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Longitudinal and radial variation of extractives and total lignin contents in a clone of Eucalyptus grandis W.Hill ex Maiden x Eucalyptus urophylla S. T. Blake  [PDF]
Marina Donária Chaves Arantes,Paulo Fernando Trugilho,José Tarcísio Lima,Angélica de Cássia Oliveira Carneiro
CERNE , 2011,
Abstract: The objective of this work was to determine concentrations of extractives and total lignin along with their radial and longitudinal variations in wood from a clone of Eucalyptus grandis W.Hill ex Maiden x Eucalyptus urophylla S. T. Blake at age six years. Longitudinal samples were taken at 2%, 10%, 30% and 70% of the commercial height of trees, and radial samples were taken from each longitudinal position, the number of samples depending on the diameter of each disk. Results led to the conclusion that, overall, concentrations of extractives and total lignin in the wood tended to decrease with increasing distance from the pith and tended to increase in portions closer to the tree base.
Estimates of genetic gains for growth traits in young plants of Eucalyptus urophylla S. T. Blake  [PDF]
Thais Galhardo Godoy,Sebasti?o Carlos da Silva Rosado
CERNE , 2011,
Abstract: The objective of this study was the selection of superior genotypes for growth traits, correlating them to initial height growth in the field, at age eight months. A random block design was used in the nursery, with eight clones, three replicates and four plants per plot. And a random block design was also used in the field, with eight clones, four replicate blocks and nine plants per plot. Data being analyzed in the nursery at age 120 days included: height of field seedling, at age eight months (Hc), height of nursery seedling (Hm), root collar diameter (Dc), shoot diameter (Db), shoot dry matter (PMSPA), root dry matter (PMSR), total dry matter (PMST), ratio of shoot dry matter to root dry matter (PMSPA/PMSR), Dickson quality index of root collar diameter (IQD-Dc), Dickson quality index of shoot diameter (IQD-Db). Analyses of variance showed that significant genetic differences exist among clones for all traits and, given the high heritability values found, the estimated genetic gains were generically very high. As for predicted indirect genetic gain, selection in nursery seedlings for Dc, PMSPA/PMSR, IQD-Dc provided the highest values of indirect gain in field seedling height.
Estimativa da biomassa e do comprimento de raízes finas em Eucalyptus urophylla S.T. Blake no município de Santa Maria-RS
Witschoreck, Rudi;Schumacher, Mauro Valdir;Caldeira, Marcos Vinicius Winckler;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000200008
Abstract: this study aimed to estimate the amount of biomass and the length of fine roots (< 2mm of diameter) in different soil depths for the 10 -year-old species eucalyptus urophylla s.t. blake. the experiment was conducted santa maria, rs on the campus of the federal university of santa maria. the plots were 27 m long and 14 m wide and 3 m x 2 spaced. four monoliths of 25 cm x 25 cm x 60 cm were sampled and divided into six geometric sections at depths of 0-10, 10-20, 20-30, 30-40, 40-50, 50-60 cm. roots were separated from the soil by using a set of two sieves (2 mm and 1 mm) and water jets. the intersection method was used to determine root length producing photos with the use of a scanner. the results showed a high concentration of fine roots in the first 20 cm of the soil. fine root total biomass found for eucalyptus urophylla was 1.451,6 kg/ha, 57.9% were concentrated in the first 20 cm of soil. the total length of fine roots was 27.968,9 km/ha, with 64.3% being in the first 20 cm of depth.
Teor de Lignina em Plantas de Eucalyptus urophylla S. T. Blake Tratadas com Fitorreguladores
Oliveira,Maria Beatriz de; Abreu,Heber dos Santos; Pereira,Regina Paula Willemen;
Silva Lusitana , 2009,
Abstract: lignin is an indispensable biomacromolecule for various biological processes in plants. one of the most important lignin functions is to maintain the rigidity needed for the verticality of the main stem and to ensure the water and mineral movement. this research was carried out with seedlings of eucalyptus urophylla and the results may facilitate further studies in biotechnology. in this research were applied different concentrations of plant growth regulators jasmonic acid (1 and 2 μm) and 2,4-dichlorophenoxyacetic acid (18.12 and 36.24 μm)]. the experiment was full factorial with a completely randomized design. the results showed that the treatment with jasmonic acid in its first dosage enabled the process of lignin formation and in a second dosage disabled the process of lignification. in the treatment with 2,4-d (a1-18.12 μ m) the process of lignification contributed to reduce the deposition of lignin, while (a2 - 36.24 μm) had a smaller reduction compared with the standard. the combined treatments j1a1 (1 μm jasmonic acid and 18.12 + μ m 2,4-d) and j1a2 (2 μ m jasmonic acid and (36.24 + μ m 2,4-d) showed synergistic effect with a predominance of jasmonic acid on lignin formation. the results pointed out for change in the lignification process as well as protein and anatomical features.
Morphological characterization of calli of Eucalyptus urophylla S. T. Blake subjected to concentrations of boron and calcium  [PDF]
Raquel Trevizam,Gilvano Ebling Brondani,Felipe Uassurê Nery,Antonio Natal Gon?alves
CERNE , 2011,
Abstract: This study aimed to evaluate the effect of B and Ca concentrations on morphological responses and size of calli in Eucalyptus urophylla. Calli were obtained from the mid portion of hypocotyls removed from in vitro germinated seedlings. The callus structures were cultivated for 21 and 31 days, being kept in a modified N7 medium with concentrations of B (0; 25; 50; 100 and 200 μM H3BO3) and Ca (0; 3.75; 7.5; 11.25 and 15 mM CaCl2.2H2O). Size of calli, presence of roots, friability, viscosity, presence of globular structures on the surface and presence of pigments were analyzed. Overall, the shorter culture period (21 days) allowed better development of callus structures. The combination of 50 μM H3BO3 with 7.5 mM CaCl2.2H2O at 21 days, and 100 μM H3BO3 with 1.13 mM CaCl2.2H2O at 31 days, provided best results. Rhizogenesis responded differently according to B and Ca concentrations. Simultaneous omission of B and Ca inhibited the rhizogenesis, causing disruption of the callus, favored formation of globular and friable structures, with presence of anthocyanin. High concentrations of calcium promoted root induction in calli.
Efeito da incorpora??o de casca de café nas propriedades físico-mecanicas de painéis aglomerados de Eucalyptus urophylla S.T. Blake
Mendes, Rafael Farinassi;Mendes, Lourival Marin;Guimar?es Júnior, José Benedito;Mori, Fábio Akira;César, Antonia Amanda da Silva;
Ciência e Agrotecnologia , 2010, DOI: 10.1590/S1413-70542010000300012
Abstract: the objective of this study was to evaluate the influence of the incorporation of coffee husks in the production of particleboard with eucalyptus urophylla s.t. blake. the panels were produced incorporating 25%, 50%, and 75% of coffee husks at three levels of resin phenol-formaldehyde (6, 9 and 12%) and 1% of paraffin. the nominal density of the panels was 0.7 g/cm3 and the cycle of pressing consisted in a pressure of 3.92 mpa under a temperature of 180°c for 8 minutes. by the results it was possible to observe that the physical properties of the particleboard have a linear relationship decreasing with the increase in the level of resin, and increasing with the increase in the percentage of coffee husks, showing higher values of water absorption and thickness swelling. the mechanical properties show a linear relationship growing with the increase of resin level, and decreasing with a reduction the percentage of coffee husk association. the way that the search was conducted, the incorporation of the coffee husks harms the quality of the panels produced.
Estimativa da biomassa e do comprimento de raízes finas em Eucalyptus urophylla S.T. Blake no município de Santa Maria-RS
Witschoreck Rudi,Schumacher Mauro Valdir,Caldeira Marcos Vinicius Winckler
Revista árvore , 2003,
Abstract: O objetivo do presente trabalho foi estimar a biomassa e o comprimento de raízes finas (< 2 mm de diametro), em diferentes profundidades do solo, para a espécieEucalyptus urophylla S.T. Blake, com 10 anos de idade. O estudo foi realizado no município de Santa Maria-RS, no campus da Universidade Federal de Santa Maria. O talh o plantado com eucalipto tem 27 m de comprimento por 14 m de largura, em espa amento 3 x 2 m. Foram amostrados quatro monolitos de 25 x 25 x 60 cm. Os monolitos foram divididos em seis perfis geométricos, nas profundidades de 0-10, 10-20, 20-30, 30-40, 40-50, 50-60 cm. A separa o das raízes do solo foi por meio de um conjunto de duas peneiras (2 e 1 mm de malha) e jatos d'água. Na determina o do comprimento de raízes foi utilizado o método de intersec o, produzindo fotos com o uso de scanner. Os resultados revelaram alta concentra o das raízes finas nos primeiros 20 cm de solo. A biomassa total de raízes finas encontradas para o Eucalyptus urophylla foi de 1.451,6 kg/ha, devendo ser ressaltado que 57,9% estavam concentradas nos primeiros 20 cm de solo. Constatou-se que o comprimento total de raízes finas foi de 27.968,9 km/ha e que 64,3% destes estavam nos primeiros 20 cm de profundidade.
Paulo Ricardo Gherardi Hein,Lo?c Brancheriau Mail
BioResources , 2011,
Abstract: The orientation of cellulose microfibrils in the cell wall along the stem axis has major effects on stiffness and longitudinal shrinkage and is of key importance in wood quality. The aim of this study was to investigate the radial variability of MFA and wood density (ρ) and their relationships in Eucalyptus urophylla wood. Three MFA values were estimated by X-ray diffraction at three points of each one of the 175 tangential sections, and the basic density was measured. A decrease of microfibril angles from pith to bark can be observed in most samples; however, some radial strips presented different patterns of variation. For basic density, a linear significant increase from pith to bark was confirmed. There was no significant correlation between microfibril angle and density. The relationships among the three MFA estimated on tangential sections of wood were strong. The “curvature effect” due to the growth rings had a negligible effect on the three measurements of tangential sections cut near to the pith. This study showed that a single T value measurement by X-ray diffraction, preferably at the centre of the tangential section, is precisely sufficient to estimate the mean MFA of Eucalyptus urophylla wood.
Avalia??o da madeira de Eucalyptus camaldulensis Dehnh e Eucalyptus urophylla S.T. Blake em ensaios de usinagem, visando à produ??o moveleira
Souza, Maria Odete Alves de;Silva, José de Castro;Lucia, Ricardo Marius Della;Evangelista, Wescley Viana;
Revista árvore , 2009, DOI: 10.1590/S0100-67622009000400018
Abstract: the objective of this research was to conduct machining tests in woods of 6 and 8-year-old eucalyptus urophylla and of a ten-year old eucalyptus camaldulensis and to evaluate their possible use by the furniture industry. the wood samples were obtained from six trees of each clone, planted in a consortium with cattle and grain, owned by votorantim metals and zinc. the plantation is located in the neighborhood of the city of vazante, in the state of minas gerais. the following essays were conducted: cut by a table saw either parallel or perpendicular to the grain; shaping; planing; drilling; routing; mortising and drilling for dowels. all the samples yielded satisfactory results, mainly the eight year old eucalyptus urophylla, during parallel-to-the-grain and mortising sawing. woods from the clones tested seem very appropriate for furniture production. in fact, the samples did not show any difficulties during machining.
Renato Lara de Assis,Mozart Martins Ferreira,Alberto Cargnelutti Filho
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v36i3.2036
Abstract: O presente estudo teve por objetivo avaliar o estado nutricional de popula es de eucaliptos (Eucalyptus urophylla), om três anos de idade, plantadas em diferentes densidades, nos eguintes espa amentos: 3,0 m x 2,0 m,0; 3,0 m x 3,0 m; 3,0 m x ,0 m,0; 3,0 m x 5,0 m; 4,0 m x 2,25 m; 6,0 m x 1,5 m; 5,0 m x 1,8 ; e 9,0 m x 1,0 m. O experimento foi conduzido no município de Bocaiúva-MG. Foram avaliados os teores de N, P, K, Ca, Mg, S e B nas folhas, em sete épocas de amostragem. Os teores de nutrientes variaram com a época de amostragem, sendo os menores teores encontrados no período seco, para os nutrientes N, P e K. n o houve intera o entre espa amentos e épocas para os teores de Mg. Os menores teores de Ca ocorreram no mês de dezembro, com exce o da popula o no espa amento 9,0 m x 1,0 m. Os teores de N, P, S e B n o foram influenciados pelos espa amentos, e n o apresentaram níveis considerados como deficientes, independentemente do espa amento e da época. PALAVRAS-CHAVE: Eucalipto; nutri o mineral; densidade. This study aimed to evaluate the mineral nutrition of three years old Eucalyptus urophylla plantations, grown in different population densities in the following spacings: 3.0 m x 2.0 m; 3.0 m x 3.0 m; 3.0 m x 4.0 m; 3.0 m x 5.0 m; 4.0 m x 2.25 m; 6.0 m x 1.5 m; 5.0 m x 1.8 m; and 9.0 m x 1.0 m. The experiment was carried out at Bocaiuva, Minas Gerais State, Brazil. N, P, K, Ca, Mg, S, and B leaf content was evaluated at seven sampling dates. The nutrient content varied with sampling date; N, P, and K lowest levels were found in the dry period. No interaction was observed between spacing and sampling date for Mg. Lowest Ca levels occurred in December, except for 9.0 m x 1.0 m spacing. Spacing did not influence N, P, S, and B content. Independently of spacing and sampling date, N, P, S, and B leaf content did not present levels considered as deficient. KEY-WORDS: Eucalyptus; mineral nutrition; population density; savannah.
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