Produção de painéis compensados com madeira de bolaina (Guazuma crinita Mart) colados com resinas de urea-formaldeído e fenol-frmaldeído para uso interno e externo. Esta pesquisa teve como objetivo avaliar a qualidade de painéis compensados produzidos com bolaina (Guazuma crinita Mart.) e lupuna (Ceiba pentandra [L] Gaertn) como espécies de referência. Os painéis foram produzidos com dimensões de 600 mm x 600 mm x 10 mm (cinco camadas), segundo arranjo fatorial (3x2), três composições de lâminas (bolaina, lupuna e bolaina/lupuna) e duas formulações para cada adesivo (A: 45,9% e B: 35,8% dos sólidos totais) para ureia-formaldeído; (B: 40% e C: 34,3%) para fenol-formaldeído, gramatura de 380 g/m 2 em linha de cola dupla, pressão específica de 0,6 MPa, temperatura de 115 ºC e tempo de prensagem de 8 minutos para ureiaformaldeído; e 1,0 MPa, 130 °C e 6 minutos de tempo de prensagem para fenol-formaldeído. O efeito da formulação não influencia significativamente nas propriedades físicas e mecânicas dos painéis, o que representa um aspecto importante do ponto de vista econômico. No entanto, a interação da formulação com as espécies usadas na composição do painel influenciou significativamente nessas propriedades. A resistência ao cisalhamento e o percentual de ruptura da madeira dos painéis atendem aos requisitos mínimos da norma EN 314-2 (1993) para painéis de uso interno e externo, razão pela qual se conclui que a espécie Guazuma crinita Mart. atende à viabilidade técnica requerida para produzir painéis compensados para uso interno e externo. Palabras-chave: compensados, lâminas de madeira, formulação de cola, resistência da linha da cola, pressão específica.

Lily (genus Lilium) is one of the most important flowers for bulb and cut flower production in the world. Lilium rubellum Baker is a native species of Japan that exhibits early flowering, is pink coloured, and possesses a pleasant fragrance, which makes it an important genetic resource for breeding lilies. In this work, the genetic diversity of L. rubellum was studied among three natural populations located in Fukushima Prefecture, Japan, which have been designated as the Mt. Azuma, Nango and Atsushio-kano populations. A total of 31 accessions collected in 1997 were analysed using Random Amplified Polymorphic DNA (RAPD) markers. Eighteen decamer primers produced 98% polymorphic RAPD bands; furthermore, 11 of the 18 primers produced 10 or more polymorphic bands with a mean per primer Polymorphic Information Content of 0.382. Among the three populations, the mean Shannon index, Nei´s gene diversity and percentage of polymorphic loci were 0.2749, 0.4099 and 76.7%, respectively. These data revealed that there is a high genetic diversity within all the populations. Analysis of the three genetic diversity indices within populations showed that the Nango population had the highest genetic diversity, whereas the Atsushio-kano population had the lowest. An unweighted pair group method with arithmetic mean dendrogram based on Jaccard´s similarity coefficient was constructed, and the three populations of L. rubellum collected in the Fukushima prefecture were clearly differentiated at 0.61 similarity index. The Nango and Mt. Azuma populations were genetically closer than the Atsushio-kano population. The analysis of molecular variance showed a 29.53% variance among the populations. This study revealed that there is high genetic diversity within populations and moderate genetic diversity among the three natural populations of L. rubellum Baker in the Fukushima Prefecture of Japan.

RESUMEN Se elaboraron tableros de partículas de tres capas, 12 mm de espesor y 0,65 g.cm -3 de densidad con madera de "bolaina" (Guazuma crinita Mart), de una plantación de cuatro años localizada en Neshuya, -Ucayali, Perú. Las partículas fueron encoladas con Urea Formaldehído. Se evaluaron las propiedades físicas y mecánicas de los tableros según la metodología propuesta por las Normas Europeas (EN). Los valores de masa específica y pH de la madera son los adecuados para la elaboración de tableros de partículas; el hinchamiento sin parafina a las 2 y 24 horas de inmersión en agua fue 26,45% y 36,40% respectivamente; con parafina a las 2 horas el hinchamiento disminuyo en un 5.29% sin embargo a las 24 horas de inmersión en agua el hinchamiento se incrementó en 1.88%. La flexión estática promedio sin parafina fue de 15,55 MPa, valor cercano al encontrado con parafina. La tracción perpendicular promedio sin parafina fue de 0,97 MPa con un descenso de 15.46% cuando de utilizó parafina. La evaluación de los resultados obtenidos, permiten apreciar que es posible fabricar tableros de partículas con la madera bolaina de cuatro años de edad. Palabras claves: partículas de madera; tableros de partículas; urea formaldehido; parafina. Production of particleboards with Bolaina (Guazuma crinita Mart)from a four-year-old plantation ABSTRACT Production of particle boards with Bolaina (Guazuma crinita Mart) from a four-year-old plantation. Three-ply particle boards, 12 mm thick and 0,65 g.cm -³ of density, were made using wood (Guazuma crinita Mart), "bolaina", from a fouryear plantation located in Neshuya -Ucayali. The particles were glued with a formaldehyde urea. The physical and mechanical properties of the boards were evaluated according to the methodology proposed by the European Standards for each test. The values of the specific mass and pH of the wood are suitable for the manufacture of particle boards, swelling without paraffin at 2 and 24 hours of immersion in water was 26,45% and 36,40% respectively with paraffin at 2 hours the swelling decreased by 5.29% however at 24 hours of immersion in water the swelling increased by 1.88%. The mean static bending without paraffin was 15.55 MPa, a value close to that found with paraffin. The internal bond without paraffin was 0.97 MPa with a decrease of 15.46% when using paraffin. The evaluation of the results obtained shows that it is possible to manufacture particle boards use with 4-yearold bolaina.