Pesquisa Agropecuária Brasileira
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/9886
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8 resultados
Resultados da Pesquisa
Item Yield of robusta coffee in different spatial arrangements(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2021-12-10) Espindula, Marcelo Curitiba; Tavella, Leonardo Barreto; Schmidt, Raquel; Rocha, Rodrigo Barros; Dias, Jairo Rafael Machado; Bravin, Maísa Pinto; Partelli, Fábio LuizThe objective of this work was to determine the contribution of the number of stems to the composition of individual plant yield, and to individual and overall robusta coffee (Coffea canephora) yield at different planting densities, using a fixed number of stems per plant. The experiment was carried out in two phases. The first phase was performed from 2011 to 2015, in the municipality of Ouro Preto do Oeste, in the state of Rondônia (RO), Brazil, to evaluate different numbers of stems per plant (1, 2, 3, 4, 5, and 6). The second phase was conducted from 2013 to 2018, in the municipality of Alta Floresta D’Oeste, RO, to evaluate plant densities (at 1,666, 1,904, 2,222, 2,666, and 3,333 plants ha-1), with an initial density of four stems per plant in all treatments. The increase of number of stems per plant promotes a quadratic response to the average and cumulated yield of coffee plants, and the maximum yield is attained with four stems per plant. The number of stems should not exceed four, to avoid their tipping during years of high production. Plant density of 3,333 plants per hectare, with 4 stems per plant and 1 m spacing, promotes the reduction of individual plant yield; however, it results in higher overall crop yield.Item Impacts of water availability on macronutrients in fruit and leaves of conilon coffee(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2018-09) Covre, André Monzoli; Partelli, Fábio Luiz; Bonomo, Robson; Tomaz, Marcelo Antônio; Ramalho, José CochichoThe objective of this work was to evaluate the concentrations and accumulation of macronutrients in conilon coffee (Coffea canephora) fruit, and their concentrations in leaves, over two years, in irrigated and nonirrigated coffee plants. Three-year-old conilon coffee plants of the cultivar Emcapa 8111 genotype 02 were used. An experimental design was carried out in randomized complete blocks, in a split-plot arrangement, with 14 replicates. The main plot factor was irrigation versus nonirrigation of coffee plants, and the split-plot factor was different fruit and leaf collection times. Collections began 10 days after the beginning of flowering and were performed on average every 28 days, until full fruit ripening. At each sampling date, five plants per treatment were picked out, by collecting one plagiotropic branch by plant, separated into fruit and leaves. Each part was dried, weighed, and subjected to the chemical analysis. Macronutrient accumulations and their accumulation rates were determined. According to the regression analysis of the data, fruit macronutrient accumulation curves fit best to sigmoidal equations. Irrigation affects the macronutrient dynamics in fruit and leaves during the fruiting phase of conilon coffee, and increases the accumulation of nutrients in the plant tissues. The macronutrients found in greater quantities are N, K, and Ca, in fruit and leaves, regardless of the irrigation treatment.Item Root system distribution and yield of 'Conilon' coffee propagated by seeds or cuttings(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2014-05) Partelli, Fábio Luiz; Covre, André Monzoli; Oliveira, Marcos Goes; Alexandre, Rodrigo Sobreira; Vitória, Edney Leandro da; Silva, Marcelo Barreto daThe objective of this work was to evaluate the root system distribution and the yield of 'Conilon' coffee (Coffea canephora) propagated by seeds or cuttings. The experiment was carried out with 2x1 m spacing, in an Oxisol with sandy clay loam texture. A randomized complete block design was used, following a 2x9x6 factorial arrangement, with two propagation methods (seeds and cuttings), nine sampling spacings (0.15, 0.30, 0.45, 0.60, 0.75, and 0.90 m between rows, and 0.15, 0.30, and 0.45 between plants within rows), six soil depths (0.10–0.20, 0.20–0.30, 0.30–0.40, 0.40–0.50, and 0.50–0.60 m), and six replicates. Soil cores (27 cm 3 ) with roots were taken from 12 experimental units, 146 months after planting. The surface area of the root system and root diameter, length, and volume were assessed for 13 years and, then, correlated with grain yield. The highest fine root concentration occurred at the superficial soil layers. The variables used to characterize the root system did not differ between propagation methods. Moreover, no differences were observed for net photosynthetic CO 2 assimilation rate, stomatal conductance, internal CO 2 concentrations, and instantaneous water‐use efficiency in the leaves. Cutting‐propagated plants were more productive than seed‐propagated ones.Item Microclimate and development of 'Conilon' coffee intercropped with rubber trees(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2014-11) Partelli, Fábio Luiz; Araújo, André Vasconcellos; Vieira, Henrique Duarte; Dias, Jairo Rafael Machado; Menezes, Luis Fernando Tavares de; Ramalho, José CochichoThe objective of this work was to evaluate the influence of intercropping 'Conilon' coffee (Coffea canephora) with rubber trees on coffee tree microclimate, nutrition, growth, and yield. Rubber trees were planted in two double rows 33 m apart, with 4x2.3 m spacing between plants. Treatments consisted of the distances from the coffee plants to the rubber trees: 3, 6, 9, 12, and 15 m. Measurements of atmospheric variables (temperature, irradiance, and relative humidity), leaf nutrient concentration, internode length of plagiotropic and orthotropic branches, individual leaf area, chlorophyll content, and yield were performed. Intercropping promotes changes in the microclimatic conditions of coffee plants close to rubber trees, with reduction of temperature and irradiance level and increase in air relative humidity. The proximity of the coffee tree to the rubber trees promotes the elongation of the plagiotropic and orthotropic branches and increases the individual leaf area; however, it does not affect leaf concentrations of N, K, Mg, Fe, Zn, and B in 'Conilon' coffee and does not have a negative impact on yield.Item Distribuição do sistema radicular de cafeeiro conilon irrigado e não irrigado(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2015-11) Covre, André Monzoli; Partelli, Fábio Luiz; Gontijo, Ivoney; Zucoloto, MoisesO objetivo deste trabalho foi avaliar a distribuição do sistema radicular do cafeeiro conilon (Coffea canephora) irrigado e não irrigado. Utilizaram-se plantas de conilon da variedade clonal Emcapa 8111, genótipo 02, com cinco anos de idade. Utilizou-se o delineamento inteiramente casualizado, em parcela subsubdividida, com cinco repetições. Os tratamentos consistiram de: presença e ausência de irrigação (parcelas), 13 distâncias do tronco (dez no sentido da entrelinha e três no sentido da linha de plantio) e seis camadas de solo (0–60 cm) nas subparcelas. As raízes foram coletadas, lavadas, digitalizadas e processadas pelo programa Safira, para quantificar área superficial, comprimento, volume e diâmetro. As plantas de conilon não irrigadas apresentaram maiores área superficial, comprimento e volume de raízes por volume de solo, bem como distribuição de raízes menos discrepante na superfície do solo e em profundidade, em comparação às plantas irrigadas. O sistema de irrigação por gotejamento promove maior distribuição de raízes nas plantas irrigadas, na zona compreendida pelo bulbo úmido da irrigação.Item Produção e desenvolvimento radicular de plantas de café 'Conilon' propagadas por sementes e por estacas(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2006-06) Partelli, Fábio Luiz; Vieira, Henrique Duarte; Santiago, Anderson Ribeiro; Barroso, Deborah GuerraO objetivo deste trabalho foi avaliar a produção e o desenvolvimento radicular e da parte aérea de plantas de café 'Conilon', provenientes de sementes e de estacas, no Município de Vila Valério, ES. Foi utilizado o delineamento experimental em blocos ao acaso com dois tratamentos (mudas provenientes de sementes e de estacas) e 12 repetições com cinco plantas úteis por parcela. As avaliações da parte aérea foram realizadas a partir de sete meses do plantio. Foram realizadas seis desbrotas e cinco colheitas. A avaliação do sistema radicular foi realizada aos 52 meses depois do plantio em quatro profundidades (0–10, 10–20, 20–40 e 40–60 cm). Foram quantificados o diâmetro, o comprimento e a área superficial de raízes. As plantas propagadas por estaca emitiram maior número de ramos plagiotrópicos, durante os sete primeiros meses de idade, e menor número de brotos ortotrópicos durante todo o experimento. Não houve diferenças no comprimento e na área superficial de raízes finas, entre plantas propagadas por sementes e por estacas. Houve maior concentração de raízes finas nas camadas superficiais do solo. A produtividade das plantas propagadas por estacas é maior do que a das plantas propagadas por sementes.Item Comparação de dois métodos DRIS para o diagnóstico de deficiências nutricionais do cafeeiro(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2006-02) Partelli, Fábio Luiz; Vieira, Henrique Duarte; Monnerat, Pedro Henrique; Viana, Alexandre PioO objetivo deste trabalho foi comparar as diagnoses nutricionais realizadas pelo DRIS e pelo DRIS modificado (com inclusão da matéria seca), utilizando-se quatro critérios: todas as relações entre nutrientes; as relações com maior razão de variância; as com menor coeficiente de variação e as com valor de relação maior do que um. Foram usados os teores foliares de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn e a produtividade de 56 lavouras orgânicas de café ‘Conilon’, do Estado do Espírito Santo. Verificou-se, para os diferentes métodos e critérios, a freqüência do nutriente cujo índice foi o mais negativo e o mais positivo, a correlação entre o teor do nutriente e seu índice e a correlação entre produtividade e índice de balanço nutricional. O DRIS e o DRIS modificado (DRIS-M) proporcionaram diagnósticos próximos, e os quatro critérios de cálculo de índices DRIS alteraram a ordem de limitação de nutrientes no cafeeiro. O DRIS-M apresenta correlação um pouco mais elevada entre a produtividade e o índice de balanço nutricional, bem como entre o teor do nutriente e o seu índice DRIS.Item Low temperature impact on photosynthetic parameters of coffee genotypes(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2009-11) Partelli, Fábio Luiz; Vieira, Henrique Duarte; Viana, Alexandre Pio; Batista‐Santos, Paula; Rodrigues, Ana Paula; Leitão, António Eduardo; Ramalho, osé CochichoThe objective of this work was to evaluate photoprotective mechanisms related to low positive temperatures in Coffea canephora (Conilon clones 02 and 153) and C. arabica ('Catucaí' IPR 102) genotypes, involved in cold temperature tolerance. To accomplish this, one‐year‐old plants were successively submitted to: temperature decrease of 0.5oC day ‐1 , from 25/20oC to 13/8oC; a three‐day chilling cycle at 13/4oC; and a recovery period of 14 days (25/20oC). During the experiment, leaf gas exchange, chlorophyll a fluorescence and leaf photosynthetic pigment content were evaluated. Total activity of ribulose‐1,5‐bisphosphate carboxylase/ oxygenase (Rubisco) and ribulose‐5‐phosphate kinase (Ru5PK) were quantified to measure the activity of photosynthesis key enzymes. All genotypes showed low temperature sensitivity, but displayed diverse cold impact and recovery capabilities regarding the photosynthetic‐related parameters studied. Catucaí IPR 102 cultivar showed better ability to cope with cold stress than the Conilon clones, especially Conilon 02, and had full recovery of leaf gas exchange, fluorescence parameters, enzymatic activity, and higher contents of the photoprotective pigments zeaxanthin and lutein.