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ABSTRACT Species within the genus Corymbia are regarded as potential alternatives to Eucalyptus. In addition to having superior wood quality, Corymbia spp. are tolerant to most pests, diseases, and abiotic stresses that affecting Eucalyptus plantations, including physiological disorders, water deficit, and wind damage. However, environmental stresses stimulate kino production, which decreases the quality of pulp and sawn wood. This study aimed to develop a method for evaluating kinoand estimate genetic parameters in Corymbia. For this, 16 Corymbia (C. citriodora × C. torelliana) hybrid clones and 5 clones of Eucalyptus were used. Two evaluation methods (M1 and M2) were tested for kino evaluation; M1 consisted of drilling the bark with Pilodyn and M2 consisted of drilling the heartwood with Pilodyn. The following kino parameters were evaluated: exudation incidence, exudate length which flowed over the stem, and exudate weight. Genetic parameters were estimated by a mixed model method (REML/BLUP). The significance of random effects of the statistical model was tested by the likelihood ratio test. Significant clone effects were obtained for all kino parameters, except for exudate length as assessed by M2. Kino parameters determined by M1 exhibited higher heritability and accuracy. Therefore, M1 should be preferred for kino evaluation in Corymbia.

As in other countries, In Brazil, new genetic materials of Eucalyptus spp. and their hybrids are multiplied through cloning. These materials, currently in experimental trials, must undergo several stages to select the best ones for pulp and paper production. Therefore, new studies on wood quality are essential. Therefore, this study aimed to group 11 clones of Eucalyptus spp. wood, from a clonal plantation in the municipality of Palmital, São Paulo State, for the production of paper and cellulose. For this purpose, four trees of each clone of 4-year-old Eucalyptus spp. were collected. From each tree, a log of 1 m in length was taken from the base of the tree, for the study of the characterization of the basic density and cellular dimensions of the wood. The results showed that there were significant differences between clones for basic density, fiber length, vessel element length and fiber wall thickness. The Runkel ratio, wall fraction and stiffness coefficient did not show significant differences between the different genotypes. From the results obtained, we can conclude that clones can be differentiated only by basic density, fiber length, vessel element length and fiber wall thickness. The Runkel index, flexibility coefficient and wall fraction of Eucalyptus spp. were more efficient to group the clones into two groups.

Forestry measurement is aimed at volumetric production of wood; however, for the pulp processing industry, the main interest is productivity in wood biomass and, to know this variable, it is necessary to determine the basic wood density (BWD) beforehand. Artificial neural networks (ANN) have been used in the forestry sector quite successfully to describe the dynamics of forest characteristics, such as estimating wood volume. In this context, the objective of this study was to assess the accuracy of the basic wood density estimates by means of ANN’s with Continuous Forest Inventory (CFI) and edaphoclimatic input variables. The database consisted of 3,797 data, from permanent plots of the CFI conducted in Eucalyptus sp stands and edaphoclimatic data from the planting sites. The five best ANNs were selected and the analysis of the estimates was carried out through the correlation between the estimated and BWD, the relative root mean square error (RMSE%) and graphical information. It was observed that both the CFI, edaphoclimatic information and the combination of both are potential and present similar results for the basic wood density estimate, and the errors associated with the estimates are between 3.9% to 3.5%. The ANNs based only on the CFI information presented higher RMSE. The use of ANN’s is feasible for estimating BWD and allows for excellent accuracy statistics.

This article investigates the relationships between soil characteristics (physical and chemical) and wood properties of Persian oak in three different elevation sites. For this purpose, 27 trees were randomly chosen and cut in Zagros forests in western Iran. The test samples were prepared at the stem (breast height) to examine physical and biometrical properties. For each elevation site, four soil samples were obtained at a 0-20 cm soil depth under the canopy of each tree to measure soil properties, including clay, silt soil, sand soil, electrical conductivity, pH, nitrogen, phosphorus, potassium, and organic matter content. Then, the relationship of soil and wood properties was determined by principal component analysis. Results specified that there are a positive correlation between wood density and volumetric swelling with clay and available potassium. Moreover, the results revealed a positive correlation between fiber length, cell wall thickness, and fiber diameter with electrical conductivity, sand percentage, and total nitrogen content, respectively.

Wood use for structural purposes has increased in the last decade in Spain. However, as a raw material, wood needs to comply with requirements that are not always present. Knowledge about the wood quality from the trees on the stand is essential for providing feedback to forest managers and for taking the required actions to obtain suitable silviculture treatments. Two of the main wood species used in construction in Spain, Pinus nigra and Pinus sylvestris, have been studied in order to determine the amount of juvenile wood, which has been identified as a harmful characteristic for its decrease in quality of the physical-mechanical properties of these species. Being relevant for the best quality of timber in the part along the bole where the logs are obtained, the distribution of juvenile wood at different heights and the effect of several silvicultural treatments have had on juvenile wood formation has been considered. The juvenile-mature wood boundary (transition year) was calculated through segmented linear mixed models employing as variables annual latewood density, obtained through micro X-ray densitometry, silvicultural practices, and a drought index. The results show how juvenile and mature wood is distributed along the bole and the proportion of juvenile wood. Its reduction according to the different thinning and pruning silvicultural practices is presented.

The anatomical structure and physical properties of wood change signifcantly among trees of the same species and even among different parts of the same tree. However, studies that characterize radial variation of anatomical characteristics and wood density among clones are scarce, specifcally for the rubber tree [Hevea brasiliensis (Will. ex Adr. De Juss.) Muell]. Thus, the objective of the research was evaluating the anatomical radial variation and density in wood of Hevea brasiliensis clones. For this study, 30 trees, three of each progeny from 10 clones were used. For most clones, we noticed an increase in fber length and vessel diameter towards the bark. For vessel frequency, ray height, width and frequency, we observed a decrease towards the bark. Fiber wall thickness was the most distinctive anatomical characteristic, compared to the others, presenting a trend of thicker walls in the middle position, consequently infuencing basic density clones.

In forest plantations, the productive potential of a given site results from the interaction between genetic materials and environmental conditions. Both are fundamental factors for wood quality and Mean Annual Increment. Knowing the performance of different Eucalyptus urophylla commercial clones under different soil conditions is important for forest planning. Our objective is to evaluate the infuence of soil types on Wood Basic Density and Mean Annual Increment - MAI in two E. urophylla clones. We analyzed the Wood Basic Density of 3- to 8-year-old trees and MAI from two clones grown in four soil types in 14 localities of São Paulo state. ANOVA and Tukey test at 5% probability were performed to test the effect of soil type on Wood Basic Density and MAI. Linear and exponential regression equations were performed between Wood Basic Density x MAI and between MAI x Clay Content, respectively. In general, some soils showed signifcant differences in Wood Basic Density, possibly from climatic variation among sites. Also, the MAI increased exponentially with increase of Soil Clay Content (up to about 25 to 35% of clay), but no correlation was observed between MAI and Wood Density.

ABSTRACT Forest exploitation is conducted in thousands of hectares in Brazil and presents a wide variation in environmental conditions in terms of soil, climate and even management, so identifying clones that may be recommended for these various conditions is a major challenge. In this recommendation, one important character is the mean annual increment in cellulose (MAICEL). This study aimed to evaluate the interaction of different clones and environments for MAICEL in order to verify whether the origin of clone selection affects their performance in other regions and to identify clones based on adaptability. MAICEL data were used for the evaluation of clones from Suzano S.A. in five environments distributed in the states of Espírito Santo, São Paulo, and Mato Grosso do Sul. Clonal tests were arranged in a randomized block design with plots of one plant. Data on MAICEL of the trees at five years were submitted to analysis of variance per environment and, subsequently, to the joint analysis. The clones x environments interaction was expressive for MAICEL, however, the origin of selection does not affect the performance of clones when grown in other regions. Some clones stood out for their adaptability, allowing more security to the company on the recommendation for different environments.

ABSTRACT The objective of this study was to determine the effects of tree age and of pith-bark and base-top positions on anatomical characteristics, and the effect of age on the chemical components of Schizolobium amazonicum (Paricá wood). The material was obtained from commercial plantations in the states of Maranhão and Pará with ages of 5, 7, 9 and 11 years. The first three logs (2.7 m length each) were obtained from the trees of each age. Only the effect of age was analyzed for the chemical characterization of the wood. The dimensions of the fibers increased along the pith-bark direction, while wall thickness decreased and the length of the fibers increased with aging. The width of the fibers and the lume diameter increased in the base-top direction. Paricá wood presented low extractive and hemicellulose content, and high cellulose content. The anatomical characteristics were more affected by the factors under study than the chemical composition, evidencing that the chemical elements of the wood are more stable with aging in relation to the anatomical characteristics.

We studied the wood of Peltophorum dubium (Spreng.) Taub. (Fabaceae), popularly known in Brazil as canafístula, from two seed provenances with different climates. The trees were planted in a third place and cut when 28 years old. Based on differences in seed origins, we hypothesized that some differences would be observed in wood density and anatomical features between provenances and that the radial variation pattern would also differ. However, we did not observe any differences in basic specific gravity or anatomical features between the provenances, which may partly be explained by the conservative nature of wood compared with the external characteristics more susceptible to environmental stresses. In fact, based on the literature and our previous findings, radial variation in P. dubium was similar to that found in many native species, including, for example, increase in basic specific gravity, length and wall thickness of the fibers, increase in vessel diameter and decrease in vessel frequency toward the bark. Based on our results, it can be concluded that P. dubium has high plant adaptability in different locations and that consistency in the quality of its wood can be maintained between provenances, with concomitant implications for both production and use. Estudamos a madeira de Peltophorum dubium (Spreng.) Taub. (Fabaceae), popularmente conhecida no Brasil como canafístula, a partir de duas procedências de sementes com diferentes climas. As árvores foram plantadas em um terceiro lugar e cortadas aos 28 anos. Com base nas diferentes origens das sementes, hipotetizamos que diferenças seriam observadas na densidade aparente e características anatômicas da madeira entre as procedências e que o padrão de variação radial também diferisse. No entanto, não foram observadas quaisquer diferenças na densidade aparente ou nas características anatômicas entre as procedências, o que pode em parte ser explicado pela natureza conservativa da madeira em comparação com as características externas mais sensíveis a estresses ambientais, como as folhas. Com base na literatura e em nossos resultados anteriores, a variação radial em P. dubium foi semelhante à encontrada em muitas espécies nativas, incluindo, por exemplo, aumento na densidade aparente, comprimento e espessura da parede das fibras, aumento no diâmetro e diminuição na frequência de vasos na direção da casca. Concluímos que P. dubium tem alta adaptabilidade em diferentes locais e que a consistência na qualidade de sua madeira pode ser mantida entre procedências, com implicações concomitantes, tanto para produção quanto para a utilização.

The present study aimed to characterize the radial profile of cedar wood (Cedrela fissilis) by the colorimetric technique. Three different trees of approximately 100 years old were selected in Canguçu, Rio Grande do Sul. From each felled tree, discs were removed at breast height (1,3 m) with a thickness of 20 cm and subsequently samples were segmented in centimeter lengths from pith to bark. The samples were conditioned at equilibrium moisture content of 12%, to carry out the colour evaluation with a portable colorimeter Konica Minolta brand in accordance with the CIEL*a*b* method. To determine the segregation of juvenile and mature woods position was employed the apparent specific gravity to 12% (ρa12%) as a parameter. With colorimetric analysis, it was found that the lightness, the green-red coordinate and hue angle presented intimate relation with the transition from juvenile and adult logs. Has a result of blueyellow coordinate and chromaticity showed approximately a linear trend in pith-bark direction.

Durante o crescimento, as árvores produzem diferentes tipos de tecido lenhoso. O xilema produzido nos primeiros anos até certa idade cambial é denominado lenho juvenil e apresenta propriedades físicas, mecânicas, químicas e anatômicas diferentes do xilema produzido após certa idade cambial, isto é, quando as células do câmbio já amadureceram. Dessa forma, um prévio conhecimento sobre a qualidade da matéria-prima produzida é de fundamental importância para melhor aplicabilidade do material. Com base nesse contexto, este trabalho objetivou, a partir de dados de comprimento de traqueídeos e densidade da madeira, delimitar a idade de transição entre os lenhos juvenil e adulto. Para isso, coletaram-se três árvores de Pinus elliottii var. elliottii Engelm., com 35 anos de idade, provenientes da Estação Experimental de Itapetininga, localizada em São Paulo, Brasil. De cada árvore, retiraram-se discos de aproximadamente 5 cm de espessura, extraídos a 0,05 m do solo, que foram utilizados para determinação radial da densidade pelo método de atenuação da radiação gama e comprimento dos traqueídeos. Os resultados da análise de regressão linear indicaram que o lenho juvenil está limitado aos sete primeiros anos de crescimento da árvore e o lenho adulto é formado após os 20 anos de idade. No lenho adulto há diferenças significativas entre as idades médias obtidas através do comprimento dos traqueídeos e da densidade da madeira.Trees produce different types of woody tissue during growth. The xylem produced in the first years until a certain cambial age is called juvenile wood and has different physical, mechanical, chemical and anatomical characteristics from that produced later, when the cambial cells have matured. Thus, prior knowledge of the quality of the wood is of fundamental importance for choosing the best use of the material. This work aimed at using data from length of the tracheid and wood density to define the age transition from juvenile to mature wood. For this, three Pinus elliottii var.elliottii trees, aged 35 years, were collected at the Itapetininga Experimental Station, located in the state of São Paulo, Brazil. From each tree, disks of about 5 cm thick were obtained 0.05 m above the ground and used to determine the radial density by the gamma ray attenuation method and to measure the length of the tracheids. The results obtained by linear regression analysis showed that juvenile wood is limited to the first seven years of tree growth and the formation of mature wood occurs after twenty years. For the mature wood, there are significant differences among the averages obtained from the tracheid length and wood density.

This study was developed aiming at evaluating the use of constant dynamic elastic obtained by non-destructive testing, as a parameter in the estimation of mechanical properties of Eucalyptus cloeziana obtained by destructive test. With equipment emitting ultrasonicwaves from transducers adapted to dry spots of 45 kHz, we determined the ultrasonic velocity relates to distance and time of transmission of the wave along the length of specimens used in test with nominal dimensions of 2.0 x 2.0 x 30.0 cm in thickness, width and length,respectively. To assess the sensitivity of ultrasound, the samples were tested for evidencedestructively in a universal test for determining the modulus of elasticity and rupture in staticbending. The results showed that the ultrasonic method is a fast and efficient tool for inference of non-destructive wood mechanical properties. However, differences in the adjustment of statistical models showed that the best regression parameters were obtained toestimating the modulus of elasticity, compared with the modulus of rupture.

This work aimed to determinate static bending properties (elasticity and strength) of Carya illinoinensis wood in two moisture conditions through of density. For this, five adult trees were felled in the physiographic regions of the Central Depression and the Upper Slopes of the Northeast regions, both in the state of Rio Grande do Sul. For each tree, were removed logs with 2.5 m of length to realize sawing and, later, specimen production with dimension of 2.5 x 2.5 x 41 cm, high dimension to axial direction. The static bending tests were realized with the wood saturated with water (green wood) and theequilibrium moisture content of 12% (dry wood). The results indicate that the presence of water in the timber substantially reduces the values of elasticity and strength. Furthermore, the use of the density is adequate to estimate elasticity and strength properties of Carya illinoinensis wood, both dry wood at 12% moisture content as to the condition of water saturation.

The aimed this study was evaluate the use of dynamic elastic constant obtained by non-destructive test as a parameter in the estimative of mechanical properties of Peltophorum dubium (Spreng.) Taub. wood obtained by destructive test. For this, ultrasonic equipment (not-destructive method) was utilized with point-contact transducersof 45 kHz. The ultrasonic velocity was determined considering the wave transmission along the length of the samples, which dimensions of 2.5 x 2.5 x 41 cm in thickness, width and length, respectively. Based on the relationship between ultrasonic velocity and densityof the wood was determined the dynamic elastic constant. The ultrasonic method sensibility was evaluated with subsequent static-bending test where modulus of elasticity and rupture determination. The results showed that ultrasonic method it’s fast and moderately efficient tool for inference non-destructive of mechanical properties. However, was verified difference in the adjustment of statistical models generated to estimate the properties, and found the best regression parameters to estimate the modulus of elasticity,compared with the modulus of rupture.

The study of physical and mechanical properties of wood is essential for industrial use both in construction and the manufacture of furniture. Thus, the study aimed to determine the physical and mechanical properties of the Araucaria angustifolia wood in terms of three strata phytosociological. For this, 15 trees were felled, five belonging to the upper stratum, the middle stratum five and five for the lower strata. The trees were deployed for the preparation of specimens used for mechanical testing. In the mechanical characterization of the species assays were performed for impact resistance, static bending, compression axial and perpendicular to the fibers. As for the characterization of physical properties, determined the apparent specific gravity at 12% relative humidity for each extract. The results did not show significant differences in the tests of impact resistance and static bending to the strata phytosociological. As for the apparent specific gravity, compression axial and perpendicular there was a change in the values of propertiesbetween the strata phytosociological, is generally butter in the middle and upper strata. Therefore the physical and mechanical properties tend to present higher values these two strata. The data analysis allowed of Araucaria angustifolia wood has moderate mechanical strength when compared with other species studies.

A qualidade da madeira aparentemente está associada às características dendrométricas, que por sua vez são influenciadas pelas condições de crescimento. Os objetivos deste estudo foram a caracterização dendrométrica e a realização de correlações de Pearson entre alguns parâmetros tecnológicos da madeira do híbrido clonal de Eucalyptus urophylla x Eucalyptus grandis sob três estratos silviculturais. Os dados dendrométricos foram analisados mediante a análise de regressão. Os resultados mostraram que o híbrido apresenta comportamento similar ao das demais madeiras da mesma espécie que cresceram em outras regiões, destacando-se a espessura do alburno no E1 (talhadia simples, 70 meses e com um desbaste), com pouca variação ao longo do fuste. Todas as árvores apresentaram, em geral, baixa conicidade ao longo do fuste e baixo volume de casca entre os estratos. Na correlação de Pearson foram avaliados entre si nove parâmetros dendrométricos, sete físicos e três mecânicos, longitudinalmente em seções de 3 m e na posição medula-casca nas duas primeiras toras. Os coeficientes encontrados demonstram haver fortes correlações entre as propriedades, destacando-se a densidade básica em relação às demais características e o coeficiente de anisotropia, ambas importantes no processo de desdobro e secagem da madeira. Não houve correlações significativas nas contrações lineares e volumétricas ao longo do comprimento do fuste. A variação radial mostrou boas correlações entre todas as propriedades mecânicas avaliadas nas duas primeiras toras. Em contrapartida, as propriedades físicas avaliadas na posição radial não apresentaram correlações significativas.Wood quality is apparently associated with the dendrometric characteristics that are influenced by growth conditions. The aim of this study was the dendrometric characterization and realization of Pearson Correlations among some technological parameters in the clonal hybrid wood Eucalyptus urophylla x Eucalyptus grandis grown in three silvicultural extracts. The dendrometric data were analyzed by regression analysis. The results show that the hybrid presents similar behavior to other eucalypt of the same species grown in other places with sapwood thickness in E1 (coppice with 70 months and one thinning), with little variation along the stem. All evaluated trees presented, in general, a low taper along the stem with very little bark volume among the extracts. The Pearson Correlation studied nine dendrometric parameters, seven physical and three mechanical properties. The parameters were evaluated, longitudinally, in three meter sections along the stem and in the pith-bark position in the first two logs according to the Pearson's Correlation. The coefficients demonstrated a strong correlation among the properties, with basic density being highly correlated to the other characteristics and anisotropic coefficient, important in the process of sawing and drying wood, as well as sapwood thickness. The correlation to the height relationship wasn't significant to the linear and volumetric shrinkage. Radial variation showed a good correlation among all the evaluated mechanical properties in the two first logs. On the other hand, the physical properties in the radial position didn't present significant correlations with tangential shrinkage.

Setenta e cinco amostras de madeiras de clones de Eucalyptus, obtidas de diferentes regiões geográficas do Brasil, foram utilizadas para este estudo. Análises estatísticas demonstraram que a carga de álcali ativo para polpação, o teor de lignina e o teor de extrativos apresentaram efeitos significativos no rendimento da polpação kraft. A densidade básica da madeira não afetou significativamente o rendimento da polpação, mas sim o consumo de madeira para produção de celulose (m³ madeira/t celulose). Densidade básica, teor de lignina e teor de extrativos foram recomendados como critérios de qualidade da madeira a serem determinados para seleção de clones antes da determinação das características de polpação.Seventy five Eucalyptus wood clones obtained from different geographic regions in Brazil were used for this study. Based on statistical analysis it was demonstrated that an active alkali charge and also wood lignin and extractive contents presented a significant effect on pulping yield. Wood specific gravity did not present a significant effect on pulping yield but affected wood consumption for pulp production (m³wood/ ton pulp). Wood specific gravity, lignin content and extractive content were recommended as criteria to establish wood quality prior to pulping characteristics determination.

Vochysia guatemalensis has been planted over large tropical areas to obtain lumber products. However, compared with naturally-grown material variations in wood color have been noted. In the current research, trees from two 8-year-old fast-grown plantations were sampled from different climatic conditions in order to identify the causes of color variation. The study evaluated the heartwood presence, grain pattern, distance from pith, height within the tree, and effect of drying schedules. The wood color was measured by CIEL*a*b* systems.Wood color of Vochysia guatemalensis is a combination of different tonalities of lightness (L*), redness (a*), and yellowness (b*), however, the lightness and yellowness components were the dominant tones. The color of heartwood and sapwood were different before and after drying. A negative relationship was found between a* and L*, and a* and b* in the undried state, but no relationship was found between L* and b*. The L* index is only correlated with heartwood presence in undried wood. In dried wood, only a relationship between a* and L* is maintained, while other color parameters were affected by climate, drying schedule and heartwood presence, the L* parameter being the most affected. The dried wood displays a lighter surface than the wood before drying. The variations in the dried wood suggest that it is useful to establish dried lots of lumber according to the drying schedule, source and presence of sapwood and heartwood.La especie Vochysia guatemalensis ha sido plantada sobre largas áreas en regiones tropicales. Así mismo, han sido observadas grandes variaciones del color de su madera. En la investigación fueron muestreadas plantaciones de 8 años de edad en diferentes condiciones de clima con el fin de establecer las causes de variación de la madera. Fueron evaluadas la presencia de duramen, el patrón de aserrío, la distancia de la medula y el programa de secado. El color fue medido por el sistema CIELab. Fue encontrado que la madera de V. guatemalensis presenta una combinación de tonalidades de claros (L*), rojos (a*) y amarrillos (b*), siendo los colores claros y amarrillos los tonos dominantes. El color del duramen y la albura fueron diferentes antes y después del secado. Una negativa correlación entre a* y L*, y a* y b* fue encontrada, pero ninguna correlación fue observada entre L* y b*. El índice L* fue el único parámetro correlacionado con el duramen en madera verde. En la madera seca, solamente se mantuvo la relación a* y L*, mientras que los parámetros del color fueron afectados por el clima, programa de secado y duramen, siendo L* el más afectado. La madera seca presentó una superficie más clara que la madera antes del secado. Las variaciones en madera seca sugieren la conveniencia de establecer lotes de secado de acuerdo al programa de secado aplicado, procedencia y presencia de albura y duramen.

The present work aimed to characterize and identify QTLs for wood quality and growth traits in E. grandis x E. urophylla hybrids. For this purpose a RAPD linkage map was developed for the hybrids (LOD=3 and r=0.40) containing 52 markers and 12 linkage groups. Traits related to wood quality and growth were evaluated in the QTL analyses. QTL analyses were performed using chi-square tests, single-marker, interval mapping and composite interval mapping analyses. All approaches led to the identification of similar QTLs associated with wood density, cellulose pulp yield and percentage of extractives, which were detected and confirmed by both the interval mapping and composite interval mapping methodologies. Some QTLs regions were confirmed only by the composite interval mapping methodology: percentage of soluble lignin, percentage of insoluble lignin, CBH and total height. Overlapping QTLs regions were detected, and these, can be the result of major genes involved in the regulation and control of the growth traits by epistatic interactions. In order to evaluate the effect of early selection using RAPD molecular data, molecular markers adjacent to QTLs were used genotype selection. The analysis of selection differential values suggests that for all the traits the phenotypic selection at seven years should generate larger genetic gains than early selection assisted by molecular markers and the combination of the strategies should elevate the selection efficiency.O presente trabalho teve como objetivos a caracterização e identificação de QTLs para características de crescimento e de qualidade da madeira em híbridos de eucalipto derivados do cruzamento entre E. grandis e E. urophylla. Para isso foi desenvolvido um mapa de ligação RAPD pouco saturado (LOD = 3 e r = 0,40) contendo 52 marcas e 12 grupos de ligação. Características de qualidade da madeira e características de crescimento foram avaliadas quanto à presença de QTLs. Foram utilizadas metodologias de mapeamento por marca simples, mapeamento por intervalo simples e mapeamento por intervalo composto para posicionamento e caracterização dos efeitos dos QTLs. Todas as análises geraram resultados consistentes que indicaram a existência de QTLs relacionados com a expressão das características densidade, rendimento de polpa e teor de extrativos confirmados pela metodologia de mapeamento por intervalo simples e pelo mapeamento por intervalo composto e, ainda, outras regiões de menor significância confirmadas apenas pela metodologia de mapeamento por intervalo composto (teor de lignina solúvel, teor de lignina insolúvel, DAP e altura total). A sobreposição de QTLs em determinadas regiões dos grupos de ligação pode ser resultado da existência de regiões do genoma mais importantes para o crescimento e desenvolvimento da planta, indicando a existência de blocos gênicos de maior efeito relacionados com a regulação e controle das características estudadas. Visando comparar o efeito da seleção assistida, marcadores moleculares adjacentes aos QTLs detectados foram considerados como critério para a seleção individual. A comparação dos valores dos diferenciais de seleção evidenciou que a seleção fenotípica aos 7 anos resulta em ganhos superiores à seleção precoce e a combinação das duas estratégias deve contribuir para um aumento na eficiência dos métodos de seleção.

Este trabalho objetivou determinar algumas características anatômicas e dimensões de fibras, elementos dos vasos, células do parênquima e dos raios da madeira da Mimosa tenuiflora (Willd.) Poir. Determinaram-se, ainda, a fração parede das fibras e o porcentual das fibras, dos vasos, dos raios e das células parenquimatosas, bem como a densidade, rendimento e propriedades do carvão vegetal. Conclui-se que a madeira de Mimosa tenuiflora possui poros predominantemente solitários, geminados e múltiplos em agrupamento radial; poros distribuídos em porosidade difusa uniforme; parênquima axial paratraqueal vasicêntrico, vasicêntrico confluente, aliforme e aliforme confluente; raios multisseriados, bisseriados e, menos freqüentemente, unisseriados; e fibras de parede espessa e muito curtas. Obteve-se um rendimento de 39,68% em carvão vegetal, com teor de carbono fixo de 71,70%, densidade igual a 0,51g/cm³, carbono fixo de 71,79 e poder calórico de 6.866 cal/g.The objective of this work was to determine anatomical characteristics, and dimensions of fibers, vessels and parenchyma and ray cells of Mimosa tenuiflora (Willd.) Poir wood. Fibers wall fraction, the percentage of fibers, vessels and ray and parenchyma cells, as well as density and charcoal production and properties were determined. The wood of Mimosa teniflora presents predominantly solitary, geminated and multiple porous in radial groups; porous distributed in uniform diffuse porosity; axial parenchyma paratracheal vasicentric, confluent vasicentric, aliform and confluent aliform; multiseriate, biseiat rays and, less frequently, uniseriate ones; very short fibers with thick walls. Charcoal yield was 39.68% with a 0.51g/cm³ density, 71.79% carbon content and 6886cal/g calorific value.

Vochysia guatemalensis has been planted over large tropical areas to obtain lumber products. However, compared with naturally-grown material variations in wood color have been noted. In the current research, trees from two 8-year-old fast-grown plantations were sampled from different climatic conditions in order to identify the causes of color variation. The study evaluated the heartwood presence, grain pattern, distance from pith, height within the tree, and effect of drying schedules. The wood color was measured by CIEL*a*b* systems. Wood color of Vochysia guatemalensis is a combination of different tonalities of lightness (L*), redness (a*), and yellowness (b*), however, the lightness and yellowness components were the dominant tones. The color of heartwood and sapwood were different before and after drying. A negative relationship was found between a* and L*, and a* and b* in the undried state, but no relationship was found between L* and b*. The L* index is only correlated with heartwood presence in undried wood. In dried wood, only a relationship between a* and L* is maintained, while other color parameters were affected by climate, drying schedule and heartwood presence, the L* parameter being the most affected. The dried wood displays a lighter surface than the wood before drying. The variations in the dried wood suggest that it is useful to establish dried lots of lumber according to the drying schedule, source and presence of sapwood and heartwood. La especie Vochysia guatemalensis ha sido plantada sobre largas áreas en regiones tropicales. Así mismo, han sido observadas grandes variaciones del color de su madera. En la investigación fueron muestreadas plantaciones de 8 años de edad en diferentes condiciones de clima con el fin de establecer las causes de variación de la madera. Fueron evaluadas la presencia de duramen, el patrón de aserrío, la distancia de la medula y el programa de secado. El color fue medido por el sistema CIELab. Fue encontrado que la madera de V. guatemalensis presenta una combinación de tonalidades de claros (L*), rojos (a*) y amarrillos (b*), siendo los colores claros y amarrillos los tonos dominantes. El color del duramen y la albura fueron diferentes antes y después del secado. Una negativa correlación entre a* y L*, y a* y b* fue encontrada, pero ninguna correlación fue observada entre L* y b* . El índice L* fue el único parámetro correlacionado con el duramen en madera verde. En la madera seca, solamente se mantuvo la relación a* y L*, mientras que los parámetros del color fueron afectados por el clima, programa de secado y duramen, siendo L* el más afectado. La madera seca presentó una superficie más clara que la madera antes del secado. Las variaciones en madera seca sugieren la conveniencia de establecer lotes de secado de acuerdo al programa de secado aplicado, procedencia y presencia de albura y duramen.

Este trabalho teve como objetivoverificar a influência do desbaste em propriedadesfísicas e mecânicas da madeira numa população deE. grandis, aos 18 anos de idade. De acordo comos resultados, pode-se concluir que as diferentesintensidades de desbaste não influenciaram,significativamente, nas propriedades em estudo,com exceção da densidade básica, para a qualocorreu diferença entre as intensidades 67% e 75%.De maneira geral, verificou-se tendência dediminuírem os valores dessas propriedades físicase mecânicas, com intensidade de desbaste maiores.Quando se avaliou a variação medula-casca paradensidade básica, resistência à compressãoparalela às fibras e massa específica, a posiçãomais próxima da casca apresentou os maioresvalores destas propriedades, enquanto paravariável retração volumétrica não foi observadadiferença significativa entre a posição maispróxima da casca e posição da medula. Observouse,também, que ocorreram altas correlaçõespositivas entre massa específica e densidade básicae resistência à compressão paralela às fibras.The purpose of this work was to verifythe influence of thinning on physical andmechanical properties of the wood within an18-year-old population of E. grandis. According tothe results, it was able to conclude that a differentintensity in thinning did not influence significantlythe properties under study, except for the basicdensity, where a difference between 67% and 75%intensity occurred. In general, it was found out thatthere was a tendency of they reduce the values ofthe physical and mechanical properties under ahigher intensity of thinning. When the pith to barkvariation was assessed, the parallel compression,the specific mass, and the position of the barkshowed the highest values of those propertieswhereas for the shrinkage significant differencewas not observed between the closest position ofthe pith and position of the bark. It was alsoobserved the occurrence of a high positivecorrelation between the specific mass, basicdensity, and the compression parallel to the grain.

Estudou-se uma nova técnica laboratorial de análise de qualidade da madeira de Eucalyptus sp. para produção de polpa celulósica kraft. A técnica consiste em realizar, simultaneamente, quatro cozimentos de cavacos utilizando diferentes cargas de álcali ativo para estabelecer a característica de deslignificação da madeira. Pelo uso de equações de regressão, calcula-se o álcali ativo necessário para obter o número kappa desejado, o rendimento, a viscosidade e álcali consumido para o kappa objetivo. Os estudos estatísticos evidenciaram que uma única batelada de quatro cozimentos é suficiente, não sendo necessário realizar repetições.A new laboratory technique was tested to determine Eucalyptus sp. wood quality for kraft pulp production. This technique consists in performing four cooks simultaneously using different active alkali charges to establish the wood delignification characteristics. Based on regression equation it is possible to determine the alkali charge necessary to obtain a desired kappa number and the yield, viscosity and the alkali consumed for the target kappa. Statistical analysis demonstrated that a set of four cooks without replication is sufficient to determine the wood quality characteristics.

O vergamento de madeira foi utilizado ao longo dos séculos para a produção de objetos grandes, como estruturas de embarcações ou pequenos utensílios. Mesmo com constantes estudos de vergamento, há carência de melhorias de processo e inclusão de madeiras de baixo valor comercial. Assim, o presente trabalho analisou a madeira vergada de Eucalyptus grandis tratada por diferentes tempos de exposição à vaporização e ao cozimento. Foram analisados o número de tipos de defeitos por peça vergada (Nºdef), a variação no teor de umidade perante os tratamentos (∆Tu), a pressão de extremidade (Pe) e a perda de forma circular (Pf). Verificou-se que as variáveis diferem significativamente entre os tipos de tratamento de vaporização e cozimento, exceto para o Nºdef. Os tempos de tratamento não apresentaram efeito significativo. Concluiu-se que a espécie é aceitável para vergamentos em raios inferiores ao utilizado no presente estudo. Adicionalmente, a vaporização mostrou ser o melhor tratamento, por apresentar melhores parâmetros de qualificação.