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Populus deltoides 'Australiano 129/60': variación axial de la densidad y desarrollo de un modelo predictivo de la densidad del árbol completo Populus deltoides clone 'Australian 129-60': density axial variation and predictive model for whole tree density  [cached]
Gastón Diaz,Silvia Monteoliva,Javier álvarez,Ezequiel Fernández Tschieder
Bosque (Valdivia) , 2010,
Abstract: Los objetivos de este trabajo fueron determinar la variación axial de la densidad de la madera de Populus deltoides ‘Australiano 129/60’ y desarrollar un modelo predictivo de la densidad total del árbol a partir de la densidad a una única altura. Se voltearon 11 árboles de 10 a os de tres clases diamétricas en Buenos Aires, Argentina. Se extrajeron muestras a siete alturas del fuste (0,5 m; 0,7 m; 1,0 m; 2,2 m; 6,6 m; 11,0 m y 15,4 m). Se determinó la densidad normal media y media ponderada por volumen al 15% de contenido de humedad. Se realizaron ANOVAs entre alturas de muestreo y clases diamétricas. Se realizaron regresiones lineales y no lineales, simples y múltiples, para ajustar modelos de predicción de la densidad media ponderada del fuste, tomando como variables predictoras la densidad normal a 1 m de altura y el diámetro a la altura del pecho. La densidad media fue de 458 ± 35 kg m-3 y la densidad ponderada de 470 ± 14 kg m-3. La variación axial mostró un aumento significativo de los valores de densidad desde la base hacia el ápice. La densidad tomada a 1,0 m subestimó la densidad ponderada del árbol completo en un 11%. Se verificó una mayor densidad en las clases diamétricas superiores. Se considera factible producir estos álamos con mayores diámetros y obtener al mismo tiempo mayor densidad. Es posible ajustar modelos de estimación de la densidad media ponderada a partir de una muestra tomada a una única altura y el DAP. The aims were to determine the axial variation pattern for wood density of Populus deltoides clone ‘Australian 129-60’ and to develop a predictive model for whole tree density from density at one sample height. Eleven ten-year-old trees from three diametric classes were sampled in Buenos Aires Province, Argentine. Disks were taken at seven sampling heights (0.5 m; 0.7 m; 1.0 m; 2.2 m; 6.6 m; 11.0 m and 15.4 m). Density and weighted density were determined at 15% of moisture content. An analysis of variance was carried out for sampling heights and diametric classes. The relationship between whole tree density and predictive parameters, density at 1.0 m height and Diameter at breast height (DBH), was quantified using linear and non linear regression analyses. Clone mean density was 458 ± 35 kg m-3 and weighted density was 470 ± 14 kg m-3. Density axial variation shows significantly increasing values from the lower sampling height to the top. Density taken at breast height, approximately (1.0 m), underestimates (11%) the weighted density of whole tree. It is feasible to produce high diameters poplars and to obtain major wood dens
Susceptibilidad de híbridos de Populus spp. al ataque de áfidos y roya en tres localidades de Chile Susceptibility of Populus spp. hybrids to aphids and rusts at three localities of Chile  [cached]
María E Rubio-Meléndez,Francisco Zamudio,Claudio C Ramírez
Bosque (Valdivia) , 2011,
Abstract: En los últimos a os se ha generado un creciente interés en el potencial forestal de las especies e híbridos del género Populus (álamos) en Chile. Sin embargo, algunas plagas y patógenos atacan severamente a estas plantaciones. Con el fin de identificar algunos híbridos resistentes (o menos susceptibles) a estas plagas, se evaluó la susceptibilidad de algunos taxones de Populus spp. al ataque del áfido Chaitophorus leucomelas y al hongo Melampsora spp. El estudio se realizó en tres localidades del centro-sur de Chile. Los resultados revelan que la densidad de áfidos fue mayor en marzo, particularmente en Coinco (región de O’Higgins) y menor en Pillanlelbún (región de Los Ríos) y Yumbel (región del Biobío). En Pillanlelbún el taxón más susceptibles a áfidos correspondió a TD×TD [ (P. trichocarpa x P. deltoides) x (P. trichocarpa x P. deltoides)] y los menos susceptibles fueron TD×D [ (P. trichocarpa x P. deltoides) x P. deltoides], T×N (P. trichocarpa x P. nigra), TMxTM [(P. trichocarpa x P. maximowitzii) x (P. trichocarpa x P. maximowitzii)] y TD×T [ (P. trichocarpa x P. deltoides) x P. trichocarpa]. Las infecciones con Melampsora spp. se presentaron en orden decreciente en Coinco, Yumbel y Pillanlelbún. El taxón T×N fue el más susceptible a roya en las tres regiones, mientras que los menos susceptibles fueron TD×T, TD×D y TD×T. Estas susceptibilidades variaron entre localidades, principalmente para áfidos. No hubo correlación entre la abundancia de C. leucomelas y de Melampsora spp. Se discuten los factores genéticos y ambientales que podrían explicar estos resultados. In the last few years an increasing interest on species and hybrids of the genus Populus has occurred in Chile. However, such plantations are strongly affected by pest and diseases. With the aim to identify potentially resistant (or less susceptible) hybrids of the genus Populus, the susceptibility of some poplar hybrids growing in experimental nurseries in Southern-Center Chile to the aphid Chaitophorus leucomelas Koch and to the rust Melampsora spp. was assessed. Results showed that aphid abundance was higher in the month of March, particularly in Coinco (O’Higgins Region) and lower in Pillanlelbún (Los Ríos Regions) and Yumbel (Biobío Region). In Pillanlelbún the most susceptible hybrid to aphids was TD×TD [ (P. trichocarpa x P. deltoides) x (P. trichocarpa x P. deltoides)], and the less susceptible ones were TD×D [ (P. trichocarpa x P. deltoides) x P. deltoides], T×N (P. trichocarpa x P. nigra), TMxTM [(P. trichocarpa x P. maximowitzii) x (P. trichocarpa x P. maximowitzii)] and TDxT [
Susceptibilidad clonal del álamo (Populus sp.) al ataque de Platypus mutatus en Buenos Aires, Argentina Cloning susceptibility of Poplar (Populus sp.) when attacked by Platypus mutatus in Buenos Aires, Argentina  [cached]
Jorge Luis Marquina,Raúl Marlats,Marcela Nú?ez Cresto
Bosque (Valdivia) , 2006,
Abstract: El objetivo del trabajo fue caracterizar la incidencia de Platypus mutatus en varios clones de Populus de uso comercial, en plantaciones ubicadas en Palantelén, Alberti, Buenos Aires, Argentina (35° 40’ S, 60° 15’ O). Sobre rodales de 10 a os de edad de Populus deltoides cvs. Catfish 2, Stoneville 62, Stoneville 66, Stoneville 71, y Populus x euroamericana cvs. I-214 y Conti 12, se comparó el número medio de galerías por ejemplar, y se evaluaron quebraduras ocasionadas por la plaga y supervivencia de ejemplares quebrados. El ordenamiento de clones resultó variable según la perturbación analizada. Conti 12 y Stoneville 66 fueron los clones más afectados medidos por la presencia de galerías; I-214, Stoneville 71 y Stoneville 62, fueron los menos afectados. Catfish 2 y Stoneville 66, seguidos por Conti, se presentaron como más propensos al quiebre; I-214 no presentó quebraduras. Conti 12 fue el de menor supervivencia; Stoneville 71 no registró muertes, a pesar de las quebraduras; Stoneville 62, Stoneville 66, y Catfish 2, presentaron alta supervivencia de ejemplares quebrados. The objective of the present work was to characterize the incidence of Platypus mutatus on clones of poplars from plantations located at Palantelén, Alberti, Buenos Aires, Argentina (35° 40’ S; 60° 15’ W). 10-year-old plantations of Populus deltoides cvs. Catfish 2, Stoneville 62, Stoneville 66, Stoneville 71 and Populus x euroamericana cvs. I-214 and Conti 12 were studied. The number of galleries by trunk, breaks caused by the insect and survival of broken trees were analyzed. Classifications of clones depending on the pest varied according to the analyzed perturbation. Conti 12 and Stoneville 66 were the most attacked clones measured by presence of galleries. I-214, Stoneville 71 and Stoneville 62 were the least attacked clones. Catfish 2 and Stoneville 66 were more easily broken; followed by Conti 12. I-214 did not have any broken plant. Conti 12 was the clone presenting the least survival of broken plants. Broken plants of Stoneville 71 did not die. Stoneville 62, Stoneville 66, and Catfish 2, presented high survival of broken trees.
Transición de madera juvenil a madura en un clon de Populus deltoides implantado en Buenos Aires Argentina Juvenile to mature wood transition in one clone of Populus deltoides implanted in Buenos Aires, Argentine  [cached]
Ana C Cobas,María C Area,Silvia Monteoliva
MADERAS : Ciencia y Tecnología , 2013,
Abstract: El objetivo del trabajo fue determinar la edad de transición de madera juvenil a madura a partir de las propiedades de la madera en un clon de álamo. Se muestrearon cinco árboles de 17 a os de Populus deltoides "Australia 129/60" de una plantación comercial. Se tomaron muestras a cinco alturas en el fuste: 0,3 m, 1,3 m, 4,2 m, 8,1 m y 15,9 m y se determinó anualmente: crecimiento, densidad de la madera, morfometría de fibras y vasos y área de pared. La edad de transición de madera juvenil a madura se determinó por el método de regresión segmentada. Los patrones de variación radial y axial de las diferentes propiedades fueron de un aumento de sus magnitudes con la edad y altura en el fuste. La edad de transición entre madera juvenil y madera madura no fue idéntica para todas las propiedades, definiéndose edades de transición de 4, 5, 7 y 9 a os dependiendo de la variable. La secuencia de maduración fue: área de pared, diámetro y frecuencia de vasos, ancho y longitud de fibras, densidad y espesor de pared. Las propiedades de la madera juvenil fueron inferiores con respecto a la madura, siendo el volumen del cilindro juvenil del 52%. The aim of this work was to determine the age at which the transition of the juvenile wood to the mature wood takes place, by means of the parameters: density, morphometry of fibers, and vessels in one poplar clone. Five 17-year-old Populus deltoides "Australia 129-60" trees were sampled from a commercial plantation in Buenos Aires, Argentina. Samples were taken at 5 heights from the trunk: 0.3 m, 1.3 m, 4.2 m, 8.1 m and 15.9 m and the annual radial growth, wood density, morphometry of fibers and vessels, and cell wall area were measured. Segmented regression analyses were used to determine the age of transition from juvenile to mature wood. The radial variation of different anatomical properties increased with age. The estimated age of transition from juvenile wood and mature wood was not identical for all properties. The transition ages were 4, 5, 7 and 9 years depending on the variable. The sequence of maturation was: cell wall area, vessel diameter and frequency, fiber width and length, density and wall thickness. Juvenile wood properties were significantly lower with respect to the mature wood. The volume of the juvenile wood was 52%.
Populus deltoides 'Australiano 129/60': variación axial de la densidad y desarrollo de un modelo predictivo de la densidad del árbol completo
Diaz,Gastón; Monteoliva,Silvia; álvarez,Javier; Fernández Tschieder,Ezequiel;
Bosque (Valdivia) , 2010, DOI: 10.4067/S0717-92002010000100008
Abstract: the aims were to determine the axial variation pattern for wood density of populus deltoides clone ?australian 129-60? and to develop a predictive model for whole tree density from density at one sample height. eleven ten-year-old trees from three diametric classes were sampled in buenos aires province, argentine. disks were taken at seven sampling heights (0.5 m; 0.7 m; 1.0 m; 2.2 m; 6.6 m; 11.0 m and 15.4 m). density and weighted density were determined at 15% of moisture content. an analysis of variance was carried out for sampling heights and diametric classes. the relationship between whole tree density and predictive parameters, density at 1.0 m height and diameter at breast height (dbh), was quantified using linear and non linear regression analyses. clone mean density was 458 ± 35 kg m-3 and weighted density was 470 ± 14 kg m-3. density axial variation shows significantly increasing values from the lower sampling height to the top. density taken at breast height, approximately (1.0 m), underestimates (11%) the weighted density of whole tree. it is feasible to produce high diameters poplars and to obtain major wood density at the same time. it is possible to fit models to estimate the mean weighted density of whole tree based on density at breast height approximately, with linear regression analysis.
Volume equation for Populus deltoides plantation in western Terai of Nepal  [PDF]
SK Gautam,HB Thapa
Banko Janakari , 2007, DOI: 10.3126/banko.v17i2.2158
Abstract: Allometric equations for estimating timber volume of Populus deltoides in plantation trial of Populus deltoides were developed. Direct measurement of 60 trees in western Nepal was done for this purpose. Six models were tested with simple linear regression analysis technique. The best fit equation for volume was quadratic (0.1500 - 0.0205DBH + 0.00105*DBH2) with diameter at breast height as an independent variable. Model recommended for estimating volume is based on diameter at breast height, because of the simplicity, easy to measure accurately in the field and the most common variable recorded in forest inventories. This model gave highest degree of determination (R2=0.88), and lowest standard error among the tested models.
Biodegradation of naphthalene and anthracene by chemo-tactically active rhizobacteria of populus deltoides
Bisht, Sandeep;Pandey, Piyush;Sood, Anchal;Sharma, Shivesh;Bisht, N. S.;
Brazilian Journal of Microbiology , 2010, DOI: 10.1590/S1517-83822010000400011
Abstract: several naphthalene and anthracene degrading bacteria were isolated from rhizosphere of populus deltoides, which were growing in non-contaminated soil. among these, four isolates, i.e. kurthia sp., micrococcus varians, deinococcus radiodurans and bacillus circulans utilized chrysene, benzene, toluene and xylene, in addition to anthracene and naphthalene. kurthia sp and b. circulans showed positive chemotactic response for naphthalene and anthracene. the mean growth rate constant (k) of isolates were found to increase with successive increase in substrate concentration (0.5 to 1.0 mg/50ml). b. circulans sba12 and kurthia sba4 degraded 87.5% and 86.6% of anthracene while, kurthia sp. sba4, b. circulans sba12, and m. varians sba8 degraded 85.3 %, 95.8 % and 86.8 % of naphthalene respectively after 6 days of incubation as determined by hplc analysis.
Alcanos lineales de la cera cuticular de hojas de Populus alba, Populus deltoides (Salicaceae), Robinia pseudoacacia(Fabaceae), Ulmus pumila(Ulmaceae) y Fraxinus Americana (Oleaceae) en Tandil, Buenos Aires, Argentina  [cached]
María L. Bakker,Patricia I. Alvarado
Darwiniana , 2006,
Abstract: Se coleccionaron hojas maduras de ejemplares adultos de Populus alba, Populus deltoides, Robinia pseudoacacia, Ulmus pumila y Fraxinus americana del Campus Universitario, Tandil, Buenos Aires, Argentina (37° 19 S, 59° 08 O) en febrero de 2004. La cera cuticular fue extraída, purificada, y el contenido y proporción relativa de n-alcanos de número impar de carbonos (C23 C35) fue cuantificado mediante cromatografía gas-líquido capilar. La concentración total de n-alcanos (mg/kg MS) fue P. alba (6935) > Robinia (1571) > P. deltoides (1379) > Ulmus (880) > Fraxinus (467). Los n-alcanos más abundantes en todas las especies fueron C27 y C29 que constituyeron entre 10 y 51% y entre 35 y 76% del total respectivamente, excepto en Fraxinus donde los más abundantes fueron C29 y C31 que constituyeron el 31 y 49% del total respectivamente. P. alba y P. deltoides difirieron no solo en la concentración total de n-alcanos sino también en la proporción relativa de C27 y C29, siendo C29 el n-alcano más abundante en la segunda especie (76%) igual que en Robinia (75%). La presencia de nalcanos de número par de carbonos no fue detectable o resultó muy baja en general en todas las especies, con excepción de C26, C28 y C30, este último se destacó particularmente en Fraxinus.
Cloning and expression analysis of an E-class MADS-box gene from Populus deltoides
B Zhang, X Zhang, H Li, X Zhou, X Su
African Journal of Biotechnology , 2009,
Abstract: An E-class MADS-box gene, PdMADS2, was isolated from Populus deltoides Bartr. ex Marsh male floral buds by RT-PCR. As shown by relative–quantitative real-time polymerase chain reaction analysis, the expression of PdMADS2 was high in apical and floral buds, intermediate in immature xylem and roots and low in mature leaves of adult male P. deltoides. In developing male floral buds, PdMADS2 expression was high and remained constant from July to September, increased significantly on February 6 and quickly fell to a very low level with the maturation of the flowers. In male inflorescences, PdMADS2 expression was abundant in the perianth cups and inflorescence peduncles; it was not detected in mature pollen. In female inflorescences, PdMADS2 was highly expressed in both ovaries and inflorescence peduncles. Our results suggest that PdMADS2 plays an important role in the development of inflorescence meristems and flower organs in poplar.
Variations in wood tratis in micro and macro propagated plantation woods of Populus deltoides Bartr. ex Marsh  [PDF]
Pramod K. Pande, Ramesh C. Dhiman
Advances in Bioscience and Biotechnology (ABB) , 2010, DOI: 10.4236/abb.2010.14035
Abstract: The paper presents a comparison between intra-ramet, intra-clonal and inter-clonal variations in girth at breast height (gbh), fiber length, fiber diameter, wall thickness, vessel element length, vessel element diameter and specific gravity in the ramets of L34, G3 and S7C15 clones of Populus deltoides at the age of 6 years old produced from planting material grown by macro- and micro-propagation techniques. Variance ratio (F) test indicated that intra-ramet variations were non-significant for all the characters except specific gravity for height in L34 for macro and specific gravity and vessel element diameter for radial locations for micro, and fiber length for G3 (micro) for height, and specific gravity for radial location and fiber length for height for S7C15 clone for both the techniques. The clone L34 showed the significantly higher girth followed by G3 and S7C15. The variations were significant for girth, vessel element length and specific gravity between the wood produced from planting stocks grown by two techniques. Intra-clonal variations were significant for fiber length, fiber diameter and vessel element length. In general wood element’s dimensions and specific gravity increased from bottom to top and pith to periphery radial locations. G3 clone was different from the L34 and S7C15 clone for the wood traits. The three different clones of Populus deltoides showed variability in wood anatomical properties and specific gravity in the woods grown from macro- and micro-propagated planting stock. So, the plantation raised by two techniques could not produce similar type of wood even from the same clone. G3 clone was the exception as it did not show variation in wood traits for two techniques. Intra-clonal variations in all the three clones of P. deltoides indicated that wood traits were not stable within the population of same clone grown by either method.
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