 x 10 -11 m2.s -1 . The activating energy for the liquid diffusion, described by the equation of Arrhenius, was of 52.89 kJ.mol -1 .Item Silicate slag combined with tebuconazole in management of brown eye spot in coffee(Editora UFLA, 2013-04) Lopes, Ueder Pedro; Zambolim, Laércio; Lopes, Uilton do Nascimento; Rios, Jonas Alberto; Duarte, Henrique Silva Silveira; Ribeiro Júnior, José IvoThe aim of this trial was to evaluate silicon absorption and the effect of silicate slag application combined with triazole fungicide in control of brown eye leaf spot under greenhouse conditions, using coffee seedlings of the cultivar Catuaí Vermelho 144. A completely randomized 5x2 experimental design was used, with and without application of the fungicide tebuconazole, with eight replications. The mixtures (M) used on the soil were defined as based on the liming needs of the soil: M 1 - 0% de silicated slag (slag) and 100% limestone (lim); M 2 - 25% slag and 75% lim; M 3 -50% slag and 50% lim; M 4 - 75% slag and 25% lim; M 5 - 100% slag, with or without application of the fungicide tebuconazole. The fungicide tebuconazole (0.5 g of a.i./L) was applied on coffee seedlings through five pair of leaves. Twenty-four hours after fungicide application, each coffee seedling was inoculated with a conidial suspension of 2.0 x 10 5 /mL. The severity and the defoliation caused by disease were evaluated every five days from 20 to 45 days after inoculation. With the severity and defoliation data, the area under the brown eye spot disease progress curve (AUCPBES) and the area under the defoliation curve (AUCPDESF) were calculated. The application of increasing doses of silicate slag on the soil did not reduce AUCPBES and AUCPDESF, and no increase in Si content in the root, stem or leaf was observed. Tebuconazole reduced AUCPBES and AUCPDESF.Item Comportamento agronômico de progênies e cultivares de cafeeiro com resistência específica à ferrugem(Editora UFLA, 2013-04) Costa, Joyce Cristina; Carvalho, Carlos Henrique de Siqueira; Matiello, José Braz; Almeida, Saulo Roque de; Carvalho, Samuel Pereira de; Baliza, Danielle PereiraObjetivando-se avaliar a produtividade e outras características agronômicas de progênies e cultivares de cafeeiro com resistência específica à ferrugem, foi conduzido um experimento na Fazenda Experimental do MAPA/Fundação Procafé, em Varginha, MG. Este foi instalado em janeiro de 2003, em blocos inteiramente casualizados, com 12 progênies e duas cultivares, cinco repetições e quatro plantas por parcela. Foram avaliadas as características de produtividade média dos grãos, estádio de maturação dos grãos e classificação por peneira. Os dados obtidos foram submetidos à análise de variância e quando houve efeito significativo dos tratamentos, as médias foram comparadas por meio do teste de Scott-Knott. Com o intuito de possibilitar a seleção indireta buscou-se conhecer o grau de associação das características em estudo, por meio das estimativas de correlação fenotípica entre as características avaliadas. E, posteriormente, para verificar a variabilidade existente entre as progênies foram estimadas as distâncias genéticas pelo método das Distâncias Generalizadas de Mahalanobis. Os resultados obtidos permitem verificar a existência de variação entre as progênies e cultivares quando as características são avaliadas de forma isolada. Não é indicado aplicar a seleção indireta nas características avaliadas, pois a produtividade média dos grãos não está fortemente associada às demais características. As progênies Arara planta 418 e Catucaí Amarelo 20/15 são indicadas para futuros cruzamentos, tendo em vista que esses materiais genéticos são mais produtivos que a testemunha Catuaí Amarelo IAC 66/69 e apresentam divergência genética entre si. Essas informações podem subsidiar os programas de melhoramento com finalidades específicas, ao possibilitar a escolha adequada de genitores.Item Field performance of coffee progenies and cultivars with specific resistance to rust(Editora UFLA, 2013-04) Costa, Joyce Cristina; Carvalho, Carlos Henrique de Siqueira; Matiello, José Braz; Almeida, Saulo Roque de; Carvalho, Samuel Pereira de; Baliza, Danielle PereiraThe aim of this research was to evaluate the yield and other agronomic characteristics of coffee progenies with specific resistance to rust. An experiment was carried out at the Experimental Farm of MAPA/Fundação Procafé (MAPA/ ProCoffee Foundation) in Varginha, MG, Brazil. The experiment was set up in January 2003 in a randomized complete block design with 12 progenies and two cultivars, five replicates and four plants per plot. The characteristics of average yield, maturation stage and screen analysis were asssessed. The data were subjected to analysis of variance and when there were significant effects from treatments, the means were compared by the Scott-Knott test. For the purpose of facilitating indirect selection, we sought to investigate the degree of association of the characteristics under study by means of the estimates of phenotypic correlation among the characteristics evaluated. Subsequently, genetic distances were estimated by the generalized Mahalanobis distance method to verify the variability among progenies. The results obtained allow us to verify the existence of variation among progenies and cultivars when the characteristics are evaluated separately. It is not recommended to apply indirect selection on the characteristics assessed because the average yield of coffee grains is not strongly associated with the other characteristics. The progenies Arara planta 418 and Catucaí Amarelo 20/15 are recommended for future crosses, considering that these genetic materials are more productive than the control Catuaí Amarelo IAC 66/69 and have genetic divergence. This information may help breeding programs for specific purposes upon enabling the appropriate choice of parents.Item Progresso da cercosporiose do cafeeiro sob diferentes manejos de irrigação e densidades de plantio(Editora UFLA, 2013-04) Paiva, Bernardo Reis Teixeira Lacerda; Souza, Paulo Estevão de; Scalco, Myriane Stella; Monteiro, Fernando PereiraA irrigação assim como o adensamento são práticas que alteram o microclima da cultura, as quais interferem na luminosidade, na temperatura e na umidade relativa do ar e, por consequência, na intensidade de doenças no cafeeiro. Por isso, quantificar a influência dessas práticas no progresso das doenças torna-se útil na tomada de decisão sobre o seu manejo adequado. Avaliou-se, no presente trabalho, o efeito de diferentes densidades de plantio e manejos de irrigação na incidência e na severidade da cercosporiose em cafeeiros adultos e relacionaram-se manejos de irrigação e densidades de plantio ao progresso da doença e enfolhamento da planta. O delineamento experimental foi em blocos ao acaso, com quatro repetições, em esquema de parcelas subdivididas. Os tratamentos foram constituídos por quatro densidades de plantio localizadas nas parcelas: 2.500 (4,0 x 1,0m), 3.333 (3,0 x 1,0m), 5.000 (2,0 x 1,0m) e 10.000 (2,0 x 0,5m) plantas.ha -1 e quatro manejos de irrigação (subparcelas), sendo: irrigação quando a tensão da água no solo atingiu valores próximos a 20kPa; irrigação quando a tensão da água no solo atingiu valores próximos a 60kPa; irrigação com a utilização de manejo do balanço hídrico climatológico (calculado por meio do software Irriplus) e uma testemunha não irrigada. Cada linha da subparcela foi constituída por 10 plantas, sendo consideradas como plantas úteis as seis centrais. Verificou-se que os manejos de irrigação influenciaram a incidência da cercosporiose e o enfolhamento, sendo que, em plantas não irrigadas a incidência da cercosporiose foi 30% maior, que os manejos irrigados. Quanto ao enfolhamento verificou-se que os tratamentos 20kPA e 60 kPA foram 9% e 5% maior comparado ao tratamento não irrigado. O aumento mais expressivo no enfolhamento foi obtido quando empregado o manejo do balanço hídrico com um valor 13% maior que a testemunha. Na análise de regressão da área abaixo da curva do progresso da severidade e incidência, o modelo quadrático obteve o melhor ajuste, tendo as equações y=0,000004x 2 -0,0137x+192,05 (R 2 =0,6901) e y=0,000014x 2 -0,4048x+5943,7 (R 2 =0,6086), respectivamente. O valor de mínima para área abaixo da curva do progresso da severidade foi obtido quando utilizada uma densidade de 7500 plantas por hectare aproximadamente. O valor de máxima foi obtido quando empregada a densidade de 1712,5 plantas por hectare. Para a área abaixo da curva do progresso da incidência foram obtidos resultados semelhantes. Os sistemas de plantios adensados, 10.000 plantas/ha e 5.000 plantas/ha, reduziram a incidência da cercosporiose em 35% e 31,5%, respectivamente. As densidades de plantio não interferiram no enfolhamento.Item Progress of cercospora leaf spot in coffee under different irrigation management systems and planting densities(Editora UFLA, 2013-04) Paiva, Bernardo Reis Teixeira Lacerda; Souza, Paulo Estevão de; Scalco, Myriane Stella; Monteiro, Fernando PereiraIrrigation and density are practices that change the microclimate of the crop and affect the incidence of light, temperature and relative humidity and, thus, the intensity of diseases in coffee. Therefore, quantifying the influence of these practices on disease progress is useful in making decisions regarding their appropriate management. This study evaluated the effect of different planting densities and irrigation management practices on the incidence and severity of Cercospora leaf spot on adult coffee plants, and irrigation and planting density practices were related to progress of the disease and plant leaf development. A randomized block experimental design was used with four replications in a split-plot arrangement. The treatments consisted of four planting densities located in the plots (conventional and dense): 2500 (4.0 x 1.0 m), 3333 (3.0 x 1.0 m), 5000 (2.0 x 1.0 m) and 10,000 (2.0 x 0.5 m) plants.ha -1 , and four irrigation management practices (split-plots), which were: irrigation when soil water tension reached values near 20kPa; irrigation when soil water tension reached values near 60 kPa; irrigation management using the climatic water balance (calculated by the software Irriplus); and a control without irrigation. Each row in the split-plot consisted of 10 plants, with the six center plants being considered as useful. It was found that irrigation management influences the incidence of Cercospora leaf spot and leaf formation; in non-irrigated plants the incidence of Cercospora leaf spot was 30% greater than in the irrigated managements. The foliage had values close to 1000 as the area under the disease progress curve. In regression analysis of the area under the severity and incidence progress curve, the quadratic model gave the best fit, with the following equations: y=0.000004x 2 -0.0137x+192.05 (R 2 =0.6901) and y=0.000014x2-0.4048x+5943.7 (R 2 =0.6086), respectively. The minimum value of the area under the severity progress curve was obtained when using a density of approximately 7500 plants per hectare. The maximum value was obtained when using the density of 1712.5 plants per hectare. For the area under the incidence progress curve, similar results were obtained. High planting density systems of 10,000 plants/ha and 5,000 plants/ha reduced the incidence of Cercospora leaf spot by 35% and 31.5%, respectively. Planting density did not affect leaf development.Item Modifications in the metabolism of carbohydrates in (Coffea arabica L. cv. siriema) seedlings under drought conditions(Editora UFLA, 2013-04) Brum, Christiane Noronha Fernandes; Melo, Emanuelle Ferreira; Barquero, Luis Orlando Barboza; Alves, José Donizeti; Chalfun-Júnior, AntonioUnderstanding what mechanisms are involved in drought response in coffee plants will generate relevant information to assist breeding and/or genetic engineering to obtain new commercial varieties with drought tolerance. This research aimed at studying the effects of drought on leaf water potential, carbohydrate concentrations, and sucrose synthase and invertase activity in coffee seedlings (Coffea arabica Siriema), originating from a natural cross between C. racemosa and C. arabica Blue Mountain (Carvalho et al., 2008). Seedlings were grown in a greenhouse under non-irrigated and daily irrigated conditions. Plants were evaluated every three days until they reached the permanent wilting point or, at most. 30 days after withholding water. In addition, plants under different drought conditions (as of 30 days) were irrigated and evaluated 24 and 48 hours after water application. The non-irrigated treatment prompted a significant reduction in leaf water potential, whereas re-irrigation promoted partial recovery of plant water potential. There was a significant increase in the levels of total soluble sugars and reducing sugars, both in the leaves and roots of the non-irrigated plants. The re-irrigated plants behaved like the non-irrigated plants; however, lower levels of sugars were detected in these samples. The leaves and roots of the non- irrigated plants also showed a significant reduction in starch levels. The activity of sucrose synthase and invertase, neutral and acid enzymes, increased as a result of water stress.Item Morphological plasticity of three coffee cultivars under light gradient(Editora UFLA, 2013-04) César, Fábio Ricardo Coutinho Fontes; Matsumoto, Sylvana Naomi; Viana, Anselmo Eloy Silveira; Bonfim, Joice AndradeThe aim of this study was to fill in gaps in knowledge regarding the interaction among shading systems, stages of development and cultivars on the initial growth of coffee plantlets, with due attention to adequate mathematical models, and to allow interpretations in light of currently emerging knowledge on this theme. The cultivars Catuaí (IAC 144), Catucaí 2SL, and Acauã were subjected to levels of light restriction of 30%, 50%, and 70%, and to full sunlight. The experiment was conducted from January to June 2007 in the experimental field at the Universidade Estadual do Sudoeste da Bahia – UESB, Vitória da Conquista, the state of Bahia, Brazil. In each trial defined by level of light restriction, a randomized block experimental design was used with five replicates, and the treatments were arranged in a split-plot design in which the main plot consisted of cultivars and the assessment times constituted the split-plots. Each experimental unit consisted of 12 plants. Vegetative development assessments began 30 days after emergence and were conducted at 15-day intervals until 90 days. The light restriction levels and assessment periods, as well as the interaction between those factors, affected all the growth characteristics evaluated. With the exception of stem diameter, all other growth parameters had similar behavior in relation to the number of days after emergence and levels of light restriction. In general, the morphological changes in the initial growth of the coffee plantlet were more intense under light restriction values from 30% to 50%, and Catucaí 2SL presented greater development in comparison to Catuaí (IAC 144) and Acauã.Item Qualidade do café arborizado e a pleno sol, em manejo pós-colheita no sudoeste da Bahia(Editora UFLA, 2013-04) Souza, Antonio Jackson de Jesus; Matsumoto, Sylvana Naomi; Malta, Marcelo Ribeiro; Guimarães, Rubens JoséPara caracterizar aspectos relacionados à qualidade química e física do café arábica, cultivado sob arborização e a pleno sol, com manejo pós-colheita por via úmida e seca, foi desenvolvido o presente estudo. O delineamento experimental utilizado foi em blocos casualisados, no esquema fatorial 2 x 2 (duas formas de cultivo – a pleno sol e arborizado com grevílea e de duas formas de processamento – via seca e via úmida), constituídos de cinco blocos, totalizando 20 parcelas. A parcela foi composta, após colheita e manejo pós-colheita, por volume de 10 litros de frutos de acordo com o tratamento. Na colheita, para cada forma de cultivo, foi avaliado a massa úmida, seca e teor de umidade em 100 frutos. Na pós secagem foi determinada a massa seca do café e massa do café beneficiado. Para a determinação da qualidade do café foram realizadas análises físicas e químicas. Observou-se efeito da interação manejo pós-colheita e sistema de cultivo, nas características massa úmida e massa seca de café, rendimento do café e acidez titulável total. O processamento por via úmida incrementa o rendimento do fruto e a massa do café beneficiado. Cafés arborizados apresentam menor número de defeitos, maiores teor de açúcares não redutores e açúcares totais. A associação de árvores aos cafezais contribui para melhorar os aspectos físicos e químicos dos grãos. A utilização do manejo pós-colheita por via úmida, melhora a qualidade física do café.Item Quality of forested and full sun coffee, in post-harvest management in southwestern Bahia(Editora UFLA, 2013-04) Souza, Antonio Jackson de Jesus; Matsumoto, Sylvana Naomi; Malta, Marcelo Ribeiro; Guimarães, Rubens JoséTo summarize aspects related to the physicochemical quality of Coffea arábica, cultivated under afforestation and full sun, with both wet and dry post-harvest management, was carried on the present study. The experimental delimitation used was through randomized blocks, in the factorial design 2 x 2 (two cultivation forms – full sun and forested with grevillea and two forms of processing – dry and wet ways), formed of five blocks, totaling 20 portions. The portion was composed, after harvesting and post-harvesting management, by a volume of 10 litres of beans according to the treatment. During harvesting, for each form of cultivation, were evaluated the humid mass, dry mass and the humidity levels in 100 beans. During afterdrying were determined the coffee beans’ dry mass and the improved coffee mass. To determine the quality of the coffee, physicochemical analyses were performed. Effects of post-harvest management and cultivation systems were observed in the humid and dry coffee mass characteristics, as well as coffee yield and total titratable acidity. The wet processing increases bean yield and improved coffee mass. Forested coffee presented smaller number of defects, larger reducers and total sugars. The association of trees to the coffee plantations contributed to increase the physicochemical aspects of the beans. The using of wet post-harvesting management increases the physical quality of the coffee.