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Se analizó de forma perceptual la transferencia de conocimiento en tecnología de la madera en instituciones educativas estatales de Costa Rica. Se realizaron capacitaciones activo-pasivas en temas de secado, preservado y calidad de la madera, llevando a cabo tres evaluaciones de aprendizaje (precurso, postcurso y 30 semanas luego del postcurso). Con estas se valuó la percepción, conocimiento adquirido y limitaciones de los sistemas empleados. Se obtuvo una gran similitud entre las temáticas de secado y preservado con conocimientos previos superiores al 65 %, aprendizajes del 85 % y retenciones de conocimiento del 75 %; caso contrario se evidenció con la temática de calidad, la cual presentó un conocimiento previo del 20 %, aprendizaje del 83.5 % y retención del 75.6 %; los temas de secado y preservado mostraron la mejor percepción, considerados como simples, aplicables, útiles y entendibles; mientras que el tema de calidad se consideró complicado, complejo, inaplicable pero útil. Finalmente, se encontró que el aprendizaje de secado y preservado debe ser una combinación de 50 %-50 % entre teoría-práctica; mientras la calidad debería ser 25 %-75 % teoría-práctica.

The influence of climatic and site fertility conditions affect wood quality from fast growing trees. The change in tree diameter, thickness of sapwood, heartwood percentage and bark and pith tissue, physical and mechanical properties, resistance to termite attack and the presence of drying defects on lumber boards were evaluated. Four teak trees (Tectona grandis L.f.) from fast growing plantations in Costa Rica were selected for the study. Teak trees of 11 years old growing in two climatic conditions and two fertility types (high and low fertility) in Costa Rica were studied. The results showed that tree diameter, sapwood thickness, pith diameter and its percentage were higher in the climate with more rainfall and greater fertility. However, the percentage of heartwood and bark were higher at low fertility sites with less rainfall. It was also observed that only sites with low fertility produce modifications in specify gravity, fiber saturation point, initial moisture content, MOR in flexion in green and dry condition, MOE in bending and resistance to termite attack. Incidence and magnitude of defects increased with drying, and were mainly affected when wood comes from younger trees from high fertility sites and growing in tropical moist forest climate. © 2015, Indian Academy of Wood Science.

Blue stain in Pinus radiata D. Don wood is predominantly caused by Ophiostoma genus fungi. Stained wood causes significant economic losses to forestry and timber industries. Currently, different chemical fungicides are used to prevent the occurrence of blue stain fungi. However, recent reports have questioned the environmental friendliness of these fungicides. For this reason, the use of biological control, in particular with albino strains of the Ophiostoma genus, appears to be an environmentally safe and a technically feasible alternative to work with. The potential field application of this technology would use a formulation containing the albino fungus-the bioactive ingredient- in its yeast like form. However, some Ophiostoma strains cultures present a marked filamentous morphology in liquid culture medium, affecting the efficiency in the production of the bioactive ingredient. The hypothesis of this work presumed the possibility to control the morphology of Ophiostoma cultures, through the modification of growth conditions in liquid medium. The effect of inoculum size, growth temperature and agitation rate on the morphology of PcF2A29 Ophiostoma piceae and FlF1A55 Ophiostoma floccosum albino strains in liquid culture medium, was studied. A 23 factorial design was employed. The results showed that the initial inoculum size had a statistically significant effect on yeast-like growth morphology in both strains, whereas the temperature only produced a significant effect in PcF2A29 O. piceae strain. Blue stain in Pinus radiata D. Don wood is predominantly caused by Ophiostoma genus fungi. Stained wood causes significant economic losses to forestry and timber industries. Currently, different chemical fungicides are used to prevent the occurrence of blue stain fungi. However, recent reports have questioned the environmental friendliness of these fungicides. For this reason, the use of biological control, in particular with albino strains of the Ophiostoma genus, appears to be an environmentally safe and a technically feasible alternative to work with. The potential field application of this technology would use a formulation containing the albino fungus-the bioactive ingredient- in its yeast like form. However, some Ophiostoma strains cultures present a marked filamentous morphology in liquid culture medium, affecting the efficiency in the production of the bioactive ingredient. The hypothesis of this work presumed the possibility to control the morphology of Ophiostoma cultures, through the modification of growth conditions in liquid medium. The effect of inoculum size, growth temperature and agitation rate on the morphology of PcF2A29 Ophiostoma piceae and FlF1A55 Ophiostoma floccosum albino strains in liquid culture medium, was studied. A 23 factorial design was employed. The results showed that the initial inoculum size had a statistically significant effect on yeast-like growth morphology in both strains, whereas the temperature only produced a significant effect in PcF2A29 O. piceae strain.