MYCOBIOTA ASSOCIATED WITH Eucalyptus grandis HILL EX MAIDEN LUMBER DURING AIR DRYING

O objetivo principal deste trabalho foi o de acompanhar a secagem ao ar livre da madeira serrada de Eucalyptus grandis conduzida na regi\ue3o de Lavras, MG e identificar a micobiota associada \ue0 madeira em diversas fases da secagem. As t\ue1buas foram cortadas de oito toras de 3,0 m de comprimento, oriundas de tr\ueas \ue1rvores, com 27 anos de idade, plantadas em \ue1rea experimental da UFLA. Dos resultados, p\uf4de-se concluir que a secagem da madeira de Eucalyptus grandis ao ar livre, iniciada em janeiro, consumiu 158 dias at\ue9 atingir umidade pr\uf3xima a 12,5%. A curva de secagem foi representada por uma equa\ue7\ue3o logar\uedtmica com coeficiente de determina\ue7\ue3o (R2) igual a 98,3%. Os fungos causadores de bolores superficiais e de manchas tiveram maior ocorr\ueancia no in\uedcio da secagem. As mais altas freq\ufc\ueancias de fungos, verificadas no in\uedcio da secagem, foram observadas para Penicillium spp. e Pestalotiopsis sp. O fungo Lentinus lepideus ocorreu com maior freq\ufc\ueancia no final da secagem.This work\u2019s main objective was to follow the air-drying of Eucalyptus grandis lumber, carried out in Lavras, MG, and to identify the mycobiota associated with the lumber at various phases of drying. The lumbers were obtained from eight 3.0 meter long logs from 27 year-old trees, planted in an experimental area of UFLA. Results showed that the air-drying of Eucalyptus grandis, started in January, demanded 158 days to achieve moisture content around 12.5 %. The moisture content-time curve was represented by a logarithmic equation with coefficient of determination equal to 98.3 %. The highest occurrence of fungi that cause surface mold and stain was observed at the beginning of the drying. The highest frequencies of fungi were verified at the beginning of the drying for Penicillium spp and Pestalotiopsis sp. The fungus Lentinus lepideus occurred with higher frequency at the end of the drying

Calibration Models And Near Infrared Spectroscopy For Predicting Chemical Properties And Basic Density In Eucalyptus Wood

A espectroscopia no infravermelho pr\uf3ximo (NIRS) surge no campo das ci\ueancias florestais como m\ue9todo n\ue3o destrutivo, r\ue1pido e preciso capaz de predizer propriedades tecnol\uf3gicas da madeira. O objetivo deste trabalho foi aplicar a t\ue9cnica NIRS para desenvolvimento de modelos de calibra\ue7\ue3o para estimar as propriedades qu\uedmicas e a densidade b\ue1sica da madeira de Eucalyptus. Foram utilizados clones de Eucalyptus de tr\ueas anos de idade, provenientes de plantios comerciais nas localidades de Cocais, Guanh\ue3es, Rio Doce-Ipaba e Santa B\ue1rbara, estado de Minas Gerais. As propriedades qu\uedmicas da madeira e a densidade b\ue1sica das \ue1rvores foram determinadas por metodologia tradicional e correlacionadas com as leituras espectrais por meio da regress\ue3o dos m\uednimos quadrados parciais. As calibra\ue7\uf5es para estimar a densidade b\ue1sica da madeira apresentaram coeficientes de correla\ue7\ue3o em valida\ue7\ue3o cruzada (Rcv) variando de 0,56 a 0,97 e rela\ue7\ue3o de desempenho do desvio (RPD) entre 1,1 e 4,7. Os modelos desenvolvidos para estimar o teor de xilanas e glicanas apresentaram Rcv variando de 0,39 a 0,88 e RPD de 1,1 a 2,1. Para o teor de celulose, lignina e extrativos os modelos de calibra\ue7\ue3o apresentaram Rcv entre 0,10 e 0,87 e valores de RPD entre 0,9 e 2,0. A calibra\ue7\ue3o para predi\ue7\ue3o da rela\ue7\ue3o S/G que apresentou o melhor ajuste (Rcv = 0,90 e RPD = 2,3) foi a que representa as \ue1rvores amostradas em Rio Doce. Os modelos de calibra\ue7\ue3o desenvolvidos por meio da espectroscopia no infravermelho pr\uf3ximo mostraram-se eficientes para a densidade b\ue1sica e propriedades qu\uedmicas da madeira de clones de Eucalyptus.Near infrared spectroscopy (NIRS) is a fast, accurate and non-destructive method, capable of predicting wood technology properties. The aim of this study was to apply the NIRS technique for fast prediction of chemical properties and basic density of Eucalyptus wood. Clones of three-year\u2013old Eucalyptus, from commercial plantations in Cocais, Guanh\ue3es, Rio Doce and Santa Barbara localities in the state of Minas Gerais were used. The chemical properties and basic density of the trees were determined using traditional laboratory methods and correlated with the spectral information by Partial Least Squares Regression. The calibrations to estimate basic density showed coefficients of correlation in cross-validation (Rcv) ranging between 0.56 and 0.97 and ratio of performance to deviation (RPD) between 1.1 and 4.7. The carbohydrate, xylan and glucan contents were predicted through models with Rcv ranging from 0.39 to 0.88 and RPD from 1.1 to 2.1. For cellulose, lignin and extractive contents, the models presented Rcv between 0.10 and 0.87 and RPD values between 0.9 and 2.0. The calibration to predict S/G monomer ratio that showed the best adjustment (Rcv=0.90 and RPD=2.3) was in the trees from Rio Doce site. The near infrared spectroscopy proved to be satisfactory to provide the basic density and chemical properties of clones of Eucalyptus wood

ROOT HYDRAULIC CONDUCTIVITY AND PHOTOSYNTHETIC CAPACITY OF EUCALYPT CLONAL CUTTINGS WITH ROOT MALFORMATION INDUCTIONS

A redu\ue7\ue3o do ganho em biomassa de lenho em \ue1rvores tem sido atribu\uedda \ue0 ocorr\ueancia de deforma\ue7\uf5es radiculares ainda na fase de viveiro. O objetivo deste trabalho foi avaliar a condutividade hidr\ue1ulica do sistema radicular, trocas gasosas e a efici\ueancia fotoqu\uedmica de mudas clonais de eucalipto com e sem indu\ue7\ue3o de deforma\ue7\uf5es radiculares. Os tratamentos foram: 1 \u2013 mudas sem a indu\ue7\ue3o de deforma\ue7\uf5es radiculares (produzidas de acordo com metodologia operacional do viveiro da Fibria Celulose S.A.) e 2 \u2013 mudas com indu\ue7\ue3o de deforma\ue7\uf5es radiculares. A indu\ue7\ue3o da deforma\ue7\ue3o radicular n\ue3o resultou em queda no volume radicular. Contudo, deforma\ue7\uf5es radiculares provocaram redu\ue7\ue3o na condutividade hidr\ue1ulica do sistema radicular, assim como foram verificadas quedas na taxa fotossint\ue9tica das mudas ao longo do dia. A queda da taxa fotossint\ue9tica em mudas com indu\ue7\ue3o de deforma\ue7\uf5es radiculares est\ue1 associada a fatores estom\ue1ticos e n\ue3o estom\ue1ticos.The gain reduction of wood biomass in trees has been assigned to root deformations even in the nursery phase. The objective of this work was the evaluation of the root system hydraulic conductivity, gas exchanges and photochemical efficiency of eucalypt clonal cuttings with and without root deformation inductions. The treatments were: 1) operational cuttings without root malformation inductions (grown according to the used methodology of Fibria Cellulose S.A.); 2) root deformation inductions. These inductions did not promote decrease in the root volume. However, the deformations brought reduction of the root system hydraulic conductivity. Lower photosynthetic rates were also observed along the day in the cuttings in the root deformed cuttings. This decreasing rate is connected to stomatal and non stomatal factors

WATER RELATIONS AND ORGANIC SOLUTES IN YOUNG PLANTS OF Jatropha curcas L. UNDER DIFFERENT WATER REGIMES

O objetivo deste trabalho foi avaliar as rela\ue7\uf5es h\ueddricas e os solutos org\ue2nicos em plantas de Jatropha curcas L. submetidas a deficit h\ueddrico e cultivadas em casa de vegeta\ue7\ue3o. O delineamento foi o inteiramente casualizado, com quatro tratamentos h\ueddricos (T1 -100%, T2 - 80%, T3 - 60% e T4 - 40% da Capacidade de Pote) e seis repeti\ue7\uf5es, durante 120 dias. Foi avaliado o potencial h\ueddrico foliar (\u3a8f), teor relativo de \ue1gua, teores de clorofila a, b e total, carotenoides e a estimativa desses pigmentos pelo medidor de clorofila (SPAD). Para a avalia\ue7\ue3o bioqu\uedmica foram quantificados os teores de carboidratos, prote\uednas, amino\ue1cidos e prolina nas folhas aos 60, 90 e 120 dias, e no final do experimento foram avaliados os mesmos solutos nas ra\uedzes. Houve diferen\ue7a significativa entre os tratamentos para \u3a8f nas tr\ueas \ue9pocas de avalia\ue7\ue3o e entre os tratamentos. As plantas com 60% e 40% CP apresentaram valores mais negativos em rela\ue7\ue3o \ue0s plantascontrole ao meio-dia. Aos 120 dias, o tratamento T4 apresentou uma redu\ue7\ue3o de 22,2% no teor relativo de \ue1gua em rela\ue7\ue3o ao controle. Os carotenoides, aos 120 dias, oscilaram entre 0,29 a 0,39 mg/g MF. Os amino\ue1cidos e carboidratos aumentaram nas folhas do tratamento com 80% Capacidade de Pote aos 120 dias de diferencia\ue7\ue3o h\ueddrica. Aos 60, 90 e 120 dias, a clorofila a apresentou um aumento no T4 em rela\ue7\ue3o ao controle. Os teores de clorofila pelo o \ucdndice SPAD variaram de (26,1 a 34,5). Os resultados obtidos sugerem que a Jatropha curcas \ue9 uma esp\ue9cie tolerante \ue0 seca e com grandes potencialidades econ\uf4micas para o semi\ue1rido brasileiro.The objective of this study was to evaluate water and organic solutes in plants of Jatropha curcas L. exposed to water deficit and grown in a greenhouse. The design was completely randomized with four water treatments (-100% T1, T2 - 80%, T3 - T4 and 60% - 40% of pot capacity) and six replicates for 120 days. We evaluated the leaf water potential (\u3a8f), relative water content, content of chlorophyll a, b and total carotenoids and these pigments estimated by chlorophyll meter (SPAD). For biochemical evaluation were quantified levels of carbohydrates, proteins, amino acids and proline in the leaves at 60, 90 and 120 days, and at the end of the experiment, the same solutes in roots. There were significant differences between treatments for \u3a8f the three evaluation periods and between treatments. Plants with 60% and 40% CP showed more negative compared to control plants at noon. After 120 days treatment T4 decreased by 22 2% in relative water content compared to control. The carotenoids at 120 days ranged from 0.29 to 0.39 mg / g MF. Amino acids and carbohydrates in the leaves increased with 80% of treatment capacity pot to 120 days of differentiation water. At 60, 90 and 120 days, chlorophyll a showed an increase in Q4 compared to control. The content of chlorophyll by the SPAD index ranged from (26.1 to 34.5). The results suggest that Jatropha curcas is a drought tolerant species and with great economic potential for the Brazilian semiarid region

Eucalyptus CLONES VERSUS CELLULOSIC PULP PRODUCTION

A qualidade da madeira \ue9 definida pelas combina\ue7\uf5es entre as diversas caracter\uedsticas intr\uednsecas da \ue1rvore em fun\ue7\ue3o do seu uso. O objetivo do presente estudo foi avaliar essas caracter\uedsticas na madeira de clones de Eucalyptus visando \ue0 produ\ue7\ue3o de polpa celul\uf3sica kraft de qualidade. Foram usados 15 clones, duas \ue1rvores de cada clone, num total de trinta \ue1rvores, todos com idades de 5,8 anos. As caracter\uedsticas avaliadas na madeira foram densidade b\ue1sica, dimens\uf5es das fibras (comprimento da fibra, espessura de parede, di\ue2metro do l\ufamen) e composi\ue7\ue3o qu\uedmica (teor de celulose, lignina, hemicelulose, extrativos e cinzas). Foram realizados quatro cozimentos Kraft para cada \ue1rvore, utilizando diferentes cargas de \ue1lcali ativo, para estabelecer a curva de deslignifica\ue7\ue3o da amostra. Essas cargas de \ue1lcali foram selecionadas ap\uf3s realiza\ue7\ue3o de cozimentos explorat\uf3rios, objetivando obten\ue7\ue3o de n\ufamero kappa pr\uf3ximo a 18 na parte mediana da curva. Nos cozimentos, foram avaliados o rendimento depurado, a viscosidade da polpa celul\uf3sica e o \ue1lcali consumido. Os resultados de rendimento variaram de 43,4 a 52,0 %, o teor de \ue1lcali ativo utilizado de 17,5 a 23,4 %, o \ue1lcali consumido de 15,5 a 20,0% e a viscosidade de 19,9 a 61,4 cP.The wood quality is defined by combining several intrinsic characteristics of the tree to its use. This research aimed to evaluate some of the wood characteristics of Eucalyptus clones and its performance in kraft pulping. Fifteen clones, 5.8 years-old were used, two trees from each clone, totaling thirty trees. The evaluated wood characteristics were: basic density, fiber dimensions (fiber length, wall thickness, lumen diameter) and chemical composition (cellulose, lignin, hemicelluloses, extractives and ash contents). Four samples were cooked at the laboratory for each tree, using different active alkali, to establish the delignification curve. These alkali loads were selected after exploratory cooking to obtain an eighteen kappa number at the medium point of the curve. In the cooking were appraised the screened, the pulp viscosity and consumed alkali. The yield results varied from 43.4 to 52.0%, the active alkali from 17.5 to 23.4%, the consumed alkali from 15.5 to 20.0% and the pulp viscosity from 19.9 to 61.4 cP