ABSTRACT Eucalyptus is a species of the most cultivated in the national scope, whose wood is widely used in the manufacture of furniture and other derived products. However, it is subjected to variations due to changes in moisture and other factors. To minimize such variations, some treatments were studied in a non-environmentally aggressive manner. This work analyzed the physical and chemical properties of wood of hybrid clones of Eucalyptus urograndis, “in natura” and thermally modified at temperatures of 140, 160, 180, 200 and 220°C, with 8.5 years of age, planted in Buri-SP, Brazil. The physical characterization was performed according to Brito, Garcia and Bortoletto (2006) and Brazilian Association of Technical Standards (1997), and the chemical characterization according to Technical Association of the Pulp and Paper Industry (1999). Through statistical analysis of factorial regression with significance of 5%, the clone factor did not cause interference in the analyzed properties; the variation that occurred was due to the temperature used; the hemicellulose was the main chemical property affected by the temperature; the most interesting treatments were those performed up to 180°C, since they did not compromise much the chemical properties of the wood and, consequently, would not affect so much their physical and mechanical properties.

RESUMO O eucalipto é uma espécie das mais cultivadas no âmbito nacional, cuja madeira é amplamente utilizada na fabricação de móveis e outros produtos derivados. Entretanto, ela está sujeita a variações por conta de mudanças na umidade e outros fatores. Para minimizar tais variações, estudaram-se alguns tratamentos de forma pouco agressiva ao meio ambiente. Assim, este trabalho analisou as propriedades físicas e químicas da madeira de clones híbridos de Eucalyptus urograndis, in natura e termicamente modificada nas temperaturas de 140, 160, 180, 200 e 220°C, com 8,5 anos de idade, plantados em Buri-SP, Brasil. A caracterização física foi realizada segundo Brito, Garcia e Bortoletto (2006) e normas da Associação Brasileira de Normas Técnicas (1997), e a caracterização química segundo as normas Technical Association of the Pulp and Paper Industry (1999). Através de análises estatísticas de regressão fatorial com significância de 5%, o fator clone não causou interferência nas propriedades analisadas; a variação que ocorreu foi por conta da temperatura utilizada; a hemicelulose foi a principal propriedade química afetada por conta da temperatura; os tratamentos mais interessantes foram os realizados até 180 °C, uma vez que não comprometeram muito as propriedades químicas da madeira e, consequentemente, não afetariam tanto suas propriedades físicas e mecânicas.

ABSTRACT: The biotrophic fungus Hemileia vastatrix causes coffee leaf rust (CLR), one of the most devastating diseases in Coffea arabica . Coffee, like other plants, has developed effective mechanisms to recognize and respond to infections caused by pathogens. Plant resistance gene analogs (RGAs) have been identified in certain plants as candidates for resistance ( R ) genes or membrane receptors that activate the R genes. The RGAs identified in different plants possess conserved domains that play specific roles in the fight against pathogens. Despite the importance of RGAs, in coffee plants these genes and other molecular mechanisms of disease resistance are still unknown. This study aimed to sequence and characterize candidate genes from coffee plants with the potential for involvement in resistance to H. vastatrix . Sequencing was performed based on a library of bacterial artificial chromosomes (BAC) of the coffee clone ‘Híbrido de Timor’ (HdT) CIFC 832/2 and screened using a functional marker. Two RGAs, HdT_LRR_RLK1 and HdT_LRR_RLK2, containing the motif of leucine-rich repeat-like kinase (LRR-RLK) were identified. Based on the presence or absence of the HdT_LRR_RLK2 RGA in a number of differential coffee clones containing different combinations of the rust resistance gene, these RGAs did not correspond to any resistance gene already characterized (SH1-9). These genes were also analyzed using qPCR and demonstrated a major expression peak at 24 h after inoculation in both the compatible and incompatible interactions between coffee and H. vastatrix . These results are valuable information for breeding programs aimed at developing CLR-resistant cultivars, in addition to enabling a better understanding of the interactions between coffee and H. vastatrix .

RESUMO As características silviculturais e tecnológicas favoráveis da espécie Calophyllum brasiliense Camb. têm levado ao surgimento de plantios comerciais. De modo geral, a literatura apresenta somente dados médios e gerais sobre algumas variáveis desta espécie, não informando dados específicos a determinadas variáveis antecessoras ao momento do estudo tecnológico, como idade, espaçamento, entre outros, talvez porque se trata de uma espécie de floresta nativa. Dada a lacuna existente quanto à caracterização da madeira de guanandi, o objetivo deste trabalho foi estudar quantitativamente: (i) a variação estrutural morfológica das principais células do lenho, e (ii) a delimitação entre madeira juvenil e adulta, para a espécie proveniente de plantio puro, cujas variáveis antecessoras são conhecidas. Foram amostradas cinco espécimes, dentro de uma população de 135 árvores, com 13 anos de idade e espaçamento 4,0 m x 2,5 m. Os resultados indicaram valores médios de 1134; 21,02; 12,88 e 4,07 μm para o comprimento, largura, diâmetro do lume e espessura média da parede das fibras, respectivamente. A madeira de guanandi com 13 anos de idade foi caracterizada como juvenil.

ABSTRACT Favorable silvicultural and technological characteristics of the species Calophyllum brasiliense Camb. have led to the emergence of commercial plantations. Scientific literature offers only medium and general data on some variables of this species, not reporting specific variables prior to the time of the study, such as age, spacing, among others, perhaps because the wood is mostly from native forests. Given the knowledge gap regarding the characterization of guanandi wood, the aim of this work was to quantitatively study: (i) the morphological structural variation of the wood cells, and (ii) the distinction between juvenile and mature wood, for the species from a pure plantation, whose growth history are known. Five specimens were sampled, within a population of 135 trees, with 13 years of age and 4.0 x 2.5 m spacing. The results indicated average values of 1134, 21.02, 12.88 and 4.07 μm for the length, width, and diameter of the lumen and mean wall fiber thickness, respectively. 13-years-old guanandi wood was characterized as juvenile.

O Eucalyptus grandis é uma das espécies mais cultivadas no Brasil devido à sua produtividade e qualidade da madeira. Avaliaram-se o efeito da aplicação de lodo de esgoto tratado (0 a 40 t ha-1 base seca) e uma dose de adubo mineral nos atributos físicos e químicos da madeira de Eucalyptus grandis de árvores com cinco anos de idade, no Município de Itatinga, São Paulo, Brasil. O tipo de solo foi caracterizado como Latossolo Vermelho-Amarelo Distrófico (argila = 120 g kg-1 na camada de 0-20 cm) e o clima, como mesotérmico úmido (Cwa), segundo a classificação de Köeppen. O delineamento experimental foi o de blocos ao acaso, com seis tratamentos e quatro repetições. O diâmetro à altura do peito (DAP), a altura das árvores e o volume de madeira foram obtidos em todas as parcelas de oito árvores com DAP na classe de maior freqüência. As caracterizações físicas e químicas da madeira foram realizadas de acordo com as normas da ABTCP, TAPPI e ABNT. O lodo de esgoto diminuiu a densidade básica da madeira, mas não afetou os teores de celulose, lignina, extrativos e o poder calorífico da madeira. O decréscimo de densidade da madeira pela adubação com lodo de esgoto foi compensado pela maior produtividade de madeira.

Eucalyptus grandis is the most planted species in Brazil due to its productivity and quality of wood. The effect of growing rates of treated sewage sludge (0 to 40 Mg. ha-1 dry base) and one rate of mineral fertilizer on physicochemical attributes of Eucalyptus grandis wood were evaluated. The studied trees were five years old. The experimental area is located in the municipality of Itatinga, State of São Paulo, Brazil. The soil was characterized as a Dystrophic Red-Yellow Latosol (clay = 120 g kg-1 at 0-20 cm layer). The climate was characterized as a humid mesothermic (Cwa), according to Köeppen classification. The plots were established in a randomized complete block design, with 6 treatments and 4 replicates. The height, diameter at breast height (DBH) and solid wood volume was measured in all plots. Samples of 8 trees belonging to the most frequent DBH were collected. Five disks (4 cm thick) were removed from each tree at 0, 25, 50, 75 and 100% of the commercial height. The physicochemical characterizations were carried out according to the norms of the Brazilian Pulp and Paper Technical Associations. The sewage sludge reduced the basic density of wood. The contents of cellulose and lignin extracts and calorific power of wood were not changed. The decrease in wood density promoted by sewage sludge application was compensated by the increase in wood growth.