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ilustraciones, fotografías, tablas La miel sufre un proceso de cristalización natural al ser una solución sobresaturada en glucosa. La velocidad de este proceso depende esencialmente de su composición química, aunque los procesos tecnológicos (tratamientos físicos y térmicos) también son importantes. La miel proveniente de plantaciones forestales de Acacia mangium en Vichada es un producto que tiende a formar rápidamente cristales de dimensiones visibles, lo que afecta su comercialización. La cristalización inducida o granulación es una alternativa para controlar la tasa de crecimiento (tamaño y forma cristalina) y de nucleación (número de cristales). En ella se adiciona a la miel una sustancia semilla o inoculante (azúcares o miel) con cristales de menores dimensiones y se hace agitación con el fin de conferirle características físicas y texturales deseables. El objetivo fue evaluar el proceso de cristalización inducida en este tipo de miel. Inicialmente se analizó la correlación entre variables de respuesta actividad de agua, turbidez (absorbancia a 660 nm), color (L*, a*, b*, matiz, croma) y textura (firmeza y cohesividad). Posteriormente se optimizó el proceso de granulación para poder lograr un producto con una similitud en las variables medidas respecto a la miel empleada como "testigo comercial" utilizando un diseño Box-Behnken, con parámetros el tiempo (1, 5 y 10 min) y velocidad de agitación (250, 500 y 750 rpm) y porcentaje de semilla inoculada (0, 5 y 10%). Además, se determinaron las diferencias respecto a la miel sin agitación y sin inoculación (testigo control o cristalización natural no dirigida) y a la miel usada como semilla (testigo comercial y con las propiedades organolépticas deseadas). La actividad de agua de todas las muestras aumenta con el tiempo con valores entre 0,573±0,011 y 0,613±0,009, estabilizando su valor desde el día 15 de almacenamiento. Se observaron variaciones importantes en los valores de los componentes cromáticos a* y b* entre los tratamientos con una proporción elevada de inoculante en comparación con las muestras que tenían una cantidad menor de miel semilla añadida. De la misma forma, la turbidez de los tratamientos (pasados 15 días de almacenamiento a temperatura controlada de 14±1ºC) fue en promedio 2,72±0,028 unidades de absorbancia a 660 nm, tendiendo a tener valores similares a los de la miel con cristalización natural. La firmeza y la cohesividad de las muestras sin adición de miel semilla tenían un valor de hasta dos órdenes de magnitud inferiores en comparación al resto de tratamientos. Por otro lado, se encontró una correlación significativa entre variables como la absorbancia con la firmeza (r2=0,75***) o la cohesividad (r2=0,74***), mostrando cómo el cambio en las propiedades texturales está relacionado con la formación de cristales medida por la turbidez. Además, el factor semilla es mucho más significativo que la velocidad o el tiempo de agitación, con lo cual implica que en la granulación en esta miel es más importante la velocidad de nucleación que la de crecimiento. Con el PCA se establecieron tres componentes: el primero está más fuertemente influenciado por las variables texturales y la actividad de agua, y explica el 43,9% de la varianza observada; el segundo componente está más definido por las coordenadas de color (24,6%). Al realizar la optimización se encontró que el procedimiento óptimo estaba definido por tiempo de 2,5 min, velocidad de 850 rpm y porcentaje de semilla del 7%. Una vez definido el tratamiento óptimo se procedió a evaluar la variación de propiedades texturales, colorimétricas, micromorfológicas, calorimétricas y reológicas durante el tiempo de almacenamiento a 14±1ºC y en oscuridad. En este caso, la actividad de agua (de 0,546±0,001 en el día inicial a 0,557± 0,002 en el 18), la turbidez (absorbancia de 3,27±0,01 en el día 18), el diámetro ponderado medio, la firmeza (30.967,0±2400,0 g en el día 15) y la cohesividad (86.411,0±9465,0 g s en el día 15) aumentaron con el tiempo. Las coordenadas CIELab y los índices de color no presentaron diferencias significativas excepto el ángulo de matiz que aumentó. La entalpía de la miel aumentó a 550 kW/g en el último día de evaluación con temperaturas de fusión entre 40 y 60°C. La reología siguió los comportamientos esperados para el módulo de pérdida (G”) y almacenamiento (G’). Con todo lo anterior, se observó que en miel de Acacia mangium la cristalización está controlada por el crecimiento, de tal manera que aumentando la cantidad de núcleos mejora las propiedades sensoriales. (Texto tomado de la fuente). Honey experiments a natural crystallization process as it is a supersaturated glucose solution. The speed of this process essentially depends on its chemical composition, although the technological processes (physical and thermal treatments) are also important. Honey from Acacia mangium forest plantations in Vichada is a product that tends to quickly form crystals of visible dimensions, which affects its commercialization. Induced crystallization or granulation is an alternative to control the rate of growth (size and crystalline shape) and nucleation (number of crystals). In the commercial way, a seed or inoculant substance (sugars or honey) with smaller crystals is added to the honey and agitation is done in order to confer desirable physical and textural characteristics. The objective was to evaluate the crystallization process induced in this type of honey. Initially, the correlation between response variables water activity, turbidity (absorbance at 660 nm), color (L*, a*, b*, hue, chroma) and texture (firmness and cohesiveness) was analyzed. Subsequently, the granulation process was optimized in order to achieve a product with similar measured variables with respect to the honey used as "commercial control" using a Box-Behnken design, with parameters of time (1, 5 and 10 min) and the shaking speed (250, 500 and 750 rpm) and percentage of inoculated seed (0, 5 and 10%). In addition, the differences were determined with respect to honey without agitation and without inoculation (control control or undirected natural crystallization) and honey used as seed (commercial control and with the desired organoleptic properties). The water activity of all the samples increases with time with values between 0.573±0.011 and 0.613±0.009, stabilizing its value from day 15 of storage. Significant variations in the values of the chromatic components a* and b* were observed between the treatments with a high proportion of inoculant compared to the samples that had a lower amount of honey added. In the same way, the turbidity of the treatments (after 15 days of storage at a controlled temperature of 14±1ºC) was on average 2.72±0.028 absorbance units at 660 nm, tending to have values similar to those of honey with natural crystallization. The firmness and cohesiveness of the samples without the addition of seed molasses had a value of up to two orders of magnitude lower compared to the rest of the treatments. On the other hand, a significant correlation was found between variables such as absorbance with firmness (r2=0.75***) or cohesiveness (r2=0.74***), showing how the change in textural properties is related to crystal formation as measured by turbidity. In addition, the seed factor is much more significant than the speed or the agitation time, which implies that in the granulation in this honey the speed of nucleation is more important than that of growth. With the PCA, three components were established: the first is more strongly influenced by textural variables and water activity, and explains 43.9% of the observed variance; the second component is more defined by color coordinates (24.6%). When performing the optimization, it was found that the optimal procedure was defined by a time of 2.5 min, a speed of 850 rpm and a seed percentage of 7%. Once the optimal treatment was defined, we proceeded to evaluate the variation of textural, colorimetric, micromorphological, calorimetric and rheological properties during the storage time at 14±1ºC and in the dark. In this case, the water activity (from 0.546±0.001 on the initial day to 0.557±0.002 on the 18th), the turbidity (absorbance of 3.27±0.01 on the 18th day), the mean weighted diameter, the firmness (30,967.0±2400.0 g on day 15) and cohesiveness (86,411.0±9465.0 g s on day 15) increased over time. The CIELab coordinates and the color indices did not present significant differences except for the hue angle that increased. The enthalpy of honey increased to 550 kW/g on the last day of evaluation with melting temperatures between 40 and 60°C. The rheology followed the expected behaviors for the modulus of loss (G") and storage (G'). With all of the above, it was observed that crystallization in Acacia mangium honey is controlled by growth, in such a way that increasing the number of nuclei improves sensory properties. Maestría Magíster en Ciencia y Tecnología de Alimentos

Quality Planting Material (QPM) may be defined as "the production of uniform, healthy, disease-free planting material raised through seed or vegetative methods with an overall goal to raise the physiological and phytosanitary quality of the plant and make it available to stakeholders to increase productivity." Particularly for economically relevant timber species, quality plant material (QPM) from agroforestry species is necessary. To produce high-quality planting materials on a large scale, it is important to have a thorough understanding of seed and nursery processes.&nbsp

RESUMEN El género Paraburkholderia comprende más de 100 especies, las cuales pueden ser aisladas de diversos ambientes como plantas, suelos agrícolas, suelos volcánicos e incluso, a partir de cuerpos de agua. Existen pocos estudios en nuestro país que reportan el aislamiento de miembros pertenecientes a este género. En éste trabajo, se estudió la posición taxonómica de siete cepas rizosféricas pertenecientes al grupo de Burkholderia sensu lato, aisladas en el municipio de Chignahuapan del estado de Puebla de árboles maderables como el pino y de plantas silvestres como los helechos y las bromelias, utilizando un enfoque taxonómico polifásico. Con base en las secuencias de los genes ARNr 16S, atpD y recA se confimó que todas las cepas pertenecen al género Paraburkholderia y que GB45, GB51, GB53, GB62, GB152 y GB203 forman un clúster con Paraburkholderia sediminicola y Paraburkholderia aspalathi, con excepción de la cepa GB190, la cual podría representar una nueva especie al separarse de este grupo como lo demuestran los árboles filogenéticos. Con respecto a la caracterización fenotípica, las siete cepas de Paraburkholderia mostraron un crecimiento óptimo a una temperatura de 35 °C y un pH 6 en ausencia de NaCl. La tolerancia a distintas concentraciones de metales pesados (Co, Pb, Mo, Ni, Zn y V) fue diversa, así como en las pruebas de antibióticos. La cepa GB51 fue la única que creció en presencia de zinc hasta 200 ppm y en vanadio hasta 50 ppm, mientras que la cepa GB190 no creció a 39 °C y a un pH 4 pero fue la única cepa que si lo hizo en presencia de gentamicina a una concentración de 1 µg/mL y kanamicina a 2.5 µg/mL, estas características fueron las que la diferenciaron del resto de los aislamientos. ABSTRACT The genus Paraburkholderia comprises more than 100 species, isolated from various environments such as plants, agricultural soils, volcanic soils, and even water bodies. Few studies in our country report the isolation of members belonging to this genus. In this work, we focus on the taxonomic position of seven rhizospheric strains belonging to the Burkholderia sensu lato group, all of them were isolated from timber trees such as pine and wild plants such as fern and bromeliads, in the municipality of Chignahuapan situated in the state of Puebla using an approach polyphasic taxonomic. Based on the sequences analysis of the 16S rRNA, atpD, and recA genes confirmed that all the strains belong to the genus Paraburkholderia, even GB45, GB51, GB53, GB62, GB152, and GB203 form a cluster with Paraburkholderia sediminicola and Paraburkholderia aspalathi, except for the GB190 strain, which might represent a new species of this genus because it is separated from this group, as shown by phylogenetic trees. Regarding the phenotypic characterization, the seven strains showed an optimal growth at at 35 °C and pH 6.0 in the absence of NaCl. The ability to tolerate different heavy metal concentrations (Co, Pb, Mo, Ni, Zn, and V) and antibiotics concentrations (ampicilin, gentamicin, tetracyclin, kanamycin, and chloramphenicol) was diverse. Only the GB51 strain grew in the presence of zinc (≤200 ppm) and vanadium (≤50 ppm). The GB190 strain was not able to grow at 39 °C and pH 4.0 but it was the only strain resistant to gentamicin (1 µg/mL) and kanamycin (2.5 µg/mL), characteristics that also differentiated it from the rest of the isolates., {"references":["Rosselló-Mora, R., Amann, R. The species concept for prokaryotes. FEMS microbiology reviews. 2001;25(1), 39-67.","Caballero-Mellado J, Onofre-Lemus J, Estrada-De Los Santos P, Martínez-Aguilar L. The tomato rhizosphere, an environment rich in nitrogen-fixing Burkholderia species with capabilities of interest for agriculture and bioremediation. Appl Environ Microbiol. 2007;73(16):5308–19.","Estrada-de los Santos P, Palmer M, Chávez-Ramírez B, Beukes C, Steenkamp ET, Briscoe L, et al. Whole genome analyses suggests that Burkholderia sensu lato contains two additional novel genera (Mycetohabitans gen. nov., and Trinickia gen. nov.): Implications for the evolution of diazotrophy and nodulation in the Burkholderiaceae. 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Las comunidades vegetales pos fuego del NO de la Patagonia, constituidas preferentemente por especies como la laura (Schinus patagonicus), el retamo (Diostea juncea), el ñire (Nothofagus antárctica) y el radal Lomatia hirsuta) (y a veces acompañadas también por el maitén, Maytenus boaria); son ampliamente empleadas para la extracción de leña. Las extracciones se realizan comúnmente en baja intensidad, seleccionando los fustes considerados más convenientes, por calidad o tamaño, aunque sin criterios de sostenibilidad. El resultado es el empobrecimiento paulatino del bosque: la reducción de la densidad y la reducción o pérdida de los componentes más valorados. Estación Experimental Agropecuaria Bariloche Fil: Varela, Santiago Agustin. Instituto Nacional de Tecnologia Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Grupo de Ecología Forestal; Argentina Fil: Rusch, Veronica Elena. Instituto Nacional de Tecnologia Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Grupo de Ecología Forestal; Argentina

Todo Madera publica en exclusiva este artículo sobre pino ponderosa, especie que acaba de ser incorporada en los Suplementos del Reglamento Argentino de Estructuras de Madera (INTI-CIRSOC 601) y por lo tanto tiene el aval normativo para la construcción de viviendas Estación Experimental Agropecuaria Bariloche Fil: Caballe, Gonzalo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Laboratorio de Ecología, Ecofisiología y Madera; Argentina Fil: Caballe, Gonzalo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: Diez, Juan Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Laboratorio de Ecología, Ecofisiología y Madera; Argentina Fil: Diez, Juan Pablo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: Martinez Meier, Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Laboratorio de Ecología, Ecofisiología y Madera; Argentina Fil: Martinez Meier, Alejandro. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentina Fil: Guillaumet, Alfredo Anibal. Universidad Tecnológica Nacional. Facultad Regional Venado Tuerto. Grupo de Investigación y Desarrollo de Estructuras Civiles; Argentina

Nothofagus pumilio forests in Tierra del Fuego are the southernmost forests in the world, where extreme climate conditions represent a challenge to attain sustainable forest management. Retention forestry was proposed as an alternative to increase the species conservation in managed stands. Here, we synthetized results related to the implementation of a variable retention harvesting based on a combination of aggregate patches and dispersed retention during the last 18 years comparing with other silviculture proposals (e.g., shelterwood cuts) and control treatments (primary unmanaged forests). We summarized the results for (i) sawmill operations, (ii) timber yield, (iii) overstory stability, (iv) forest structure, (v) microclimate and natural cycles, (vi) natural regeneration dynamics (flowering, seeding, foraging, recruitment, growth, and mortality), and (vii) biodiversity (mammals, understory plants, mistletoes, birds, arthropods, mosses, lichens, and fungi). In general, aggregate patches maintained forest structure and micro-environmental variables, and slightly increased biodiversity and forest reproduction variables compared to unmanaged primary forests. On the contrary, dispersed retention decreased forest structure variables and greatly increased biodiversity (richness and abundance) when it was compared to unmanaged primary forests. Ecological conditions are influenced by variable retention harvesting, but direction and magnitude of the effect depend and differ according to retention types. Besides this, biodiversity taxa greatly differed among groups depending on retention types. In general, the species assemblages in aggregate patches were similar to those found in primary unmanaged forests, while they were significantly modified in the dispersed retention. This occurred due to (i) local extinction of some original species, (ii) the introduction of native species from the surrounding environments, or (iii) the invasion of exotic species. This silvicultural method has been a useful tool to conserve biodiversity and ecosystem functions, approaching to the balance between economy, ecology, and social requirements in the managed areas., Facultad de Ciencias Agrarias y Forestales, Consejo Nacional de Investigaciones Científicas y Técnicas

En la selva, la dinámica de disturbios de origen natural o humano genera cambios en la cobertura arbórea y en la cantidad y la calidad de luz que llega al sotobosque. Los cambios debidos a los disturbios representan un continuo de condiciones microambientales que garantizan la coexistencia de las especies. El conocimiento de los requerimientos de las especies y la evaluación de los microambientes óptimos para su supervivencia y crecimiento permite planificar estrategias de manejo a fin de recuperar áreas forestales degradadas. Trabajamos en un bosque nativo ubicado en San Antonio, Misiones, con una especie nativa de alto valor ecológico y maderero: Cabralea canjerana (Vell.) Mart. (cancharana). El objetivo fue evaluar el establecimiento de esta especie bajo diferentes intensidades de cobertura de dosel del bosque. Se establecieron 2 ensayos: uno en macetas, en el que se evaluó la supervivencia y el crecimiento de plantas expuestas a dos condiciones de cobertura natural contrastantes, y otro con plantación a campo en un gradiente de cobertura generado por claros naturales. En ambos ensayos, más de 90% de las plantas de cancharana se establecieron inicialmente en un gradiente muy amplio de cobertura. En macetas, las plantas sin cobertura (sol pleno) fueron afectadas por heladas durante el invierno. A 4 años de realizada la plantación en los claros, la supervivencia fue de 70% y la mayor mortalidad se registró en microambientes con menor incidencia de luz. Concluimos que se puede enriquecer el bosque nativo con cancharana, que el microambiente no afecta la supervivencia durante el primer año, pero que el crecimiento posterior es mayor en posiciones con menor cobertura. La especie tolera cambios abruptos de cobertura, por lo que la limpieza del sotobosque y la apertura de claros benefician su crecimiento., The natural dynamic of the rainforest generates changes in the canopy coverage and, consequently, in the quality and quantity of light that reaches the understory. Similar effects can be achieved by the anthropogenic selective extraction of trees. The microsites produced by the disturbances represent a continuum of environmental conditions that ensures the coexistence of many species. The knowledge of the requirements of the species and the evaluation of the optimal microenvironments to plant growth are useful to build tools to restore degraded areas. We worked in a native rainforest in San Antonio, Misiones, Argentina, focused in a species that has high timber and ecological value: Cabralea canjerana (Vell.) Mart. (cancharana). The aim was to evaluate the establishment of cancharana under different coverage conditions. Two experiments were carried out: a pot experiment in which survivor and growth under two extreme natural coverage were evaluated, and a field experiment in which cancharana was planted in a gradient of coverage produced by natural gaps. In both experiments, more than 90% of the cancharana plants were initially established in a wide gradient of coverage. In the pot experiment, plants without forest coverage (full sun) were damaged by the frost in winter. Four years after the plantation, 70% of the plants survived in the field experiment and mortality was observed mostly in microenvironments with lower light incidence. We conclude that cancharana can establish and survive in many microenvironmental conditions within the rainforest, it acclimates in few months to sudden changes in coverage and, one year after planting, its growth arises with higher availability of light. The species tolerates sudden changes in coverage, therefore the remove of the understory or gap opening stimulate cancharana growth., Instituto de Fisiología Vegetal

En los últimos años Corymbia spp. y sus híbridos comenzaron a revalorarse como un género importante para la obtención de madera de calidad para usos sólidos de alto valor en diferentes regiones del mundo. Con el objetivo de evaluar el comportamiento de materiales cosechados en el área de distribución natural de Corymbia citriodora subsp. citriodora (CCC), Corymbia citriodora subsp. variegata (CCV) y Corymbia maculata (CM), al 9.º año de edad se evaluó el crecimiento en diámetro, altura, volumen y rectitud del fuste de 22 orígenes pertenecientes a dichas entidades en tres sitios de la Mesopotamia argentina. El análisis a nivel de sitios individuales mostró que CCV fue el taxón más promisorio. En dos de los sitios evaluados CCV superó en volumen y rectitud del fuste a las otras entidades y en el tercer sitio tuvo un crecimiento levemente inferior a CM, aunque sin diferencias estadísticas significativas. El análisis conjunto a nivel de orígenes dentro de taxones reveló baja interacción a través de los sitios ya que la correlación genética fue alta tanto para el volumen como para la rectitud del fuste (rgB= 0,77 y 0,99 respectivamente). Dada la existencia de muy buenos ejemplares dentro de los orígenes de CCV, se seleccionaron 30 ejemplares sobresalientes en volumen a través de los tres sitios. Estos individuos luego de movilizados y propagados vía injerto, conformarán el primer Huerto Semillero Clonal de CCV en Argentina. Se prevé que la ganancia genética de dicho huerto será aproximadamente del 17% en relación con el volumen promedio de todos los individuos evaluados de CCV. In recent years Corymbia spp. and their hybrids began to revalue as an important genus for the obtention of quality wood for solid high-value applications in different regions of the world. With the objective to evaluate the behavior of materials collected in the natural distribution area of Corymbia citriodora subsp. citriodora (CCC), Corymbia citriodora subsp. variegata (CCV) and Corymbia maculata (CM), the growth in volume (VOL) and the stem straightness (RF) were evaluated at 9th years of growth in 22 provenances belonging to these entities in three sites of the Mesopotamia region of Argentina. The site-site analysis showed that CCV was the most promising material. In two of the sites evaluated CCV overcame in VOL and RF to the other entities; at the third site had a slightly less growth than CM, although the statistical analysis did not reveal significant difference. The combined analysis revealed a low interaction among sites, since the genetic correlation at provenances within taxa level was high for stem volume and straightness (rgB = 0.77 and 0.99 respectively). Given the good performance of CCV and the existence of very good specimens within the provenances, we selected 30 outstanding individuals in volume across the three sites. These individuals, after being mobilized and propagated by grafting, will form the first Clonal Seed Orchard of CCV in Argentina. It is expected that the genetic gain of the Orchard for VOL in relation to the average of all the CCV assessed individuals is around 17%. EEA Bella Vista Fil: Lopez, Juan Adolfo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; Argentina Fil: Vera Bravo, Carlos David. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; Argentina

En el mundo hay alrededor de 400 especies de sauces, casi todos crecen en el hemisferio Norte. Salix Humboldtiana es la única especie que llega en su distribución natural hasta Sudamérica, extendiéndose desde México hasta Argentina y Chile, siendo su límite austral el Río Chubut. Estación Experimental Agropecuaria Bariloche Fil: Martinez, Abel Hector Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Agencia de Extension Rural Zapala; Argentina

The endangered Cedrela balansae C.DC. (Meliaceae) is a high-value timber species with great potential for forest plantations that inhabits the tropical forests in Northwestern Argentina. Research on this species is scarce because of the limited genetic and genomic information available. Here, we explored the transcriptome of C. balansae using 454 GS FLX Titanium next-generation sequencing (NGS) technology. Following de novo assembling, we identified 27,111 non-redundant unigenes longer than 200 bp, and considered these transcripts for further downstream analysis. The functional annotation was performed searching the 27,111 unigenes against the NR-Protein and the Interproscan databases. This analysis revealed 26,977 genes with homology in at least one of the Database analyzed. Furthermore, 7,774 unigenes in 142 different active biological pathways in C. balansae were identified with the KEGG database. Moreover, after in silico analyses, we detected 2,663 simple sequence repeats (SSRs) markers. A subset of 70 SSRs related to important “stress tolerance” traits based on functional annotation evidence, were selected for wet PCR-validation in C. balansae and other Cedrela species inhabiting in northwest and northeast of Argentina (C. fissilis, C. saltensis and C. angustifolia). Successful transferability was between 77% and 93% and thanks to this study, 32 polymorphic functional SSRs for all analyzed Cedrela species are now available. The gene catalog and molecular markers obtained here represent a starting point for further research, which will assist genetic breeding programs in the Cedrela genus and will contribute to identifying key populations for its preservation. Fil: Torales, Susana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; Argentina Fil: Rivarola, Maximo Lisandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Gonzalez, Sergio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Inza, María Virginia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; Argentina Fil: Pomponio, María Florencia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; Argentina Fil: Fernández, Paula. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Acuña, Cintia Vanesa. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Zelener, Noga. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; Argentina Fil: Fornes, Luis Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero; Argentina Fil: Hopp, Horacio Esteban. Universidad de Belgrano. Facultad de Ciencias Exactas y Naturales; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina Fil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Marcucci Poltri, Susana Noemí. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina

Los bosques en Lagunas de Epulauquen (36º49’S; 71º04’O) han sido considerados como la población más septentrional de Nothofagus obliqua en Argentina. En años recientes se ha cuestionado su verdadero estatus. La convergencia de rutas migratorias y la hibridación histórica con Nothofagus alpina fueron las hipótesis planteadas como posible origen de esta distinción. Lagunas de Epulauquen forests (36°49'S; 71°04'W) have been considered the northernmost population of Nothofagus obliqua in Argentina. Recently, however, its taxonomic status has been questioned due to its morphological, architectural and genetic distinctiveness. The convergence of migratory routes and hybridization with Nothofagus alpina are the two main hypotheses proposed to explain the distinctiveness of this population. Despite its unique characteristics, no evaluation of its putative origin has been carried out. In order to test the hypothesis of hybridization we analyzed nuclear Adh and ITS fragment sequences together with 12 nuclear microsatellites. These nuclear regions were selected based on their previously reported divergence between N. obliqua and N. alpina. The survey was conducted in 12 individuals from Lagunas de Epulauquen, and individuals from N. obliqua (8), N. alpina (1), N. macrocarpa (2), N. glauca (4) and N. leonii (2). By combining a phylogenetic analysis with a principal coordinate analysis of microsatellite data, we showed that Lagunas de Epulauquen individuals were closely related to other N. obliqua individuals, while hybridization with N. alpina was not detected. Our results indicate that hybridization processes could be discarded as the origin of the Lagunas de Epulauquen distinctiveness. The hypothesis of the convergence of two N. obliqua migratory routes at this latitude was reinforced based on detected patterns of genetic diversity. Notwithstanding, its high geographical isolation seems to be also a key evolutionary factor to explain the distinctiveness of this population. Lagunas de Epulauquen population could be therefore included within Argentinean N. obliqua domestication and conservation programs. EEA Bariloche Fil: Azpilicueta, Maria Marta. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina Fil: El Mujtar, Veronica Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina Fil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina

info:eu-repo/semantics/publishedVersion

Premise of the study: We present a set of 23 polymorphic nuclear microsatellite loci, 18 of which are identified for the first time within the riparian species Salix humboldtiana (Salicaceae) using next‐generation sequencing. Methods and Results: To characterize the 23 loci, up to 60 individuals were sampled and genotyped at each locus. The number of alleles ranged from two to eight, with an average of 4.43 alleles per locus. The effective number of alleles ranged from 1.15 to 3.09 per locus, and allelic richness ranged from 2.00 to 7.73 alleles per locus. Conclusions: The new marker set will be used for future studies of genetic diversity and differentiation as well as for unraveling spatial genetic structures in S. humboldtiana populations in northern Patagonia, Argentina. EEA Bariloche Fil: Bozzi, Jorge Alfredo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina Fil: Liepelt, Sascha. University of Marburg. Faculty of Biology. Conservation Biology Group; Alemania Fil: Ohneiser, Sebastian. University of Marburg. Faculty of Biology. Conservation Biology Group; Alemania Fil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina Fil: Marchelli, Paula. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Leyer, Ilona. University of Marburg. Faculty of Biology. Conservation Biology Group; Alemania. University of Geisenheim. Institute of Botany, Plant Ecology and Nature Conservation; Alemania Fil: Ziegenhagen, Birgit. University of Marburg. Faculty of Biology. Conservation Biology Group; Alemania Fil: Mengel, Christina. University of Marburg. Faculty of Biology. Conservation Biology Group; Alemania

Reforestation measures for degraded lands, strategies for the sustainable management of forest resources, and agroforestry practices that incorporate trees into farming systems are increasingly demonstrating their promise for producing commercialized tree products. Although the level of investment so far has remained modest, the challenge is to find ways to scale up promising investments in a way that will have a clear impact at the landscape level. These types of investments can help achieve the triple wins of climate-smart agriculture: increased incomes and yields, climate change adaptation and greenhouse gas mitigation.Market trends are promising for a wide range of tree-based technologies, including tropical fruits, cashews, honey, timber and wood products, lipids, gums and resins, tree crops, and agroforestry systems. In many cases, African entrepreneurs, farmers, civil society, and governments have responded dynamically to the widespread challenge of land degradation. The continent is dotted with landscapes where production of trees on farms and in managed forests has grown dramatically to meet market and subsistence needs; sustainable agricultural practices and revegetation have restored soils and watersheds; and key conservation areas are being protected. However, this is not happening at the scale required by societal needs in Africa. In part, this is due to a lack of strategic cooperation and coordination between private sector investors and land managers (who are focused on realizing profitable opportunities and meeting their own needs) and public and civil society actors (who are focused on restoring forest cover and ecosystem services). Such coordination is only possible when the biophysical potential for landscape restoration, private sector investment opportunity and incentives, and societal demand for multiple benefits converge. Much can be learned from examples of large-scale landscape restoration in Ethiopia, Kenya, Niger, Tanzania, and Zambia, and the variable roles of the private sector, farmers, government, and civil society in supporting and undertaking investment.

Seed production in tropical timber trees is limited by abiotic resources, pollination and pre-dispersal seed predation. Resource availability is influenced by the number of competing trees and by lianas that often reach high densities in disturbed parts of tropical forests. The distance between conspecific trees affects pollination efficiency and seed predation intensity, and may therefore indirectly affect the long-term sustainability of selective logging. Here we investigate how reproductive status and the number of seeds dispersed per tree are affected by liana load, distance to the nearest conspecifics, number of competing neighbours and tree diameter in the timber trees Cariniana ianeirensis and Terminalia oblonga. The study is based on a large-scale silvicultural experiment in lowland Bolivia. We found that the reproductive status of the two species was negatively correlated with liana cover and positively with tree diameter. In C. ianeirensis the most liana-infested trees dispersed fewer seeds. In T. oblonga the intensity of pre-dispersal seed predation decreased with distance to the nearest conspecifics. There was no evidence that seed viability or seed production decreased with distance to nearest conspecifics in either species as would be expected if isolation resulted in increased self-pollination. Our results indicate that reproduction can be severely reduced in timber trees if the largest, most healthy and least liana-covered trees are logged, but that liana cutting on the remaining seed trees can considerably improve seed production. In some species seed production may be further improved by ensuring that seed trees are located far apart.

Sustainable management of selectively logged tropical forests requires that felled trees are replaced through increased recruitment and growth. This study compares road track and roadside regeneration with regeneration in unlogged and selectively logged humid tropical forest in north-eastern Bolivia. Some species benefited from increased light intensities on abandoned logging roads. Others benefited from low densities of competing vegetation on roads with compacted soils. This was the case for the small-seeded species Ficus boliviana C.C. Berg and Terminalia oblonga (Ruiz & Pav.) Steud. Some species, e.g. Hura crepitans L., displayed patchy regeneration coinciding with the presence of adult trees. Our results suggest that current management practices could be improved by intensifying logging in some areas to improve regeneration of light demanding species. Sufficient seed input in logged areas should be ensured by interspersing large patches of unlogged forest with logged areas. This may also assist regeneration of species that perform poorly in disturbed areas.

This paper has been presented by membres of the SRAP project team (Smallholder Rubber Agroforestry Project) from ICRAF and CIRAD-ES; Smallholder rubber plantations in Indonesia, representing more than 80% of the total rubber areas, are very unique in the world. Most smallholder rubber areas are multi-strata in nature. Rubber is not the only perennial crop in that area, but also mixed with timber trees (forest re-growth), fruit trees, and different annual crops. Scientists identified these multistrata systems or called “Jungle Rubber” have multiple functions such as main income source for many farmers; keeping certain level of the forest biodiversity; Carbon sequestration; soil and water conservation. Many efforts have been done by the Indonesian Government to improve the productivity of jungle rubber through monocuture system such as Nucleolus Estate for Smallholding (NES); Project Management Unit (PMU); and Partial System. However, the rate of rubber replanting through those specific projects are too small compared to the total rubber areas in Indonesia. Taking into account the positive aspects of the Rubber Based Agroforestry Systems (RAS), ICRAF, CIRAD and IRRI worked jointly to implement various RAS systems in order to provide farmers better technological options for managing their farms. Results presented in this paper are collected from both on-station and on-farm research. At on-station, rubber planted at a double rows spacing (6m x 2m x 14m) with and without perennial intercrops was monitored and compared to that of the normal spacing (6mx3m). Rubber girth with double row spacing reached tappable size at five years after planting and similar to that planted with normal spacing. Rubber growth at the plot planted with Acacia mangium a very fast growing tree, at the same time with rubber, was very slow: a haft of that of the other treatments. If the fast growing trees are planted two years after rubber planting, then rubber growth is similar to that of normal spacing. Three types of RAS were tested at farmers' plots (RAS1, RAS2, and RAS3). The total number of participants is about 150 farmers, in 100 ha plots, distributed in Jambi, West Kalimantan, West Sumatra and South Sumatra. Results of clone comparison in RAS 1 type of trial (maintenance only on rubber rows) showed that rubber growth variability was more due to the variability of farmers' plots and frequencies of weeding. Rubber clones such as PB 260; RRIC 100 and BPM1 planted under RAS 1 can adapt the RAS conditions and can be tapped at 5-7 years after planting. These findings provide farmers alternatives to develop more environmentally friendly and divers systems in their farms, compared to that of monoculture system. This paper presents also various results related to more intensive RAS (RAS1 and RAS 3).

Terminalia oblonga (Ruiz et Pav.) Steud. is a common timber tree in lowland Latin America which is widely utilized and economically and ecologically valuable. The species suffers from reduced natural recruitment but the control of regeneration by environmental factors is incompletely understood. In the forest management plots of the BOLFOR project (La Chonta, Bolivia) we investigated the effects of soil disturbance, litter layer and canopy openness on seedling emergence and survival. Soil disturbance and a thin litter layer favoured seedling emergence, disturbance had also a positive effect on seedling survival, whereas canopy openness had no significant effect on emergence but influenced survival positively. The results are discussed with respect to the life history traits of T. oblonga and forest regeneration, which need to be considered for implementation of sustainable logging strategies and forest conservation. It is concluded that the regeneration of T. oblonga is favoured by moderate logging although the long-term effects need further research.

Tesis (Maestría) -- CATIE, Turrialba (Costa Rica), 2002 62 páginas 13 ilus. 20 tab. Referencias 51-57 Se estudió la contribución de cinco especies de árboles de sombra sobre la disponibilidad y dinámica de nitrógeno en tres sistemas agroforestales con café. La evaluación se llevó a cabo al final de la estación seca en marzo del 2002 en la zona sur de Costa Rica. Las fincas privadas fueron seleccionadas con Coffea arabica L. Cultivar Costa Rica 95 de 4 años en Verde Vigor, Caturra de 14 años en Santa Fe y Catuaí rojo y amarillo (en mezcla) de 6 años en San Pedro. Las especies de sombra estudiadas fueron: las leguminosas Inga sp, Erythrina poeppigiana, Walp. (O.F.Cook) así como las maderables Eucalyptus deglupta Blume., Terminalia ivorensis A. Chev. y Terminalia amazonia. El estudio también incluye el sistema de café a pleno sol. The contribution of five shade tree species on Nitrogen availability and dynamics was studied in coffee (Coffea arabica L.) agroforestry systeMON during the end of the 2002 dry season (March) on private farMON in the south of Costa Rica: 7-yr-old var. Costa Rica 95 (Verde Vigor farm), 14-yr-old var. Caturra (Santa Fe farm) and a mix of vars. red and yellow Catuaí (San Pedro farm). Treatments consisted of coffee under (leguminous) service tree shade (Inga sp. or Erythrina poeppigiana Walp. (O.F. Cook), under timber tree shade (Eucalyptus deglupta Blume., Terminalia ivorensis A. Chev. or T. Amazonia) or in full sun.

Tesis (M. Sc) -- CATIE, Turrialba (Costa Rica), 2000 73 páginas 11 fig. 9 tab. Referencias 59-62 Se estudió el efecto Eucalyptus deglupta o Terminalia ivorensis sobre plantas de café (Coffea arabica var. Costa Rica) establecidas a diferentes distancias de los árboles, se analizó el efecto de los maderables sobre la arquitectura, crecimiento y desarrollo del café. Se desarrollaron modelos para predecir el número de frutos por planta asociadas con E. deglupta o T. ivorensis. Se comparó la eficiencia del muestreo irrestricto aleatorio, el muestreo sistemático y el muestreo por conglomerados para evaluar los asocios café-maderables y se estimó el tiempo que demandaron las observaciones de campo para las variables medidas en las plantas de café. El estudio se desarrolló en un experimento establecido en la finca "Verde Vigor", Pérez Zeledón, Costa Rica en suelos clasificados como Ustoxic Palehumult con pH 4.6-5.2, localizada a 700 MONnm, con una precipitación anual de 3.853 mm. Los resultados obtenidos en este estudio, sugieren que el uso de T. ivorensis en sistemas agroforestales con café, requiere de podas más drásticas de sus ramas después del primer año de establecimiento y probablemente raleos más tempranos que E. deglupta. Es necesario considerar si en los sistemas agroforestales café-maderables, conviene plantar café a menos de un metro de distancia de los árboles. La altura de plantas, el número de nudos en el tallo principal y el número de ramas primarias por planta, fueron buenos indicadores para detectar el efecto de especies maderables sobre las plantas de café establecidas a diferente distancia de los árboles. Al nivel de estratos, la observación del área foliar para el estrato inferior, los nudos productivos y el número de frutos por rama después del nudo ocho, fueron buenos indicadores para conocer como pueden afectar los árboles maderables el desarrollo del café. The effect of Eucalyptus deglupta or Terminalia ivorensis on coffee (Coffea arabica var. Costa Rica) plants, established at different distances from the trees, was evaluated. In particular, the effect of these timber trees on the architecture, growth and development of coffee was analyzed. Models were developed to predict the number of fruits per plant associated with E. deglupta or T. ivorensis. The efficiency of complete random sampling, systematic sampling and sampling by conglomerates to evaluate the coffee was compared. Additionally the time required for the field observations of the different coffee variables was measured. The study was carried out in an experiment established in the "Verde Vigor" farm, Pérez Zeledón, Costa Rica, in soils classified as Ustoxic Palehumult, with pH of 4.6 - 5.2, located at 700 m.a.s.l., with an annual precipitation of 3853 mm. The results obtained in this study suggest that if T. ivorensis is used as a coffee shade tree, more severe pruning of the branches after the first year of establishment and probably earlier thinning than for E. deglupta is required. It is necessary to consider if, in the coffee-timber tree agroforestry system, it is convenient to plant coffee at least at one meter from the tree. Plant height, number of nodes on the main stem, and the number of primary branches per plant, were good indicators to detect the effect of timber tree species on coffee plants established at different distances from the trees. At the level of the strata, the observation of leaf area for the lower strata, the productive nodes and the number of fruits per branch below stem node eight were good indicators of the effect of the timber trees on the development of coffee plants.

Tesis (Mag.Sc.) - CATIE, Turrialba (Costa Rica), 2000 El objetivo del estudio fue de conocer el rol de los sistemas agroforestales (SAF) cacaoteros y bananeros en la conservación de la biodiversidad en la zona indígena de Talamanca, Costa Rica. Se caracterizó la diversidad y densidad de árboles de sombra presentes en bosques, cacaotales y bananales, a través de parcelas temporales (20 X 50 m). Se comparó la diversidad y abundancia relativa de mamíferos terrestres en los tres hábitats a través del registro de sus huellas en transectos. Adicionalmente se realizaron entrevistas semiestructuradas a 20 productores cacaoteros y 20 bananeros para determinar los beneficios y problemas que la biodiversidad representa para los productores. The objective of the study was to determine the role of cacao and banana agroforestry systeMON in the conservation of biodiversity in the indigenous region of Talamanca, Costa Rica. The diversity and density of trees in forests, cacao plantations and banana plantations was characterized using temporary plots (20 X 50 m). The diversity and relative abundance of terrestrial mammals in the three habitats was compared by registering mammal footprints in established transects. In addition, interviews were conducted with 20 cacao farmers and 20 banana farmers to determine both the benefits and probleMON of the biodiversity present in their agroforestry systeMON.

45 páginas Documento en inglés con textos en alemán Agroforestry is recognized as one of the major objectives In CATIE's new planning and organlzational structure. The Project's general objective (development and dissemination of agroforestry production systems for small farmers in the Central American Isthmus) is in complete accordance with the strategic plan of its main counterpart organization. Collection, evaluation and documentation of bio-physical, socio-cultural and economic data of about 60 on-farm experiments in four project locations of Costa Rica and Panama are going on. Progress results demonstrate that the objectives can be reached. Needs and opportunities of the target group's individuals had been discussed initially with selected farmers; nine research topics were chosen for on-farm trials (including timber trees and leguminous trees in cocoa plantations, trees as living supports for black pepper, timber trees in farm boundaries, forestry plantations using modified Taungya). In Puriscal (Costa Rica) component. Extension work at both the community and the farmers level is aimed at providing a basis for future development of models for extension by local and/or national organizations. First measures have been taken to transfer the Project's methods of technology generation, validation and dissemination to three other countries of Central America.

En esta investigación se estudia el Crecimiento de regeneraciones naturales coetáneas de cedro y de roble (Tabebuia rosea) en la región de Urabá, Antioquia, empleando el método de los tiempos de paso. Para el estudio del cedro se establecieron 17 parcelas permanentes, las primeras de las cuales se midieron en mayo de 1977 y por última vez en junio de 1984. Para las primeras etapa del crecimiento se midieron dos parcelas jóvenes de edad conocida. El total de árboles que aportaron información para el estudio del cedro fue de 290. En el caso del roble se establecieron en junio de 1980 diez parcelas permanentes las cuales se remidieron en junio de 1982. Se utilizo además información de tres parcelas de edad conocida para el crecimiento inicial. En total se alcanzaron a medir en las dos fechas 638 árboles. Con base en la infomacion suministrada por tales mediciones se dibujaron gráficas del diámetro en función de la edad para 120%, 40%, 60%, 80% y 100% de los arboles en orden de los de mayor crecimiento hasta el total para ambas especies. Tal procedimiento posibilitó la simulación del desarrollo de plantaciones con entresacas por lo bajo y de sus efectos en el diámetro, área basal y volumen. Como consecuencia de todo el procedimiento se elaboraron tablas de rendimiento para ambas especies.

Tesis (Mag.Sc) -- CATIE, Turrialba (Costa Rica) -- UCR, San José (Costa Rica), 1984 El presente estudio tiene como objetivo evaluar el efecto de dos especies arbóreas funcionalmente diferentes, sobre los factores de producción de una pastura de Cynodon nlemfuensis y su rendimiento. La pastura de Estrella estuvo asociada con árboles maderables de Cordia alliodora, asociada con árboles leguminosos de Erythrina poeppigiana y sin árboles. El estudio comprendió la medición de la producción de biomasa (MS), proteína cruda (PC) y la digestibilidad in vitro (porcentaje DIVMS) de la pastura, separada en los componentes gramíneas y plantas herbáceas de hoja ancha. La producción de biomasa fue mayor en las pasturas con Erythrina. El contenido de PC y la DIVMS fueron iguales para las tres pasturas