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Axillary buds (2 ram) from 3-year-old Caricapubescens Lenn6 et Koch (highland papaya) fruit-bearing plants grown in the greenhouse were cultivated in N-N-medium supplemented with different growth regulators (naphthaleneacetic acid and indoleacetic acid in combination with Zeatin, benzyladenine, Kinetin and thidiazuron. Several responses were observed within 2-3 months; namely, sprouting of the preformed axillary buds, bud branching into multiple shoots, callus formation at the basal end of the explant and somatic embryogenesis in the preformed callus. Somatic embryogenesis was frequent in most of the tested growth regulator combinations, with the exception of thidiazuron which showed no effect. A much higher yield of somatic embryos could be obtained in suspensions. Somatic embryogenesis was enhanced by the occurence of adventive embryogenesis on single embryos as globular embryo clusters. This was observed in cell suspensions initially grown in a WPM-medium with 2,4-dichlorophenoxyacetic acid, or in combination with benzyladenine or zeatin, for 6 days, then maintained in a growth regulator-free medium under continuous agitation (50 RPM) on an orbital shaker for 3 months. Single cells grown in the absence of 2,4-dichlorophenoxyacetic acid did not initiate embryogenesis and de-differentiated into callus. Plantlets were recovered after transfer of mature embryos from cell suspensions into Magenta flasks. In a second subculture, adventitious embryogenesis occurred spontaneously in clusters at the globular embryo stage under the same growth conditions, yielding a high number of embryos. The culture conditions described above allowed initiation of a large number of somatic embryos directly from cell suspensions through adventive somatic embryogenesis and indirectly from callus on axillary buds.

In vitro shoot and root regeneration of 2-year-old Nothofagus alpina plants was achieved from several types of expiants cultured in vitro on a modified Woody Plant Medium formulation. Multiple shoot formation was obtained from leaf expiants using 0.45-2.27 μM thidiazuron and 0.0049-0.098 μM indolebutyric acid. Excised axillary buds formed shoots and roots in the presence of 0.0049 μM benzyladenine and 2.46 μM indolebutyric acid, or in the absence of plant growth regulators. Nodal sections rooted when 2.46 μM indolebutyric acid at was supplied in the medium. Subcultured shoots originating from nodal sections showed a high regeneration rate through multiple shoot and root formation.

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RESUMENMyrcianthes coquimbensis es una especie endémica de Chile en peligro de extinción, con una distribución restringida en la costa de la Región de Coquimbo. En la actualidad su hábitat está siendo fuertemente impactado por desarrollos inmobiliarios. La especie presenta valor ornamental; sin embargo, desde el punto de vista paisajístico es poco conocido. En esta investigación se estudió la propagación por semillas y vegetativa por esquejes, con fines de conservación ex situ. En ensayos de germinación se encontró que la cinética de este proceso varió significativamente según la época de siembra (invierno o verano). Así después de 90 días de siembra se observó un 51% de germinación en verano, mientras en invierno sólo alcanzó el 29%. También se observó un efecto inhibitorio del pericarpio sobre la germinación, disminuyendo un 50% la germinación. La incubación de semillas en GA 3 (24 h) incrementó el porcentaje de germinación dependiendo de la dosis. Se realizaron ensayos de enraizamiento de esquejes con tratamientos de AIB en cama fría y cama caliente. En cama fría se observó una baja respuesta (8,44%), y no mostró relación con los tratamientos de AIB. En contraste a lo anterior, en cama caliente el enraizamiento alcanzó un 33% con aplicación de 3.000 ppm de AIB. El mejor resultado de enraizamiento se obtuvo con material proveniente de plantas mantenidas en condiciones de vivero. PALABRAS CLAVE:Myrtaceae, flora amenazada, endemismo chileno, conservación ex situ. ABSTRACTMyrcianthes coquimbensis is an endangered species, endemic from Chile where it has a restricted distribution in the coast of the Coquimbo Region. Nowadays its habitat is being heavily impacted by real estate development. This species has ornamental value, but is almost unknow from gardeners and landscapers. This work aims at contributing to Myrcianthes coquimbensis ex situ conservation by development of its propagation by both sexual and vegetative way. Germination tests shown that the kinetics of this process varied significantly according to the sowing season (winter or summer). After 90 days, emergence was of 51% in summer, while in winter it only reached 29%. The pericarp was found to have an inhibitory effect, decreasing germination by 50%. Incubation of seeds in GA 3 during 24 h increased the percentage of germination with a dose-dependent effect. Cutting-propagation assays were performed with AIB treatments in cold or warm bed. In cold bed, a poor response was obtained (8.44% of rooting), without influence of treatments. However, in hot bed, rooting reached 33% with application of (3,000 ppm). Best results were obtained when stems came from plants maintained under nursery conditions.

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SUMMARYThe National Forestry Corporation (CONAF) progresses in the implementation of the National Strategy for Climate Change and Vegetation Resources (ENCCRV). Under this context it is necessary to know the amount of carbon that can be contained by the Mediterranean Forest. The aim of this work was to development allometric functions to estimate carbon content in four species of the Chilean Mediterranean Forest: quillay, peumo, espino and litre. Nineteen sampling places, between Valparaíso and Biobío regions of the country, were selected for the cutting of 328 trees. Regarding the distribution of green weight between components, moisture content and basic density in espino and litre were similar, though different from quillay and peumo, which in turn showed similar levels to each other. According to these results, it could mean that there is influence of Mediterranean status over these variables. Carbon content in four species was around 49 % of the total dry biomass. Models found provided similar settings to most of those already published for these species biomass, with the advantage that only one allometric variable is required for what is proposed in this work. Quillay, peumo and espino had R 2 > 0.92 while espino had R 2 = 0.87.Key words: allometric functions, carbon, forest mediterranean. RESUMENLa Corporación Nacional Forestal (CONAF) progresa en la ejecución de la Estrategia Nacional de Cambio Climático y Recursos Vegetacionales (ENCCRV), bajo este contexto es necesario conocer los contenidos de carbono que pueden contener el Bosque Mediterráneo. El objetivo de este trabajo fue la elaboración de funciones alométricas para estimar contenido de carbono en cuatro especies del Bosque Mediterráneo Chileno: quillay, peumo, espino y litre. Se abarcaron 19 zonas de muestreo distribuidas entre las regiones de Valparaíso y del Biobío con un total de 328 árboles procesados. Para la distribución de peso verde entre componente, para el contenido de humedad, y para la densidad básica, litre y espino fueron similares y diferentes a quillay y peumo, que a su vez mostraron niveles similares entre sí. Ello podría significar que existe influencia de la mediterraneidad en estas variables. El contenido de carbono para las cuatro especies oscila en torno a 49 % de la biomasa seca total. Los modelos encontrados ofrecieron ajustes similares a la mayoría de los ya publicados para biomasa de las especies, con la ventaja que los propuestos en este trabajo, aportarán la componente carbono y sólo requieren una variable alométrica. Para quillay, peumo y espino el R 2 encontrado fue mayor a 0,92, mientras que para litre fue de 0,87.Palabras clave: funciones alométricas, carbono, bosque mediterráneo. INTRODUCCIÓNEn Chile existe profusa información de funciones alométricas para biomasa de las especies arbóreas de los bosques templados (Schlegel 2001, Gayoso y Guerra 2005, Picard et al. 2012. Para las especies arbóreas del bosque mediterráneo, en cambio, los trabajos son más bien escasos. CONAF (2013) destaca la abundancia de publicacio...