Biblioteca do Café

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1

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Agora exibindo 1 - 10 de 1074
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    Influência da alta concentração atmosférica de CO2 (↑[CO2 ]atm) × disponibilidade hídrica nas relações hídricas, trocas gasosas e acúmulo de carboidratos em Coffea arabica L.
    (Instituto de Pesquisas Ambientais, 2017) Sanches, Rodrigo Fazani Esteves; Catarino, Ingrid Cristina Araujo; Braga, Marcia Regina; Silva, Emerson Alves da
    (Influência da alta concentração atmosférica de CO2 (↑[CO2]atm) × disponibilidade hídrica nas relações hídricas, trocas gasosas e acúmulo de carboidratos em Coffea arabica L.). O objetivo deste trabalho foi avaliar a influência da ↑[CO2]atm nas relações hídricas, trocas gasosas e acúmulo de carboidratos em Coffea arabica. Cafeeiros foram cultivados sob diferentes [CO2]atm (400 e 760 ppm) e submetidos a dois regimes hídricos: rega diária e ciclos de suspensão de regas por 7, 10, 14 e 37 dias, seguidos de reidratação diária por 7 dias. Alterações significativas no potencial hídrico foram observadas nas plantas sob restrição hídrica a partir do 10º dia com recuperação total após a reidratação. As A foram maiores nos cafeeiros cultivados sob ↑[CO2]atm, mesmo sob restrição hídrica se comparadas aos demais tratamentos. Cafeeiros cultivados em ↑[CO2]atm e restrição hídrica não apresentaram diminuição nos teores de carboidratos em comparação aos cultivados sob ↑[CO2]atm e rega diária. Entretanto, em plantas sob 400 ppm CO2 e restrição hídrica, reduções significativas nos teores de açúcares, principalmente em folhas, foram observadas. Os teores de amido não alteraram em resposta aos tratamentos de CO2 e água. Aumento no nível de prolina foi observado no início da restrição hídrica retornando a níveis basais ao longo do experimento. Nossos resultados apontam para um efeito mitigador do ↑CO2 sobre o déficit hídrico por meio da manutenção no acúmulo de carboidratos das plantas de café.
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    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.
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    Effect of fruit load of the first coffee harvests on leaf gas exchange
    (Escola de Agronomia - UFG, 2021-01-14) Muñoz, Carlos Andres Unigarro; Bejarano, Lina Marcela Díaz; Acuña, José Ricardo
    Coffee production between the first and second harvest presents a difference in the fruit load with the plant age that could affect the leaf gas exchange. This research aimed to evaluate the effect of the increase in fruit load that occurs between the first and second harvest of the Coffea arabica L. production cycle on the measured gas exchange, at the two phenological stages of the fruit. The accessions E057, E318, E338 and E554 were used, as well as a completely randomized design, with three replications, using the accessions as treatments and the harvest measurements during the production cycle as the repeated measures. The variables yield per tree, number of fruits, absolute growth rates for height and stem, leaf area, leaf-to-fruit ratio and leaf gas exchange were measured across the phenological stages of fruit filling and ripening. The increase in the fruit load that occurs with age in the second harvest, if compared to the first harvest, showed a positive and significant effect on the net assimilation rate that was not expected for the obtained leaf-to-fruit ratios. Likewise, the differences in the assimilation rates were higher during the fruit-filling stage. This result suggests that the source-sink relationship may vary with the crop age and fruit phenological stage, and is not entirely depend on the leaf-to-fruit ratio.
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    Proposed diagrammatic scale to assess heat injury in coffee seedling canopy
    (Editora da Universidade Estadual de Maringá - EDUEM, 2023-04-28) Resende, Laís Sousa; Pozza, Edson Ampélio; Pereira, Renata Cristina Martins; Botrel, Élberis Pereira; Roteli, Karolaine de Cássia; Oliveira, Júlia Marques
    A diagrammatic scale with five levels (0, 0.1 - 2.0, 2.0 - 6.0, 6.0 - 10, and 10 - 14) was developed and evaluated to measure the symptoms of heat injury in a coffee seedling canopy. The scale was constructed to increase assessment efficiency and align the estimations more closely with the actual values. Two assessments with the diagrammatic scale and one without were conducted with an interval of seven days. The evaluators using the proposed scale presented estimates with better levels of precision, accuracy, reproducibility, and repeatability than those using a conventional method. The proposed diagrammatic scale was shown to provide a reliable estimate for assessing the symptoms of heat injury on the canopy of in Coffea arabica L. seedlings. Therefore, it is possible to standardize heat injury evaluation methods using this diagrammatic scale, allowing for data comparisons with different cultivars.
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    Morphophysiological responses of Conilon coffee matrix plants in a super-dense clonal garden
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2023-12-04) Silva, Josimar Aleixo da; Esposti, Marlon Dutra Degli; Senra, João Felipe de Brites; Comério, Marcone; Conceição, Amanda Oliveira da; Zacarias, Alex Justino; Milheiros, Idalina Sturião; Silva, Uliana Ribeiro; Silva, Fernanda Gomes da; Raimundo, Eduarda Gonçalves
    The objective of this work was to evaluate the morphophysiological responses and cutting production of clones of Conilon coffee (Coffea canephora) cultivars in a super-dense clonal garden in the state of Espírito Santo, Brazil. The super-dense clonal garden was built in 2019 using 39 clones: 9, 9, 9, and 12 of cultivars Centenária ES8132, Diamante ES8112, ES8122 (Jequitibá), and Marilândia ES8143, respectively. The experiment was carried out in a randomized complete block design, with three replicates. Cutting production and the following morphophysiological traits were evaluated at 9 and 18 months after planting: chlorophyll index, normalized difference vegetation index, plant height, canopy height, canopy diameter, number of shoots, number of viable cuttings, number of leaves, fresh leaf mass, and plant fresh and dry matter mass. The super-dense clonal garden caused different morphophysiological responses among the studied clones. In general, clones C2, C5, C6, C8, D1, D8, D9, J8, M2, M9, M10, and M12 showed a higher mean cutting production, whereas C4, J1, J4, M4, and M5 were the most sensitive to the super-dense regime. Under these conditions, it is recommended to increase the proportion of matrix plants of the latter clones.
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    Respostas fisiológicas e morfológicas de cultivares de café arábica à compactação do solo
    (Universidade Federal de Viçosa, 2021-05-31) Ramos, Elísia Gomes; Oliveira, Teógenes Senna de; Neves, Júlio Cesar Lima
    A compactação causada pela mecanização afeta a qualidade do solo e consequentemente o desenvolvimento das culturas, alterando a morfologia e fisiologia das mesmas. O objetivo deste trabalho foi avaliar o efeito de cinco graus de compactação do solo na fisiologia e morfologia de diferentes cultivares de café. O experimento foi realizado em casa de vegetação, com delineamento de blocos casualizados em arranjo fatorial 5 x 5, sendo cinco cultivares de café e cinco graus de compactação, com quatro repetições, totalizando 100 unidades experimentais. As cultivares utilizadas foram Arara, Catuaí Amarelo, Catuaí Vermelho, Mundo Novo e Paraíso, e os graus de compactação foram 68, 74, 80, 86 e 92%. No ensaio experimental foram avaliadas as seguintes variáveis: altura das plantas; diâmetro do ramo ortotrópico; número de folhas e de entre-nós; massa úmida e massa seca das raízes e da parte aérea; área foliar; comprimento, área de superfície e volume das raízes; diâmetro de raízes finas e grossas e trocas gasosas (condutância estomática, transpiração, fotossíntese e concentração interna de CO 2 ). Os resultados obtidos mostraram que os altos graus de compactação, acima de 80%, afetaram negativamente a maioria das variáveis; a cultivar Catuaí Vermelho apresentou pior desempenho independente do grau de compactação, enquanto o Arara e o Paraíso foram os mais resistentes ao solo compactado. A estrutura anatômica das raízes foi modificada com a compactação do solo, não sendo observado diferenças entre as cultivares. Palavras-chave: Coffea arabica L. Compactação. Morfologia. Fisiologia
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    Visual assessment of leaf area index in coffee (Coffea arabica L.) fields
    (Departamento de Engenharia Agrícola - UFCG, 2024-01-04) Castro-Pacheco, Sergio A.; González-Lutz, María I.; Araya-Alfaro, José M.; Vargas-Chinchilla, Mariano; Gutiérrez-Soto, Marco V.
    The application of leaf area index (LAI) in coffee crop management depends on the availability of methodologies for proper estimation. The objective of this study was to develop a methodology for the visual assessment of LAI in coffee fields and to establish a protocol for training, evaluation, and feedback for evaluators. Four rounds of LAI measurements were conducted using visual estimates, two instruments (LAI 2200-C and AccuPAR LP-80), and defoliation of coffee hedgerows in Poás, Costa Rica. In each round, five workers visually estimated the LAI values on two occasions separated by 15 days, and feedback reinforcement was provided to each worker at the end of each round. Visual assessments showed high repeatability and reproducibility and the estimates were adjusted to the linear regression model in most cases. Evaluators improved their capacity to visually assess the LAI throughout the rounds, as the value of R2increased consistently for most workers, with values as high as 0.87. Instrumentation evaluation of LAI produced R2values of 0.5-0.6, with significant underestimation bias. The performance of the different methods is discussed in the context of widely spaced hedgerows. The proposed visual methodology constitutes a statistically sound, rapid, simple, and reliable method for determining the LAI of coffee fields to aid in decision-making for crop management.
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    Morphophysiological responses of Conilon coffee matrix plants in a super-dense clonal garden
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2023-12-04) Silva, Josimar Aleixo da; Esposti, Marlon Dutra Degli; Senra, João Felipe de Brites; Comério, Marcone; Conceição, Amanda Oliveira da; Zacarias, Alex Justino; Milheiros, Idalina Sturião; Silva, Uliana Ribeiro; Silva, Fernanda Gomes da; Raimundo, Eduarda Gonçalves
    The objective of this work was to evaluate the morphophysiological responses and cutting production of clones of Conilon coffee (Coffea canephora) cultivars in a super-dense clonal garden in the state of Espírito Santo, Brazil. The super-dense clonal garden was built in 2019 using 39 clones: 9, 9, 9, and 12 of cultivars Centenária ES8132, Diamante ES8112, ES8122 (Jequitibá), and Marilândia ES8143, respectively. The experiment was carried out in a randomized complete block design, with three replicates. Cutting production and the following morphophysiological traits were evaluated at 9 and 18 months after planting: chlorophyll index, normalized difference vegetation index, plant height, canopy height, canopy diameter, number of shoots, number of viable cuttings, number of leaves, fresh leaf mass, and plant fresh and dry matter mass. The super-dense clonal garden caused different morphophysiological responses among the studied clones. In general, clones C2, C5, C6, C8, D1, D8, D9, J8, M2, M9, M10, and M12 showed a higher mean cutting production, whereas C4, J1, J4, M4, and M5 were the most sensitive to the super-dense regime. Under these conditions, it is recommended to increase the proportion of matrix plants of the latter clones.
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    Land Use and Changes in Soil Morphology and Physical-Chemical Properties in Southern Amazon
    (Sociedade Brasileira de Ciência do Solo, 2017) Melo, Vander Freitas; Orrutéa, Alessandro Góis; Motta, Antônio Carlos Vargas; Testoni, Samara Alves
    Many Amazonian farmers use the slash-and-burn method rather than fertilization for crop production. The aim of the present study was to evaluate changes in the morphological, physical, and chemical properties of naturally fertile Inceptisols after conversion from native forest to different uses in southern Amazonia, Brazil. Land covered by dense native forest (NF) was split into four areas of 1.0 ha each. Three areas were slashed and burned and then cultivated for 11 years with coffee (CO), secondary forest (SF), and pasture (PA). Four soil profiles were sampled in each treatment (four uses × four replicates). The mean value distribution of each physical and chemical analysis was determined for different depths, and standard error bars were placed to display significant differences among treatments. Results showed that morphology and physical properties were negatively affected after the establishment of PA and CO: a reduction in the thickness of the A horizon and in aggregate stability, a decrease in total porosity and macroporosity, and an increase in aggregate size and bulk density. Soil bulk density (SBD), geometric mean diameter of water-stable aggregates (GMD), and microporosity (SMi) were higher in soil under pasture as a consequence of more intense soil surface compaction. Native and secondary forests were the only treatments that showed granular structures in the A horizon. Significant differences between native forest and secondary forest were mainly found in the top soil layer for total porosity (STP) (NF>SF), macroporosity (SMa) (NF>SF), SBD (NF>SF) and GMD (SF>NF). Phosphorus contents in the A horizon increased from 6.2 to 21.5 mg kg-1 in PA and to 27.2 mg kg-1 in SF. Soil under coffee cultivation exhibited the lowest levels of Ca2+ and sum of bases in surface horizons. In all slash-and-burn areas there was a reduction in the C stock (Mg ha-1) of the A horizon: native forest 6.3, secondary forest 4.5, pasture 3.3, and coffee 3.1.
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    Physiological and morphological responses of Arabica coffee cultivars to soil compaction
    (Sociedade Brasileira de Ciência do Solo, 2023-12-22) Ramos, Elísia Gomes; Barros, Vanessa Maria de Souza; Miranda, José Danizete Brás; Silva, Laís Maria Rodrigues; Neves, Júlio Cesar Lima; Meira, Renata Maria Strozi Alves; Oliveira, Teogenes Senna de
    Compaction caused by mechanization affects soil quality and, consequently, the development of crops. This study aimed to evaluate the effect of different degrees of soil compaction on the physiology, morphology, and anatomy of different coffee cultivars in a controlled environment. The experiment was carried out in a greenhouse, with randomized block design in a 5 × 5 factorial arrangement, with five coffee cultivars (Arara, Catuaí Amarelo IAC 62, Catuaí Vermelho 144, MGS Paraíso 2 and Mundo Novo IAC 379-19) and five degrees of compaction (68, 74, 80, 86 and 92 %), with four repetitions, totaling 100 experimental units. The following variables were evaluated in the aboveground biomass: plant height, number of leaves, diameter of the orthotropic branch, fresh mass of leaves and stem, leaf area, gas exchange, and chlorophyll a and b index; in the roots: length, surface area, volume, diameter of fine and coarse roots, fresh and dry mass of roots, as well as anatomical characteristics. Results showed that soil with degrees of compaction above 80 % negatively affected the variables evaluated. Catuaí Vermelho 144 presented the worst performance regardless of the degree of compaction, while Arara and MGS Paraíso 2 showed the best performance under the evaluated compaction degrees. Anatomical structure of the roots was modified with soil compaction, and no differences were observed among cultivars.