Silvicultura en Bosques Nativos vol. 1

39 Plantas de Nothofagus mediterráneos para restauración SUMMARY Nothofagus alessandrii and Nothofagus glauca are two characteristic species from theMediterranean area of Chile, which have conservation problems. Propagation and seedling cultivation in nursery are important tools to consider in the restoration and reforestation of forests with these species. Therefore, background information it is given to guide the decision making, considering the importance of the seedling attributes in the subsequent performance of plants in a Mediterranean environment. Both species can be propagated sexually and asexually, although it is more difficult to N. alessandrii , especially in the agamic propagation. The internal dormancy of the seeds of both species can be overcome by a cold stratification treatment (4-8 weeks) or soaking them in gibberellic acid (GA 3 ~200 mg/L). Using vegetative propagation by cuttings, for both species is possible to obtain a rooting ranging from 0 to 100 %, if juvenile material harvested in the vegetative growth period is utilized. Additionally, a marked influence of the mother tree (ortet) from which the ramet comes from have been observed. It is also important the use of indole butyric acid (5-10 g/kg -1 ). For the seedling nursery cultivation is necessary to consider a horizontal shading to protect the plants from the direct sunlight. In general, after one nursery season, plants with functional characteristics for reforestation, according to their morphological attributes and quality indexes, can be produced. It is still necessary to investigate how some treatments performed in the nursery, like fertilization, can affect the quality of plants, especially on their physiological attributes, as well as to assess their subsequent performance in the field. Key words : ruil, hualo, propagation, nursery cultivation, attributes. 3.1 Introducción La zona mediterránea de Chile, ubicada entre las regiones de Valparaíso y del Biobío, concentra la mayor biodiversidad en el país, con una rica flora y fauna autóctona (Myers et al . 2000). Los bosques caducifolios de esta zona están adaptados a los períodos secos prolongados del verano y cumplen un rol muy importante en la conservación de agua y suelo orgánico, en el ciclo biogeoquímico del carbono, y ofrecen una gran variedad de nichos ecológicos y hábitat a la flora, fauna y microbiota asociada (Arroyo et al . 1996). Sin embargo, esta zona ha estado sujeta a una permanente presión de origen antropogénico, especialmente durante los dos últimos siglos. Una constante de estos paisajes ha sido su transformación debido a la presencia del fuego en forma recurrente, a la deforestación para habilitar terrenos destinados a la agricultura y, más recientemente, con el objeto de establecer plantaciones con especies de rápido crecimiento. Estos disturbios han traído como