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URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11736

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Resultados da Pesquisa

Agora exibindo 1 - 10 de 19
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    Production, chemical composition, and quality of Arabic coffee subjected to copper doses
    (Pesquisa Agropecuária Brasileira, 2018-04) Martinez, Herminia Emilia Prieto; Lacerda, José Soares de; Clemente, Junia Maria; Silva Filho, Jaime Barros da; Pedrosa, Adriene Woods; Santos, Ricardo Henrique Silva; Cecon, Paulo Roberto
    The objective of this work was to evaluate the effect of copper on the chemical composition of coffee beans and on the quality of the beverage, relating both of them to the Cu leaf contents in coffee (Coffea arabica) plants. Coffee plants were grown in a hydroponic system containing 0.2, 0.4, 0.8, 1.6, and 3.2 μmol L-1 Cu until fruit setting. Coffee bean production was evaluated, and, after the cherries were dried, the following characteristics were determined: leaf Cu content; total titratable acidity; color index; electrical conductivity; leached K; polyphenol oxidase (PPO) activity; concentrations of caffeine, trigonelline, organic acids, total phenols, chlorogenic acids (3-CQA, 4-CQA, and 5-CQA), sucrose, glucose, arabinose, mannose, and galactose; and sensory quality of roasted beans. Cu increased bean yield, PPO activity, and the concentrations of organic acids, 3-CQA, sucrose, and arabinose. Total titratable acidity, total phenols, 4-CQA, and 5-CQA were reduced with increasing Cu doses. Leaf contents related to the maximum and minimum values of desirable and undesirable quality attributes ranged from 5.6 to 11.4 mg kg-1 Cu, respectively. Copper affects the production and chemical composition of coffee beans, and the attributes related to quality are maximized in plants with low leaf contents of the nutrient.
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    Alternative sources of potassium in coffee plants for better soil fertility, productivity, and beverage quality
    (Pesquisa Agropecuária Brasileira, 2018-12) Dias, Kaio Gonçalves de Lima; Guimarães, Paulo Tácito Gontijo; Carmo, Davi Lopes do; Reis, Thiago Henrique Pereira; Lacerda, Julian Junio de Jesus
    The objective of this work was to evaluate alternative sources of potassium for improving soil fertility and coffee productivity and beverage quality. The experiment was conducted in a coffee (Coffea arabica) crop, planted in an Oxisol area, in the municipality of Patrocínio, in the state of Minas Gerais, Brazil. The treatments consisted of the K sources TK47 and Super Greensand (SG) - both based on glauconite silicate mineral -, at the following doses: 0 kg ha-1 K2O (control); 42, 84, 168, and 336 kg ha-1 K2O from TK47; 618 kg ha-1 K2O from KCl; and 168 kg ha-1 K2O from SG. A randomized complete block design was used, with four replicates in each treatment. The experimental units consisted of three rows with ten plants each, using the eight central plants as the useful plot. Potassium fertilization with TK47 increased soil fertility, correcting soil acidity and elevating K+, P, and Ca2+ contents, effective cation exchange capacity, and Zn2+ and Fe2+ levels in the soil. Fertilization with 336 kg ha-1 K2O from TK47, in a single dose, provides grain yield and polyphenol oxidase activity similar to those of fertilization with 618 kg ha-1 K2O from KCl, in a split-dose, but a better sensory analysis of the resultant beverage.
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    Leaf morphoanatomy and biochemical variation on coffee cultivars under drift simulation of glyphosate
    (Planta Daninha, 2018) Reis, L. A. C.; Carvalho, F. P.; França, A. C.; Francino, D. M. T.; Pinto, N. A. V. D.; Freitas, A. F.
    The most widely used herbicide in coffee crop is glyphosate, it inhibits the biosynthesis of secondary metabolites, responsible for structures and substances of plant defense. This work aimed to evaluate the morphoanatomy, total phenols, flavonoids and caffeine in leaves of Arabica coffee submitted to different sub-doses of glyphosate. The treatments were combinations of three coffee cultivars (MGS Travessia, Oeiras MG 6851 and Catuaí IAC 144) and five sub-doses of glyphosate (0.0, 57.6, 115.2, 230.4 and 460.8 g a.e. ha-1). The total thickness of the leaf blade, thickness of adaxial and abaxial epidermis, palisade and spongy parenchyma, in addition to the total phenol, total flavonoids and caffeine were evaluated 30 days after spraying. Catuaí showed a reduction in the total leaf thickness, while the others cultivars had an increase. The thickness of adaxial and abaxial epidermis and palisade parenchyma was reduced, and the spongy parenchyma increased with increasing doses of glyphosate, regardless of the cultivars. There was an increase on the total phenols up to 115.2 g ha-1 glyphosate, and above this dose, the concentrations of phenols were reduced. The Travessia and Oeiras cultivars obtained a reduction of flavonoids up to 115.2 g ha-1; and above this dose, the concentration of flavonoids increased. The Catuaí cultivar showed an opposing behavior of the concentration of flavonoids. Oeiras and Catuaí showed a decrease of caffeine up to 115.2 g ha-1 and an increase at higher doses. Travessia showed an increase of caffeine in sub-doses above 115.2 g ha-1. The three cultivars showed a higher concentration of phenols in the palisade parenchyma after the application of glyphosate drift. Glyphosate reduces the thickness of the adaxial and abaxial epidermis and palisade parenchyma, and increases the thickness of spongy parenchyma. Doses of glyphosate above 230.4 g ha-1 result in the reduction of total phenols. The concentration of flavonoids and caffeine has varying effects with glyphosate application.
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    Population structure and genetic diversity of coffee progenies derived from Catuaí and Híbrido de Timor revealed by genome-wide SNP marker
    (Tree Genetics & Genomes, 2017-11-10) Sousa, Tiago Vieira; Caixeta, Eveline Teixeira; Alkimim, Emilly Ruas; Oliveira, Antonio Carlos Baião de; Pereira, Antonio Alves; Sakiyama, Ney Sussumu; Resende Júnior, Marcio Fernando Ribeiro de; Zambolim, Laércio
    The use of single nucleotide polymorphism (SNP) molecular markers has provided advances in selection methodologies used in breeding programs of different crops, reducing cost and time of cultivar release. Despite the great economic and social importance of Coffea arabica, studies with SNP markers are scarce and a small number of SNP are available for this species, when compared with other crops of agronomic importance. Thus, the objective of this study was to identify and validate SNP molecular markers for the species Coffea arabica and to introduce these markers to genetic breeding by means of an accurate analysis of the diversity and genetic structure of breeding populations of this species. After quality filtering, 11,187 SNP markers were selected from the coffee population obtained from crosses between the genotypes Catuaí and Híbrido de Timor. A great number of markers were distributed in the 11 chromosomes, within transcribed regions, and were used to estimate the genetic dissimilarity among the individuals of the breeding population. Dendrogram analysis and a Bayesian approach demonstrated the formation of two groups and the discrimination of all genotypes evaluated. The expressive number of SNP molecular markers distributed throughout C. arabica genome was efficient to discriminate all the accessions evaluated in the experiment, clustering them according to their genealogies. This work identified mixtures within the progenies. The genotyping data also provided detailed information about the parental genotypes and led to the identification of new candidate parents to be introduced to the breeding program. The study discussed population structure and its consequence in obtaining improved varieties of C. arabica.
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    Herbicide mixtures to control dayflowers and drift effect on coffee cultures
    (Planta Daninha, 2018-07-10) Freitas, N. M.; Freitas, F. C. L.; Furtado, I. F.; Teixeira, M. F. F.; Silva, V. F.
    The dayflower species Commelina benghalensis and C. diffusa are among the main weeds in coffee crops. The purpose of this study was to evaluate the efficacy of herbicides/herbicide mixtures in controlling dayflower species and to evaluate the possible intoxication of coffee cultures, as well as the effect of mixture interactions. Two experiments were conducted, the first one in a 12 x 2 factorial arrangement with 12 herbicides/mixtures (glyphosate, glyphosate + metsulfuron-methyl, glyphosate + flumioxazin, glyphosate + 2.4-D, glyphosate + oxyfluorfen, glyphosate + carfentrazone-ethyl, metsulfuron-methyl, flumioxazin, 2.4-D, oxyfluorfen and carfentrazone-ethyl) and two dayflower species (C. benghalensis and C. diffusa) and the second one, in a 6 x 2 + 1 factorial arrangement, with six herbicides/mixtures (glyphosate, glyphosate + metsulfuron-methyl, glyphosate + flumioxazin, glyphosate + 2.4-D, glyphosate + oxyfluorfen and glyphosate + carfentrazone-ethyl) and two application forms on coffee plants (reaching 1/3 of the coffee canopy and with a protected canopy), plus a control treatment without herbicides. There was tolerance variation within the dayflower species to the tested herbicides. Commelina benghalensis was controlled by glyphosate, 2.4-D, glyphosate + 2.4-D and glyphosate + metsulfuron-methyl, while C. diffusa was controlled by 2.4-D and glyphosate mixtures by + metsulfuron-methyl, glyphosate + oxyfluorfen and glyphosate + flumioxazin. The mixture glyphosate + 2.4-D is effective in controlling dayflower, but it caused intoxication and growth reduction of the coffee. There was antagonism in the mixture glyphosate + carfentrazone-ethyl in controlling both species, as well as for glyphosate + oxyfluorfen and glyphosate + flumioxazin for C. benghalensis.
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    Crescimento, produtividade e bienalidade do cafeeiro em função do espaçamento de cultivo
    (Pesquisa Agropecuária Brasileira, 2010-12-27) Sobreira, Fabricio Moreira; Pereira, Sérgio Parreiras; Bartholo, Gabriel Ferreira; Baliza, Danielle Pereira; Guimarães, Rubens José
    O objetivo deste trabalho foi avaliar as consequências da redução no espaçamento entre linhas e entre plantas na linha de plantio sobre o crescimento, a produtividade e a bienalidade de produção do cafeeiro (Coffea arabica). Utilizou-se o delineamento experimental de blocos ao acaso, com três repetições, em esquema fatorial 4x3. Foram utilizadas quatro distâncias entre as linhas (2,0, 2,5 3,0 e 3,5 m) e três distâncias entre as plantas na linha de plantio (0,50, 0,75 e 1,00 m), o que totalizou 12 tratamentos. A produtividade e a produção por planta foram avaliadas anualmente entre 1994 e 2001, e o crescimento foi avaliado em 2002. A redução no espaçamento entre as linhas e entre as plantas na linha de plantio aumenta a produtividade da lavoura cafeeira. Os espaçamentos entre as linhas e entre as plantas influenciam o crescimento e a arquitetura dos cafeeiros.
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    Water use efficiency by coffee arabica after glyphosate application
    (Acta Scientiarum. Agronomy, 2012-10-05) Carvalho, Felipe Paolinelli de; França, André Cabral; Souza, Bruna Pereira; Fialho, Cíntia Teixeira; Santos, José Barbosa; Silva, Antonio Alberto
    Many coffee growers apply glyphosate in directed applications, but some phytotoxicity has been noted. It is believed some herbicides can exert a direct or indirect negative effect on photosynthesis by reducing the metabolic rate in a way that can affect the water use efficiency. The objective of this study was to investigate the variables related to water use among coffee cultivars subjected to the application of glyphosate and the effects of each dose. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), Acaiá (MG-6851), Catucaí Amarelo (2SL) and Topázio (MG-1190), and three doses of glyphosate (0.0, 115.2 and 460.8 g acid equivalent ha-1), in a factorial 3 x 3 design. At 15 days after application, a reduction in stomatal conductance was observed, and smaller transpiration rate and water use efficiency were found in the fourth leaf at 15 days after application. There was a decrease in the transpiration rate at 45 DAA, with the Acaiá cultivar showing reductions with 115.2 g ha-1. There was transitory reduction in water use efficiency with glyphosate application, but can affect the growth and production. The Acaiá cultivar showed the highest tolerance to glyphosate because the water use efficiency after herbicide application.
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    Photosynthetic activity of coffee after application of glyphosate subdoses
    (Acta Scientiarum. Agronomy, 2012-03-20) Carvalho, Felipe Paolinelli de; França, André Cabral; Lemos, Vinícius Teixeira; Ferreira, Evander Alves; Santos, José Barbosa dos; Silva, Antonio Alberto da
    Farmers use non-selective herbicides, such as glyphosate, in directed applications to control weeds in coffee crops. Despite the precautions used during the application of herbicides, there are usually reports of poisoning in plantation areas. Moreover, it is fundamental to understand the effects of glyphosate on photosynthetic processes. The present study aimed to evaluate the characteristics associated with the photosynthetic activity in coffee cultivars subjected to doses of glyphosate. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), including Acaiá (MG-6851), Catucaí Amarelo (2 SL) and Topázio (MG-1190), and three subdoses of glyphosate (0.0, 115.2 and 460.8 g ha-1) in a 3 x 3 factorial scheme. Herbicide application led to reduced internal carbon, ratio between internal and environmental carbon, carbon consumption and photosynthetic rate at 15 days after application (DAA) in the fourth leaf. In the same leaf at 45 DAA, the carbon consumption of the cultivars was even less. Despite low carbon concentrations, no difference in consumption and photosynthetic rate was observed in the last leaf. Glyphosate caused metabolic damage with transitory effects on the photosynthetic rate; the Acaiá cultivar was the most tolerant. These transitory effects may result in irreversible and prolonged damage to crop growth.
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    MG Travessia: a coffee arabica cultivar productive and responsive to pruning
    (Crop Breeding and Applied Biotechnology, 2017-03-19) Carvalho, Gladyston Rodrigues; Bartholo, Gabriel Ferreira; Pereira, Antônio Alves; Rezende, Juliana Costa de; Botelho, Cesar Elias; Oliveira, Antônio Carlos Baião de; Silva, Felipe Lopes da
    This paper presents the results of progeny 1190-1170-2, which was recorded as ‘MGS Travessia’ and selected based on its performance in the state of Minas Gerais. The cultivar has short size, cylindrical canopy, high yield capacity, high vegetative vigor, very satisfactory husk/bean ratio, grain quality compatible to traditional cultivars, and is very responsive to skeleton pruning.
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    Crescimento de plantas de café em solos com resíduos de Picloram
    (Planta Daninha, 2011-10-27) D'Antonino, L.; França, A.C.; Silva, A.A.; Ferreira, L.R.; Silva, G.R
    Avaliou-se neste trabalho o crescimento de plantas de café cultivadas em um Latossolo Vermelho-Amarelo, com diferentes valores de pH e contaminado com resíduos de picloram. O experimento foi instalado em esquema fatorial (2 x 9), sendo o primeiro fator dois tipos de solo (Latossolo Vermelho-Amarelo pH 4,4 e pH 6,2) e o segundo, nove doses de picloram (0, 20, 40, 60, 80, 100, 120, 140 e 160 g ha1 ), no delineamento de blocos casualizados, com quatro repetições. Aos 60 e 120 dias após aplicação do herbicida (DAP), procedeu-se à avaliação visual de intoxicação das plantas, área foliar, pelo método não destrutivo, do diâmetro do caule, por paquímetro, e da altura das plantas, bem como à contagem do número de folhas completamente expandidas. Aos 120 DAP, fez-se a determinação da massa da matéria seca da parte aérea, do caule e das raízes, além do comprimento das raízes e volume radicular. Concluiu-se que plantas de café recém-transplantadas em solos com resíduos do picloram têm redução no seu crescimento, o que pode ter reflexo na futura produtividade da cultura. Caso sejam feitas operações visando ao aumento do pH desses solos, aumenta-se o risco da ocorrência de carryover.