Navegando por Autor "Clemente, Junia Maria"
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Item Boron, copper and zinc effects on photosynthesis, enzymatic activity, nutritional status, production, chemical composition and cup quality of coffee(Universidade Federal de Viçosa, 2014-07-16) Clemente, Junia Maria; Finger, Fernando Luiz; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783681Y0; Neves, Yonara Poltronieri; http://lattes.cnpq.br/6151512891086957; Martinez, Hermínia Emília Prieto; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788276P4; http://lattes.cnpq.br/8345230562555588; Neves, Júlio César Lima; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783076D4; Santos, Ricardo Henrique Silva; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4723069A2; Jifon, John Lonfover; Pereira, Adriana Farah de Miranda; http://lattes.cnpq.br/8889277811105841A ordem de exigência de micronutrientes pelo cafeeiro é Fe>Mn>B>Zn>Cu>Mo, o que permite inferir que os maiores problemas estão relacionados ao B, Cu e Zn, uma vez que os solos brasileiros apresentam teores elevados de Fe e Mn. As formas usuais de fornecimento do B, Cu e Zn a cafeeiros são via solo ou via pulverização foliar, porém, ambas as formas possuem desvantagens, além disso, a literatura é bastante rica quanto às melhores fontes e doses para que sejam obtidas boas produtividade, no entanto, pou- co ainda é conhecido sobre seus efeitos na qualidade da bebida. Assim, objetivou-se com esse trabalho verificar a viabilidade da suplementação do B, Cu e Zn via inserção de comprimidos na haste ortotrópica do Coffea arabica L., bem como, avaliar a resposta do cafeeiro em termos de produtividade e qualidade dos grãos. Foram executados três experimentos em campo sob delineamento em blocos casualizados com 5 repetições. Para avaliar o efeito do B foram aplicados os tratamentos sem o fornecimento de B, pulverização foliar contendo ácido bórico (0,4%) e inserção de comprimidos contendo sais de B, B+Cu, B+Zn e B+Cu+Zn; para avaliar o efeito do Cu foram aplicados os tra- tamentos sem o fornecimento de Cu, pulverização foliar contendo sulfato de cobre (0,4%) e inserção de comprimidos contendo sais de Cu, B+Cu, Cu+Zn e B+Cu+Zn e para avaliar o efeito do Zn foram aplicados os tratamentos sem o fornecimento de Zn, pulverização foliar contendo sulfato de zinco (0,4%) e inserção de comprimidos conten- do sais de Zn, B+Zn, Cu+Zn e B+Cu+Zn. Adicionalmente, foi executado um experi- mento em casa de vegetação com objetivo de determinar as concentrações de B, Cu e Zn que se relacionam com a máxima eficiência fotossintética e relacioná-las também às atividades da polifenoloxidase e superóxido dismutase. O experimento foi executado usando-se vasos de 50 L contendo areia lavada e plantas de café cultivadas nessa condi- ção durante três anos, em sistema hidropônico, sob delineamento inteiramente casuali- zado com três repetições. As doses de 0.4, 0.8, 1.6 e 3.2 μmol/L de Cu; de 1.0, 2.0, 3.0 e 4.0 μmol/L de Zn e 10, 20, 30 e 40 μmol/L de B constituíram os fatores em estudo. A inserção de comprimidos no tronco, contendo B, Cu e Zn embora necessite de ajustes ivquanto a composição e doses é eficaz no fornecimento dos nutrientes às plantas e é mais regular que a pulverização foliar. O B, Cu e Zn fornecidos via pulverização foliar ou inserção de comprimidos na base do tronco influenciaram a qualidade dos grãos de café, caracterizada pelos teores de cafeína, trigonelina, sacarose, glicose, arabinose, manose, ácido 3-cafeoilquínico, ácido 5- cafeoilquínico, atividade da polifenoloxidase e compos- tos fenólicos totais. Apenas o Cu influenciou a qualidade da bebida avaliada pela prova de xícara. O Cu e Zn fornecidos via inserção de comprimidos foi equivalente à pulveri- zação foliar tanto em produção quanto em qualidade. Com base nos resultados do expe- rimento adicional pode-se dizer que a atividade da polifenoloxidase pode ser um indica- dor do estado nutricional das plantas em B e Cu. A atividade da superóxido dismutase é proporcional aos teores foliares de Cu e Zn e a atividade fotossintética é ótima quando os teores foliares de B e Cu encontram-se dentro da faixa de suficiência previamente estabelecida, resultando também em máxima atividade da polifenoloxidase.Item Carrot yield and recovery efficiency of nitrogen, phosphorus and potassium(Revista Caatinga, 2016-10) Assunção, Natália Silva; Clemente, Junia Maria; Aquino, Leonardo Angelo De; Dezordi, Luciel Rauni; Santos, Luiz Paulo Dornelas DosThe objective of this work was to evaluate the carrot crop recovery efficiency of nitrogen, phosphorus and potassium from fertilizers. Two experiments were conducted in an experimental area in Rio Paranaiba - MG. The cultivar ("Juliana‟) was sown during the summer period and the cultivar "Nayarit‟ during the winter period. In both experiments, the treatments consisted of six fertilization combinations of N, P2O, K2O (kg ha-1): fertilization without N (0-500-450), without P (100-0-450), without K (100-500-0), standard (100-500-450), higher than standard (100-700-600) and lower than standard (100-300-300). The harvest was carried out when most of the roots presented commercial standard well accepted by the consumers. The fresh and dry matter of roots and leaves were quantified, and the yield was calculated based on the fresh matter. The analysis of N, P and K contents in leaves and roots were carried out by harvest time, and the nutrients absorption and exportation were determined based on these contents and on the dry matter of roots and leaves. N, P and K omissions reduced the yield of the cultivar "Juliana‟. For the cultivar "Nayarit‟, only P omission reduced and P and K fertilizations increased the yield. The cultivar "Nayarity‟, which is more productive than "Juliana", absorbed more quantities of N, P and K. Carrot recovery efficiency of nitrogen, phosphorus and potassium is low.Item Characterizing zinc use efficiency in varieties of Arabica coffee(Acta Scientiarum. Agronomy, 2013-07) Martinez, Hermínia Emilia Prieto; Cruz, Cosme Damião; DaMatta, Fábio Murilo; Clemente, Junia Maria; Pedrosa, Adriene Woods; Paula Neto, AnaAmong micronutrients, zinc (Zn) is important for coffee tree cultivation, especially in the clayey acid soils of Brazil's southeast region, where coffee production is an important activity. This study aimed to evaluate the Zn use efficiency of coffee tree varieties using two zinc concentrations. Seedlings of 11 varieties of coffee trees were grown in a greenhouse in nutrient solution containing either 0.0 or 6.0 µmol L-1 of Zn. After eight months, we evaluated the total biomass production, leaf biomass production, concentration of Zn in the plant organs, absorption efficiency, and Zn use efficiency. All characteristics were affected by the Zn concentration. The biomass production of apical leaves was most affected by the Zn treatments, with high variability for the studied varieties. The 'IPR-103' variety had the highest Zn use efficiency, and the 'San Ramon' and 'San Bernardo' varieties had the lowest Zn use efficiency. The 'Rubi' variety had a high and low Zn use efficiency when grown at 0.0 and 6.0 µmol L-1 of zinc, respectively. The 'Oeiras' variety had a low Zn use efficiency when cultivated at 6.0 µmol L-1 of zinc. The other varieties studied were moderately efficient in their use of zinc.Item Diagnosis of the nutritional status of garlic crops(Revista Brasileira de Ciência do Solo, 2015-11-06) Cunha, Mário Lúcio Pereira; Aquino, Leonardo Angelo; Novais, Roberto Ferreira; Clemente, Junia Maria; Aquino, Priscila Maria de; Oliveira, Thaisa FernandaUnivariate methods for diagnosing nutritional status such as the sufficiency range and the critical level for garlic crops are very susceptible to the effects of dilution and accumulation of nutrients. Therefore, this study aimed to establish bivariate and multivariate norms for this crop using the Diagnosis and Recommendation Integrated System (DRIS) and Nutritional Composition Diagnosis (CND), respectively. The criteria used were nutritional status and the sufficiency range, and then the diagnoses were compared. The study was performed in the region of Alto Paranaíba, MG, Brazil, during the crop seasons 2012 and 2013. Samples comprised 99 commercial fields of garlic, cultivated with the cultivar “Ito” and mostly established in Latossolo Vermelho-Amarelo Distrófico (Oxisol). Copper and K were the nutrients with the highest number of fields diagnosed as limiting by lack (LF) and limiting by excess (LE), respectively. The DRIS method presented greater tendency to diagnose LF, while the CND tended towards LE. The sufficiency range of both methods presented narrow ranges in relation to those suggested by the literature. Moreover, all ranges produced by the CND method provided narrower ranges than the DRIS method. The CND method showed better performance than DRIS in distinguishing crop yield covered by different diagnoses. Turning to the criterion of evaluation, the study found that nutritional status gave a better performance than sufficiency range in terms of distinguishing diagnoses regarding yield.Item Diagnostic methods to assess the nutritional status of the carrot crop(Revista Brasileira de Ciência do Solo, 2015-09-25) Dezordi, Luciel Rauni; Aquino, Leonardo Angelo de; Aquino, Rosiane Filomena Batista de Almeida; Clemente, Junia Maria; Assunção, Natália SilvaLeaf analysis may identify nutrient deficiency or excess in plant tissue. The aim of this study was to determine reference values and generate nutritional diagnosis from the results of leaf analysis of the carrot crop (Daucus carota L.) by the methods of Critical Level, Sufficiency Range, Diagnosis and Recommendation Integrated System, and Compositional Nutrient Diagnosis. Contents of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn were determined in 210 carrot fields in the 2012 and 2013 crop seasons in the Alto Paranaíba region, MG, Brazil. The whole plant shoot was sampled at harvest time to generate reference values for diagnosis. The high yielding subpopulation showed yield higher than 87.8 Mg ha-1. The four diagnostic methods generated similar reference values of nutrients, but different from those found in the literature. Leaf diagnosis through nutrient content in the shoot at harvest time indicated Mn as the most limiting nutrient for growing carrot, followed by Mg, K, and Ca.Item DRIS indices in three phenological stages of the carrot crop(Pesquisa Agropecuária Tropical, 2017-02) Gonçalves, Felipe Augusto Reis; Aquino, Leonardo Angelo de; Dezordi, Luciel Rauni; Clemente, Junia Maria; Novais, Roberto FerreiraCarrot is one of the most consumed vegetables in Brazil, where the cultivars currently grown present a high yield potential and nutritional demand, which require constant adjustments in fertilization programs for the crop. This study aimed at determining reference values and diagnostic indices by using the DRIS method in three phenological stages of the carrot crop (around 40 and 70 days after sowing and at harvest), as well as evaluating the possibility of early diagnosis for nutritional limitations. For determining the DRIS norms, a database was obtained from leaf samplings, root yields and leaf contents of N, P, K, Ca, Mg, S, B, Cu, Mn and Zn, in carrot commercial fields. The nutritional limitation order was generated as a function of the fertilization response and optimum range of leaf contents. The reference values for K, Ca, Mg, S and Mn were similar in all sampling times. N, P, B, Cu and Zn varied with the stages sampled, indicating the need to standardize the sampling times for these nutrients. Mn, K and Mg were the most limiting nutrients for the crop growth, while Zn and B were the least limiting. There was a correlation between the diagnoses performed at early stages and those performed at harvest for K, Ca, Mg, S and Mn, indicating the possibility of early diagnosis for the deficiency of these nutrients.Item Effect of N and K doses in nutritive solution on growth, production and coffee bean size(Revista Ceres, 2013-02-08) Clemente, Junia Maria; Martinez, Herminia Emilia Prieto; Alves, Leonardo Corrêa; Lara, Marcelo César RosaAn adequate supply of nutrients is essential for obtaining high yields of coffee. The objective of this study was to evaluate the effect of N, K and the N:K ratio on vegetative and reproductive growth of coffee. For this purpose, coffee plants were grown in nutrient solution containing K in the concentrations of 1.08; 2.15; 3.23 and 5.38 mmol L-1 combined with a dose of 6 mmol L-1 N, resulting in the N:K ratios (w/w): 1:0.5; 1:1; 1:1.5 and 1:2.5. The control treatment consisted of the doses 3 and 1.61 mmol L-1 of N and K respectively, resulting in the N:K ratio (w/w) 1.0:1.5. The following variables were evaluated: height, stem diameter, number of nodes of the eighth plagiotrofic branch (index branch), pairs of plagiotrofic branches and number of nodes in the orthotropic branch every three weeks from the beginning of the experiment. Additionally, it was evaluated the chemical composition of processed beans and leaves between the flowering and the rapid expansion stage of the cherry beans, production of cherry beans per plant and classification of beans according to the size. N influenced mainly the characteristics of vegetative growth and K influenced mainly the reproductive growth evaluated by the production. The lowest production resulted in the highest percentages of beans retained on sieves with holes larger than 16/64", while the highest production promoted an increase in the percentage of beans retained on sieves with holes smaller than 16/64".Item Effects of nitrogen and potassium on the chemical composition of coffee beans and on beverage quality(Acta Scientiarum. Agronomy, 2013-04-10) Clemente, Junia Maria; Martinez, Herminia Emilia Prieto; Alves, Leonardo Corrêa; Finger, Fernando Luíz; Cecon, Paulo RobertoThe ratio of nitrogen (N) to potassium (K) is important in the production of specialty coffees because the relative amounts of N and K can either suppress the formation or increase the concentration of compounds that are essential to the flavor and aroma of specialty coffees. The purpose of this study was to evaluate the effect of different N:K ratios (w/w) and K doses on the cup quality of coffee. The concentrations of chemical compounds essentials to achieve good flavor and aroma, the N and K contents, and the caffeine contents of coffee leaves and beans were evaluated in this study. The N:K ratio and the K dose were found to be important factors in cup quality, the best quality corresponding to an N:K ratio of 1:1.56. The best cup quality was obtained from beans with greater PPO activity, caffeine, color index, and sugars and lower total tritatable acidity, pH, electrical conductivity and leached potassium.Item Nutrição nitrogenada e potássica afetando crescimento, produção, composição química e qualidade da bebida de Coffea arabica L.(Universidade Federal de Viçosa, 2010-02-24) Clemente, Junia Maria; Finger, Fernando Luiz; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783681Y0; Cecon, Paulo Roberto; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788114T5; Martinez, Hermínia Emília Prieto; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788276P4; http://lattes.cnpq.br/8345230562555588; Neves, Yonara Poltronieri; http://lattes.cnpq.br/6151512891086957; Santos, Ricardo Henrique Silva; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4723069A2; Sakiyama, Ney Sussumu; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781483H8O nitrogênio e potássio são os nutrientes de maior exigência pelo cafeeiro, sua deficiência pode causar distúrbios metabólicos e afetar o desenvolvimento das plantas de café e consequentemente a produção e características físicas e químicas dos grãos, uma vez que são nutrientes minerais envolvidos na biossíntese e metabolismo de compostos relacionados à qualidade química dos grãos crus do café. Este trabalho objetivou avaliar o efeito do nitrogênio (N), potássio (K) e da relação N:K no crescimento vegetativo, produção e características físicas dos grãos beneficiados de café, bem como o efeito sobre os principais atributos químicos relacionados à qualidade da bebida dos grãos crus do café. Os tratamentos consistiram de quatro relações N:K na solução nutritiva, obtidas mantendo-se constante a concentração de N e variando a concentração de K, mais um tratamento controle com menor concentração de N. Empregaram-se as concentrações 1,08, 2,15, 3,23 e 5,38 mmol/L de K combinados com a dose de 6 mmol/L de N, obtendo-se as relações N:K(p/p):1,0:0,5; 1,0:1,0; 1,0:1,5; 1,0:2,5. Empregou-se um tratamento controle com as doses de 3 e 1,61 mmol/L de N e K, respectivamente resultando a relação N:K(p/p) de 1,0:1,5. Empregaram-se mudas de café da variedade Catuaí Vermelho IAC 99 germinadas em substrato convencional e com um par de folhas definitivas, as quais foram transferidas para o sistema hidropônico de cultivo por sub-irrigação tendo como substrato a argila expandida. Para o referido estudo foram realizadas análises dos seguintes atributos químicos relacionados à qualidade da bebida: atividade da polifenoloxidase, cafeína, fenóis totais, açúcares totais, redutores e não redutores, acidez total titulável, índice de coloração, lixiviação de potássio, condutividade elétrica e pH. Além disso, foram realizadas análises das seguintes variáveis do crescimento vegetativo: altura, número de nós do ramo ortotrópico, número de nós do oitavo ramo plagiotrópico contado a partir da base (Ramo índice), diâmetro do caule, número de frutos do ramo índice, a cada duas semanas após a queda das flores, análise química de folhas e grãos, clorofila total, produção por planta e classificação dos grãos quanto ao tamanho. A relação N:K influenciou a qualidade da bebida avaliada pela prova de xícara. O potássio influenciou todas as variáveis analisadas exceto a atividade da polifenoloxidase. O alto N não influenciou a produção de café cereja e restringiu a qualidade da bebida. A qualidade da bebida foi proporcional a atividade da polifenoloxidase, cafeína, índice de coloração e açúcares redutores e inversamente proporcional a acidez total titulável, lixiviação de potássio, pH e condutividade elétrica. O efeito da relação N:K foi observado nas seguintes variáveis de crescimento vegetativo: altura, número de nós dos ramos plagiotrópicos e diâmetro do caule , no entanto, não foi importante na definição da produção de café cereja e na classificação dos grãos beneficiados quanto ao tamanho. O teor de N nos tecidos das plantas foi proporcional ao N da solução nutritiva, contudo, não foi acompanhado de maiores médias das variáveis analisadas. O K influenciou o crescimento vegetativo até um ponto de máximo obtido com 5,38 mmol/L de K na solução nutritiva, o qual resultou em teores de 3,25 dag/kg de K nas folhas índice do cafeeiro.Item 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 RobertoThe 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.