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

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Resultados da Pesquisa

Agora exibindo 1 - 10 de 158
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    Pulverização hidropneumática usando equipamentos com e sem assistência eletrostática em cafeeiro conilon
    (Revista Engenharia na Agricultura, 2018-06-29) Vitória, Edney Leandro da; Rodrigues, Joice Paraguassú; Simon, Carla da Penha; Pereira, Raphaela Correia
    Objetivou-se avaliar a deposição de calda pulverizada e espectro de gotas no cafeeiro Conilon e as perdas proporcionadas com pulverizador hidropneumático, com e sem assistência eletrostática. O experimento foi instalado em delineamento de blocos ao acaso, com oito tratamentos (volumes de calda) e quatro repetições. Os volumes de calda com e sem assistência eletrostática, após diferirem em todas as características avaliadas no teste Skott-Knott, foram estudados separadamente. Para análise estatística da deposição, utilizou-se o esquema fatorial 4 (volumes de calda) x 2 (posições). Para análise do espectro de gotas, utilizou-se o esquema fatorial 4 (volumes de calda) x 3 (posições). Os volumes de calda pulverizados com a assistência eletrostática mostram resultados promissores para a tecnologia de aplicação dos produtos fitossanitários no cafeeiro Conilon, visto que a endoderiva foi reduzida em até 850%, a exoderiva em 323% e apresentou índices satisfatórios de cobertura e densidade de gotas.
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    Grain yield of coffee plants fertilized with different doses of 20-00-20 NPK formulation under rainfed conditions
    (Universidade Federal Rural do Semi-Árido, 2021-07-12) Torres, Josemar Dávila; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento De; Marcolan, Alaerto Luiz; Rocha, Rodrigo Barros
    Little is known about the management of high-yield clonal Coffea canephora in the Amazonian Region, mainly for nutritional aspects and cultivation system efficiency. This study aimed to evaluate the influence of different nitrogen and potassium fertilization rates on coffee grain yield and fertilizer use efficiency of C. canephora trees. An experiment was performed at an experimental field of the Embrapa Rondônia in Porto Velho (RO), Brazil. It was carried out in a split-plot scheme with six doses of 20-00-20 NPK formulation (0; 250; 500; 1,000; 2,000; and 3,000 kg ha-1) and three years of evaluation (2014, 2015, and 2016). An interaction between fertilizer dose and crop year was observed. Fertilizer doses showed an exponential behavior, with maximum yields of 51, 114, and 79 bags ha-1 at 3,000 kg ha-1 in the crop years of 2014, 2015, and 2016, respectively. Such a behavior impacted average and accumulated yields in the three harvest seasons. As for crop year effect within each fertilizer dose, the highest yield was reached in the second harvest after pruning for renewal of orthotropic stems. Moreover, fertilizer use efficiency by plants decreased exponentially, with the highest value at the lowest dose. Increasing doses of 20-00-20 formulation promoted an exponential increase in grain yield but decreased its use efficiency by C. canephora plants. This management also stimulated a strong biannual production.
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    Initial performance and genetic diversity of coffee trees cultivated under contrasting altitude conditions
    (Escola Superior de Agricultura "Luiz de Queiroz", 2023-08-14) Senra, João Felipe de Brites; Silva, Josimar Aleixo da; Ferreira, Adésio; Esposti, Marlon Dutra Degli; Ferrão, Maria Amélia Gava; Fassarella, Kamila Machado; Silva, Uliana Ribeiro; Milheiros, Idalina Sturião; Silva, Fernanda Gomes da
    This work evaluated the initial performance and genetic diversity of Coffea canephora genotypes cultivated in environments at contrasting altitudes. Fourteen morphophysiological traits and seven descriptors of the genus Coffea spp. of coffee trees cultivated at altitudes of 140 m and 700 m were evaluated. The design used was Federer’s augmented block in a 2 × 112 factorial scheme with six blocks. The first factor was the two environments, and the second was the 112 genotypes, with eight common treatments, being five conilon coffee clones and three arabica coffee cultivars. The data were analyzed by the method of REML/BLUP and genetic correlation method. Genetic diversity was evaluated by estimating the distance matrix, applying the Gower methodology followed by the clustering method by Tocher and UPGMA. The phenotypic means were higher in the environment at an altitude of 700 m, except for plant height, number of leaves, and canopy height (CH). Genotypic effects were significant for most traits except for leaf width, CH, unit leaf area, and total leaf area. A wide genetic diversity was verified, with distances varying from 0.037 to 0.593 for the pairs of genotypes 26 × 93 and T7 × 76, respectively. Most of the traits studied showed high genotypic correlation with the environment and expressive genetic correlation between the evaluated traits thereby demonstrating the possibility of indirect selection. There is an adaptation of conilon coffee genotypes to high altitudes and the possibility of developing a specific cultivar for the southern state of Espírito Santo.
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    Plant stem cell extract from Coffea canephora shows antioxidant, anti-inflammatory, and skin regenerative properties mediated by suppression of nuclear factor-κB
    (Associação Brasileira de Divulgação Científica, 2023-06-30) Guidoni, M.; Sousa Júnior, A.D. de; Aragão, V.P.M.; Silva, M.V. Toledo e; Barth, T.; Clarindo, W.R.; Endringer, D.C.; Fronza, M.
    Plant cell cultures have become a promising production platform of bioactive compounds for biomedical and cosmetic uses in the last decades. However, the success so far has been limited. The study aimed to evaluate the effectiveness of this unique biotechnology process to obtain a bioactive stem cell extract of Coffea canephora (SCECC) with antioxidant, anti-inflammatory, and regenerative properties. Total phenolic and flavonoid contents were determined in the SCECC by spectrophotometry. The chemical composition of the extracts was characterized by mass spectrometry. Antioxidant activity was evaluated using the colorimetric methods of free radical scavenging 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and the ferric reducing ability of plasma (FRAP). The anti-inflammatory activity was determined in lipopolysaccharide-stimulated RAW 264.7 macrophages through the production of superoxide anion (O2•-), nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and the activity of nuclear factor kappa B (NF-κB). Moreover, the ability of SCECC to stimulate the proliferation and migration of fibroblasts was assessed. Five compounds were tentatively identified, two flavonoids, two phenolic acids, and one sugar. High phenolic content and antioxidant activity were observed in the SCECC. SCECC promoted the proliferation and migration of fibroblasts and suppressed the pro-inflammatory mediators O2•-, NO, TNF-α, and IL-6 in a dose-dependent manner. Moreover, SCECC inhibited the NF-κB transcription factor. Therefore, we obtained evidence that the extract from C. canephora stem cells can be used as a natural agent against skin damage. Hence, it could be of interest in cosmetics for preventing skin aging.
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    Maturation and detachment force for mechanized harvesting of irrigated Conilon coffee in the Brazilian Cerrado
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2023-02-17) Santin, Mateus Rollemberg; Amabile, Renato Fernando; Malaquias, Juaci Vitória; Veiga, Adriano Delly; Brige, Felipe Augusto Alves; Sala, Pedro Ivo Aquino Leite
    The objective of this work was to determine the force required to detach fruits of Conilon coffee (Coffea canephora) genotypes in five maturation stages, to determinate the best stage for mechanized harvest, and to verify the possibility of future selections of genotypes adapted to mechanized harvesting. Harvests were carried out in the 2013/2014 crop season, and the detachment force was determined based for six fruits from each side of the crop row, collected randomly from the middle third of the plants. The detachment force curve was obtained for each cycle through logistic regression, using the R software. According to the duration of their cycle, the genotypes were divided into super early, early, medium, and semilate; the values of the coefficients of the detachment force curve equation were also obtained. There is genetic variability regarding fruit detachment force throughout the maturation cycle, which indicates the possibility of selecting genotypes adapted to mechanized harvesting. Fruit detachment force shows a considerable drop in the final stages of maturation. The raisin stage is the best for the mechanized harvest of irrigated Conilon coffee in the Cerrado.
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    Chemical attributes of an Oxisol with the addition of conilon coffee straw biochar
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2023) Alvarenga, Anarelly Costa; Passos, Renato Ribeiro; Andrade, Felipe Vaz; Mendonça, Eduardo de Sá; Rangel, Otacílio José Passos; Mosa, Lázaro Longue
    The objective of this work was to evaluate the effects of increasing rates of biochar produced with coffee straw, at two pyrolysis temperatures, on the chemical attributes of an Oxisol cultivated with conilon coffee (Coffea canephora) and on the nutrient content of coffee tree leaves. Treatments consisted of pyrolysis at two temperatures (350 and 600 °C) and of five biochar rates (0, 5, 10, 15, and 20 Mg ha-1). The following soil chemical attributes were evaluated: pH in water; P, K, Ca, Mg, Al, H+Al, Zn, Cu, Fe, and Mn contents; effective and potential cation exchange capacity (CEC); sum of bases (SB); base (V) and aluminium (m) saturation; and N, P, K, Ca, Mg, Zn, Cu, Fe, and Mn contents in the leaves. The biochar produced at 600°C, at rates of 10 and 15 Mg ha-1, promoted a greater K release into the soil. Regardless of temperature, coffee straw biochar increased K and P availability, sum of bases, base saturation, and CEC in the soil, but did not influence macro- and micronutrient contents in the leaves. The addition of increasing rates of coffee straw biochar in the soil increases P, K, Mg, SB, CEC, and V, regardless of pyrolysis temperature.
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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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    Chemical attributes of an Oxisol with the addition of conilon coffee straw biochar
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2023-05-19) Alvarenga, Anarelly Costa; Passos, Renato Ribeiro; Andrade, Felipe Vaz; Mendonça, Eduardo de Sá; Rangel, Otacílio José Passos; Mosa, Lázaro Longue
    The objective of this work was to evaluate the effects of increasing rates of biochar produced with coffee straw, at two pyrolysis temperatures, on the chemical attributes of an Oxisol cultivated with conilon coffee (Coffea canephora) and on the nutrient content of coffee tree leaves. Treatments consisted of pyrolysis at two temperatures (350 and 600°C) and of five biochar rates (0, 5, 10, 15, and 20 Mg ha-1). The following soil chemical attributes were evaluated: pH in water; P, K, Ca, Mg, Al, H+Al, Zn, Cu, Fe, and Mn contents; effective and potential cation exchange capacity (CEC); sum of bases (SB); base (V) and aluminium (m) saturation; and N, P, K, Ca, Mg, Zn, Cu, Fe, and Mn contents in the leaves. The biochar produced at 600°C, at rates of 10 and 15 Mg ha-1, promoted a greater K release into the soil. Regardless of temperature, coffee straw biochar increased K and P availability, sum of bases, base saturation, and CEC in the soil, but did not influence macro- and micronutrient contents in the leaves. The addition of increasing rates of coffee straw biochar in the soil increases P, K, Mg, SB, CEC, and V, regardless of pyrolysis temperature.
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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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    Repeatability and number of harvests required for selection in robusta coffee
    (Crop Breeding and Applied Biotechnology, 2004) Fonseca, Aymbiré Francisco Almeida da; Sediyama, Tocio; Cruz, Cosme Damião; Sakiyama, Ney Sussumu; Ferrão, Romário Gava; Ferrão, Maria Amélia Gava; Bragança, Scheilla Marina
    This study aimed to estimate the repeatability coefficient of the grain yield in Coffea canephora by three methods: to quantify the precision of the measurements; to predict the real value of an individual based on n evaluations; and to determine the number of phenotypic measures required in each plant to obtain an adequate precision level for an efficient discrimination of the genotypes. The coefficients of repeatability and determination were estimated based on four harvests of 80 genotypes. Highest estimates of the repeatability coefficient were obtained by the method of the principal components derived from the matrix of covariances, which expresses the correlation between each measurement pair. The prediction precision of the real individual value ranged from 65.32 to 81.59%, and remained practically unchanged from the sixth harvest on.