Periódicos

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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Resultados da Pesquisa

Agora exibindo 1 - 10 de 35
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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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    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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    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.
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    Reduction of frost damage to coffee trees under agroforestry systems
    (Universidade Federal de Lavras, 2023-10-03) Santoro, Patricia Helena; Morais, Heverly; Kitzberger, Cintia Sorane Good
    Frosts affect coffee production in Brazil, with effects on commodity prices around the world. Agroforestry systems are strategies to reduce the effects of frost on coffee trees. To date, this study has evaluated the largest number of tree species in coffee tree AFSs in Brazil in the same experiment. The objective was to identify tree species that can protect coffee trees against frost damage in agroforestry systems. The study was conducted in Londrina, Paraná, Brazil. Each treatment consisted of coffee trees associated with one of the following tree species: Moringa oleifera, Croton floribundus, Trema micrantha, Gliricidia sepium, Senna macranthera, Heliocarpus popayanensis, and Mimosa scabrella, as well as a control of coffee trees in monoculture. The experimental area was affected by frost that damaged the coffee plants fifteen months after planting. Immediately thereafter, the dendrometric characteristics of the trees were evaluated. After 30 days, the defoliation and mortality of the trees were evaluated. The phytometric characteristics of the coffee trees were evaluated 12 months after the frosts. Six of the seven tree species were evaluated for the first time for their ability to protect coffee trees against frost. Even at an early stage of development, T. micrantha and H. popayanensis provided increased protection of coffee trees, reducing the defoliation and mortality of coffee trees. The main protective factor was the canopy area of these species, which provided a high rate of tree cover. The development of coffee trees after frosts was favoured by the shading of the species, with the exception of M. scabrella. The AFSs with T. micrantha and H. popayanensis constitute an alternative that allows the mitigation of frost damage to coffee plants in regions prone to this climatic stress, reducing defoliation and mortality.
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    Coffee plant diseases affected by nutritional balance
    (Universidade Federal de Lavras, 2023-05-02) Pozza, Edson Ampélio; Pozza, Adélia Aziz Alexandre
    In recent years, sustainability has become a priority in agricultural production programs throughout Brazilian territory due to the need to ensure food security and environmental quality. Diseases continue to be a factor limiting sustainable agricultural production, due to the great need for chemical defenses for their control. Thus, it is indispensable to make use of alternative management techniques to reduce the use of such chemical defenses and to increase resistance of plants to diseases. It is known that mineral nutrients affect plant resistance to diseases, and effective physical and biochemical response of plants to pathogens is determined by adequate concentrations of mineral elements in the plant tissues. This review presents the most recent information related to the mode of action of the nutrients in the host-pathogen interaction and individual action in the control of plant diseases with the use of essential nutrients, as well as other elements considered beneficial, such as Si. It also reports on the use of some of these mineral nutrients in control of the main diseases of the coffee plant that occur in Brazil, especially rust, cercosporiosis or brown eye spot, phoma leaf spot, and bacterial blight. In addition, contradictory and satisfactory results are found in the literature on the use of mineral nutrients in control of different diseases, including coffee diseases.
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    Mapping of coffee land zoning based on sensory attributes of wine coffee
    (Universidade Federal de Lavras, 2023-01-20) Chairuddin, Zulkarnain; Laban, Sartika; Iksan, Muh.; Khaerunnisa, Khaerunnisa; Suhardjo, Suhardjo; Hock, Tan Khim
    The primary aimed of this study is to carry out land zoning of Arabica coffee area based on the characteristics of organoleptic sensory attributes with the optimal taste of coffee wine at different levels of altitudes. The study was conducted on the hillsides of Mount Bawakaraeng Lompobattang, South Sulawesi Province which has Arabica coffee plants at different altitudes, namely, 1000-1200 m.asl (A), 1200-1400 m.asl (B), 1400-1600 m.asl (C), and 1600-1800 m.asl (D). Quality tests of coffee beans and organoleptic sensory attribute taste tests were carried out including fragrance or aroma, flavor, aftertaste, acidity, body, uniformity, balance, clean cup, sweetness, overall, and taint or defect. The results of the study showed that the coffee beans were classified as quality 1 with large bean size; while the characteristics of uniformity, clean cup, and sweetness are the basic or essential characteristics of the coffee beans tested in this study because they showed the highest score of 10 and this score is consistent for all levels of altitudes. The results of compiling organoleptic sensory attribute data and satellite imagery analysis were used for mapping potential coffee fields with Specialty Grade, covering area of 20,025.54 ha or equal to 2.00% of the research area of 1,011,693 ha. In addition, coffee land zones can also be mapped with the level of coffee wine taste based on the distribution pattern of dominant organoleptic sensory attributes at different altitude. The order of the optimal level of coffee wine taste can be written as the land zoning, as follows: D > B > C > A. The land zoning D covers an area of 3,351.60 ha; B 5,738.53 ha; C 4,381.27 ha; and A 3,552.10 ha. Overall, it can be concluded that the taste of wine coffee tends to be better or optimal as the level of altitude increases.