Anais da Academia Brasileira de Ciências
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13096
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Item Physical characterization of Arabica ground coffee with different roasting degrees(Academia Brasileira de Ciências, 2019) Nakilcio´glu-tas, Emine; Ötles, SemhRoasting is a determinative operation on the final quality of coffee. Roasting process causes physical, chemical and sensory changes on coffee. In this study roasting degree effect on physical properties of Arabica fine ground coffee was examined. The bulk properties, particle property, reconstitution properties, moisture content, water activities and color properties were investigated in different roasting degrees of coffee. The results showed that the physical characteristics of coffee samples were influenced by the degree of roast. To have longer shelf life, lower cost and better physical attributes of Arabica fine ground coffee, the roasting process should be kept at a lower degree. At the same time the requests and expectations of customer should also be considered.Item Genetic diversity of promising ‘conilon’ coffee clones based on morpho-agronomic variables(Academia Brasileira de Ciências, 2018) Giles, João Antonio D.; Partelli, Fábio L.; Ferreira, Adésio; Rodrigues, Joice P.; Oliosi, Gleison; Silva, Fernando H. Lima eKnowledge of the genetic variability of a population is essential to guide its preservation and maintenance in addition to increasing the efficiency of genetic breeding programs. On this basis, this study was conducted to evaluate the genetic diversity of Coffea canephora genotypes using multivariate statistical procedures applied to a set of morpho-agronomic variables. The materials employed in this study constitute a crop located in Vila Valério - ES, Brazil, where the genotypes are arranged in a randomized-blocks experimental design with four replicates. Significant differences were detected by the F test at the 1% or 5% probability levels among the genotypes for all evaluated traits, demonstrating heterogeneity of genetic constitution in the studied population, which is favorable to breeding, as it indicates the possibility to identify superior and divergent individuals. Based on the generalized Mahalanobis distance, the most divergente combinations were obtained between genotypes 23 and 10 (256.43) and 23 and 17 (250.09). The clusters formed by Tocher’s optimization and the UPGMA hierarchical method agreed, both similarly grouping the genotypes into three clusters. Of the analyzed traits, mature fruit weight (19.08%), yield (15.50%), plant diameter (12.42%), and orthotropic-shoot internode length (10.94%) were the most efficient to explain the dissimilarity among the genotypes.Item Scale insects (Hemiptera: Coccoidea) associated with arabica coffee and geographical distribution in the neotropical region(Academia Brasileira de Ciências, 2017) Fornazier, Maurício J.; Martins, David S.; Willink, Maria Cristina G. de; Pirovani, Victor D.; Ferreira, Paulo S. F.; Zanuncio, José C.Coffee is one of the most important Brazilian agricultural commodities exported, and Minas Gerais and Espírito Santo States are the main coffee producers. Scale insects are important coffee pests, and 73 species of Cerococcidae (3), Coccidae (18), Diaspididae (6), Eriococcidae (1), Ortheziidae (3), Pseudococcidae (21), Putoidae (2) and Rhizoecidae (19) have been associated with roots, branches, leaves, flowers and fruits of Arabica coffee in the Neotropics. Eight species were found associated with Arabica coffee in Minas Gerais and Espírito Santo States in this study, and Coccidae was the most frequent family. Coccus alpinus, Cc. celatus, Cc. lizeri, Cc. viridis, and Saissetia coffeae (Coccidae) were found in both states; Alecanochiton marquesi, Pseudaonidia trilobitiformis (Diaspididae), and Dysmicoccus texensis (Pseudococcidae) were only found in Minas Gerais. Alecanochiton marquesi and P. trilobitiformis are first reported in Minas Gerais, and Cc. alpinus in Espírito Santo, on Arabica coffee. All scale insect species were associated with coffee leaves and branches, except D. texensis, associated with coffee roots. Fourty seven scale insect species have been found occurring in Brazilian Arabica coffee, and in Espírito Santo (28) and Minas Gerais (23). Widespread and geographical distribution of each species found are discussed.Item Hormesis with glyphosate depends on coffee growth stage(Academia Brasileira de Ciências, 2013) Carvalho, Leonardo B. de; Alves, Pedro L. C. A.; Duke, Stephen O.Weed management systems in almost all Brazilian coffee plantations allow herbicide spray to drift on crop plants. In order to evaluate if there is any effect of the most commonly used herbicide in coffee production, glyphosate, on coffee plants, a range of glyphosate doses were applied directly on coffee plants at two distinct plant growth stages. Although growth of both young and old plants was reduced at higher glyphosate doses, low doses caused no effects on growth characteristics of young plants and stimulated growth of older plants. Therefore, hormesis with glyphosate is dependent on coffee plant growth stage at the time of herbicide application.Item The 15N isotope to evaluate fertilizer nitrogen absorption efficiency by the coffee plant(Academia Brasileira de Ciências, 2007) Fenilli, Tatiele A. B.; Reichart, Klaus; Bacchi, Osny O. S.; Trivelin, Paulo C. O.; Dourado-Neto, DurvalThe use of the 15N label for agronomic research involving nitrogen (N) cycling and the fate of fertilizer-N is well established, however, in the case of long term experimentation with perennial crops like citrus, coffee and rubber tree, there are still shortcomings mainly due to large plant size, sampling procedures, detection levels and interferences on the system. This report tries to contribute methodologically to the design and development of 15N labeled fertilizer experiments, using as an example a coffee crop fertilized with 15N labeled ammonium sulfate, which was followed for two years. The N of the plant derived from the fertilizer was studied in the different parts of the coffee plant in order to evaluate its distribution within the plant and the agronomic efficiency of the fertilizer application practice. An enrichment of the fertilizer-N of the order of 2% 15N abundance was sufficient to study N absorption rates and to establish fertilizer-N balances after one and two years of coffee cropping. The main source of errors in the estimated values lies in the inherent variability among field replicates and not in the measurements of N contents and 15N enrichments of plant material by mass-spectrometry.