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AVALIA O DO MéTODO CENTRóIDE PARA ESTUDO DE ADAPTABILIDADE AO AMBIENTE DE CLONES DE Eucalyptus grandis
Rodrigo Barros Rocha,Júpiter Israel Muro-Abad,Elza Fernandes Araújo,Cosme Dami?o Cruz
Ciência Florestal , 2005,
Abstract: A acentuada intera o genótipo x ambiente presente em muitas culturas faz com que estudos de adaptabilidade a ambientes específicos sejam parte integrante dos programas de melhoramento vegetal. A resposta diferenciada dos genótipos a ambientes favoráveis e desfavoráveis pode ser estudada utilizando metodologias baseadas em três estratégias principais: análise de variancia, regress o linear e em estatísticas n o-paramétricas. Este trabalho apresenta uma nova metodologia para estudo de intera o genótipo x ambiente que se baseia na compara o de valores de distancia cartesiana entre os genótipos e quatro referências ideais em uma dispers o de componentes principais, visando a facilitar a recomenda o de genótipos. Esse método, chamado de método centróide, difere em rela o aos métodos baseados em análise de variancia por permitir o direcionamento dos cultivares em rela o à varia o ambiental e pela facilidade de identifica o dos genótipos, dispensando a análise simultanea de vários parametros como nos métodos baseados em regress o. Para exemplificar sua aplica o, foram avaliados 25 genótipos provenientes de testes clonais de Eucalyptus grandis aos 74 meses de idade plantados em quatro ambientes em modelo fatorial e delineamento em blocos ao acaso com seis repeti es, sendo que os efeitos de genótipos foram considerados fixos e os efeitos de blocos e ambientes aleatórios. Foram identificados quatro clones de boa adaptabilidade geral além de outros de adapta o específica a grupo de ambientes que também podem ser recomendados visando a capitalizar o efeito da intera o. Os resultados foram comparados com os obtidos pela metodologia de regress o proposta por Eberhart e Russel (1966) e pelo método proposto por Lin e Binns (1988) e permitem concluir que o método centróide foi eficiente na identifica o dos clones de Eucalyptus grandis avaliados de comportamento diferenciado entre os ambientes; associado à facilidade de recomenda o e ordenamento dos genótipos a grupos de adaptabilidade específicos.
Qualidade da Secagem de Eucalyptus grandis Mediante Vaporiza??o Simultanea em Toros e em Madeira Serrada
Calonego,Fred W.; Severo,Elias T. D.; Coneglian,Ademilson; Barreiros,Ricardo M.;
Silva Lusitana , 2006,
Abstract: in the present study, the union of the board pre-steaming and logs steaming techniques on eucalyptus grandis wood drying quality, was evaluated. in order to do so, logs with diameters from 20 to <25, 25 to <30 and 30 to <35 cm, from the horto florestal, mandurí, s?o paulo, brazil, were used. half of the logs were steamed during 20 hours at 90oc of temperature. later the logs (control and steamed) were sawed with tangential system and the boards were pre-steamed during 3 hours at 90oc of temperature after 1 hour of initial heating. the boards were dried in the dry-kiln pilot and the drying defects were evaluated. the results shown that the union of the board pre-steaming and logs steaming techniques caused: (1) reduction of the number of boards with drying defects classified as severe in the three logs diameters classes; (2) significant reduction of the average drying defects rate in the boards removed from the three logs diameter classes.
Eficiência de utiliza??o de nutrientes e sustentabilidade da produ??o em procedências de Eucalyptus grandis e Eucalyptus saligna em sítios florestais do estado de S?o Paulo
Santana, Reynaldo Campos;Barros, Nairam Félix de;Neves, Júlio Cézar Lima;
Revista árvore , 2002, DOI: 10.1590/S0100-67622002000400007
Abstract: nutrient use efficiency and growth of three provenances of eucalyptus grandis and three of e. saligna were evaluated, at 78 months of age, on various sites located in the counties of angatuba, itapetininga, paraibuna, s?o miguel arcanjo and s?o josé dos campos, in the state of s?o paulo, brazil. there was a variation in biomass production among sites, with the highest yield being obtained in s?o miguel arcanjo, followed by paraibuna. the other counties constituted a third group. the genetic materials revealed variations in nutrient use efficiency from site to site. e. grandis showed greater n, p, and mg nutrient use efficiency than e. saligna. there were no appreciable differences in efficiency between the two species for ca and k. high nutrient use efficiency is not necessarily related to high productivity. ca and k are the nutrients that could most limit productivity of the next rotation, when harvesting the stem. however, this limitation can be substantially reduced, especially for ca, if only stemwood is harvested.
Eficiência de utiliza o de nutrientes e sustentabilidade da produ o em procedências de Eucalyptus grandis e Eucalyptus saligna em sítios florestais do estado de S o Paulo  [cached]
Santana Reynaldo Campos,Barros Nairam Félix de,Neves Júlio Cézar Lima
Revista árvore , 2002,
Abstract: A eficiência de utiliza o de nutrientes (EUN) e o crescimento de três procedências de Eucalyptus grandis e de três de E. saligna foram avaliados, aos 78 meses de idade, nos municípios de Angatuba, Itapetininga, Paraibuna, S o Miguel Aracanjo e S o José dos Campos, Estado de S o Paulo. Houve varia o na produ o de biomassa entre os municípios, sendo as maiores produtividades observadas em S o Miguel Aracanjo, seguido por Paraibuna, com os demais municípios constituindo um terceiro grupo. Dentro dos municípios n o houve diferen a entre materiais genéticos na produ o de biomassa, exceto em S o Miguel Arcanjo. Os materiais genéticos mostraram varia es na EUN entre locais. Observou-se maior EUN de E. grandis em rela o ao E. saligna para N, P e Mg, n o havendo diferen as apreciáveis de eficiência entre as duas espécies para Ca e K. A alta EUN n o está necessariamente ligada à alta produtividade. O Ca e o K s o os nutrientes que mais poder o limitar a produtividade do próximo ciclo, quando se considera a colheita do tronco. Entretanto, esta limita o pode ser substancialmente reduzida, principalmente para o Ca, se a colheita for realizada apenas do lenho.
Estimativa do tempo de vaporiza??o de toras de Eucalyptus grandis
Calonego, Fred Willians;Severo, Elias Taylor Durgante;
Revista árvore , 2006, DOI: 10.1590/S0100-67622006000300016
Abstract: the aim this study was to adjust the general model for determining log steaming time, proposed by steinhagen et al. (1980), for eucalyptus grandis wood. in order to do so, logs with diameter from 20 to <25, 25 to <30 and 30 to <35 cm were collected from 14 trees of eucalyptus grandis derived from the `horto florestal' nursery, manduri, s?o paulo. a thermocouple was inserted into each log near its center. the logs were steamed during 20 hours at 90oc and 100% relative humidity. a data logger recorded the temperatures during the thermal treatment. it was concluded that the steinhagen et al. (1980) model cannot be directly used for this species in study and corrections factors are proposed for the utilization of the general model for log steaming time, developed by steinhagen et al. (1980), for eucalyptus grandis wood.
Weed control strip influences the initial growth of Eucalyptus grandis
Silva, Jo?o Renato Vaz da;Alves, Pedro Luís da Costa Aguiar;Toledo, Roberto Estev?o Bragion de;
Acta Scientiarum. Agronomy , 2012, DOI: 10.4025/actasciagron.v34i1.12252
Abstract: reforestation in brazil is conventionally carried out with a 50-cm weed control strip, using mechanical or manual hoeing or herbicides. the aim of this study was to determine effects of varying the width of the herbicide-treated strip on the establishment of eucalyptus grandis. eucalyptus plants were transplanted in araraquara and altinópolis counties, s?o paulo state, brazil. in araraquara, the following treatments were evaluated: 0, 25, 50, 75, 100 and 150-cm wide strips, treated with herbicide, on either side of the eucalyptus row; in altinópolis, the width of the strip on either side of the eucalyptus row was 0, 25, 50, 75, 100, 125 or 150 cm. were evaluated dry matter of leaves, branches and stem and leaf area at 270 days after planting (270 dap), chlorophyll content (400 dap), stem diameter and eucalyptus plants height (410 dap). in araraquara, the main weed was panicum maximum, and in altinópolis, it was rhynchelytrum repens. for both areas, a minimum of 75 cm of treated strip was required to minimise weed interference with eucalyptus plants’ development.
Combining ability of elite clones of Eucalyptus grandis and Eucalyptus urophylla with Eucalyptus globulus
Bison, Odair;Ramalho, Magno Antonio Patto;Rezende, Gabriel Dehon Sampaio Pe?anha;Aguiar, Aurélio Mendes;Resende, Marcos Deon Vilela de;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000300019
Abstract: in brazil, eucalyptus breeding programs for cellulose production has used two species, eucalyptus grandis and eucalyptus urophylla. nevertheless, it would be useful to introgress alleles from other species to improve wood quality and volume. the objective of this research was to evaluate the hybrid potential of elite clones of e. grandis and e. urophylla from the aracruz celulose company s. a. with eucalyptus globulus clones. to do so, six elite clones were crossed with ten e. globulus clones in a half-diallel mating design. the resulting hybrid combinations as well as the four check clones were evaluated in randomized complete block experiments with single plant plots and 40 replicates from september to october 2001 at three brazilian sites, aracruz and s?o mateus in the espírito santo state and caravelas in bahia state. two years later the circumference at breast height (cbh) and the wood density (wd) were measured. the means were submitted to diallel analysis according to the griffing method (1956), adapted by geraldi and miranda filho (1988). although the number of clones involved was small, the crossings of elite clones of e. grandis and e. urophylla with clones of e. globulus were promising, especially for wood quality gains.
Soil attributes and wood quality for pulp production in plantations of Eucalyptus grandis clone
Gava, José Luiz;Gon?alves, José Leonardo de Moraes;
Scientia Agricola , 2008, DOI: 10.1590/S0103-90162008000300011
Abstract: the soil attributes can affect the wood quality of eucalypt, which may result in considerable effect on cellulose production. this study evaluated the effect of different physical and chemical soil attributes on wood quality of eucalyptus grandis for cellulose production. five sites were selected at the western plateau of the state of s?o paulo, planted with one clone of eucalyptus grandis, with ages ranging between 6.5 and 7.0 years. four soil types, with texture ranging from sandy to very clayey were found. at each site, three experimental plots were allocated with 100 trees each. trees representative of each class frequency of diameter at breast height were harvested. their biomass and wood components were characterized. the wood productivity and quality was affected by physical attributes of soil, mainly clay content, which is directly related to the amount of available water. basic wood density did not changed at different soil types. total lignin content decreased and holocellulose content exponentially increased as soil clay content increased (until about 350 to 400 g kg-1 of clay). the wood extractives content was not affected by soil attributes. screened cellulose yield exponentially increased with soil clay content.
Seed viability constants for Eucalyptus grandis
Fantinatti, Jussara Bertho;Usberti, Roberto;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007000100015
Abstract: this work aimed to analyse eucalyptus grandis w.hill ex maiden seed behaviour, under controlled deterioration, and to estimate viability equation constants for the species. seeds were harvested in the growing season of 1999, and the moisture contents were adjusted from 11.3% to a range between 1.2 and 18.1% at 25oc. the subsamples were sealed into laminate aluminium-foil packets, for storage in incubators at 40, 50 and 65±0.5oc. the seeds presented orthodox performance, in which the constants for predicting seed longevity of e. grandis were ke = 9.661, cw = 6.467, ch = 0.03498 and cq = 0.0002330. the usual and inverse relationship between water content and seed longevity was also observed. the lowest moisture content limit for application of the viability equation at 65oc was 4.9%, estimated under hygroscopic equilibrium with 23% of relative humidity in the storage environment.
SPATIAL DEPENDENCE STUDY OF Eucalyptus grandis DENDROMETRIC CHARACTERISTICS
José Marcio de Mello,Jo?o Luís Ferreira Batista,Marcelo Silva de Oliveira,Paulo Justiniano Ribeiro Júnior
CERNE , 2005,
Abstract: The knowledge of spatial continuity structure of dendrometric characteristics is crucial in forest inventory, managementand planning. The inclusion of spatial continuity effect in inventory analysis provides stable and safe results that can be used in forestmanagement and planning. This paper evaluated the structure of spatial continuity of four dendrometric characteristics obtainedby two sampling procedures. Data were collected in 987 hectares of Eucalyptus grandis, located in the south of S o Paulo State.Two sampling procedures were used, systematic grading and unencumbered systematic. For each plot from the two samples, thefollowing dendrometric characteristics were measured: volume, quadratic average diameter, basal area and average height of thedominant trees. For each one of these characteristics, anisotropic and isotropic semi variogrammes were built, in order toevaluate the spatial continuity structure. The semi variogrammes were built using the moment estimator method. The mainauthorized functions were adjusted to the experimental semi variogrammes, by The Minimum Square Method. The behavior of thespatial continuity was evaluated through the degree of spatial dependence and of the assigned semi variogrammes for the fourcharacteristics, in the appraised sampling methods, respectively. All appraised characteristics presented spatially structured,independently of the appraised sampling procedure. The continuity structure of the four characteristics was isotropic, i.e., thevariance among pairs of points depends on the separation vector h. Therefore, unidirectional semi variogrammes can be built forall appraised characteristics. The results suggest that, in forest inventory, the spatial component should be considered, i.e., plotsshould not be treated separately.
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