Analysis of briquettes and pellets obtained from two types of Paulownia (Paulownia tomentosa and Paulownia elongata) sawdust

Sawdust specimens of two Paulownia species, namely Paulownia tomentosa and Paulownia elongata, were evaluated in order to obtain briquettes and pellets. Briquettes and pellets were manufactured from the sawdust, and their physical properties (density), mechanical properties (the resistance of the briquettes to breaking, and the shear resistance of the pellets), and energetic properties (caloric value, black ash content, and calcined ash content) were determined. The densities of the P. elongata and P. tomentosa briquettes were 790 kg/m3 and 934 kg/m3, respectively, while the pellets had densities of 1268 kg/m3 and 1266 kg/m3, respectively. These values were within the standardized limits, and the ash content had good values. The high calorific value of 16815 kJ/kg and the low calorific value of 16669 kJ/kg was acceptable, since they were greater than other vegetable resources. In conclusion, it was found that the two types of wood biomass are suitable for the production of briquettes and pellets, due to their good physical, mechanical, and energetic properties.

Genetic transformation of Paulownia elongata S. Y. Hu., mediated by Agrobacterium tumefaciens and biolistic system

Objective: The most appropriate conditions for genetic transformation through direct (bioballistic) and indirect (Agrobacterium tumefaciens) transformation systems in Paulownia elongata were established. Design/methodology/approach: Starting from in vitro propagation through both direct and indirect organogenesis, internodal stem segments with 0.5 to 1 cm length were determined as the best explant. The optimum dose for selection media was determined to be 15 mg L-1 of kanamycin. It was possible to obtain transgenic plants under both transformation systems. In the case of Agrobacterium tumefaciens, two hours of incubation, 48 h of co-cultivation, and optical density of 0.9 were used; while for bioballistics, the best conditions were 120 PSI of shot pressure, shot height at level 6 (16 cm), and vacuum pressure of 22 Hg mm, with particle inflow gun system (PIG). Results: Both systems produced complete transformants, chimeras, as well as those confirmed by histochemical X-GLUC and PCR analysis, producing a total of 14 positive plants by A. tumefaciens transformation from 26 trials and ten positive plants by the bioballistic system from 30 trials; a construction with chitinase and glucanase, NPT II selection gene and the GUS reporter gene were used. Findings/conclusions: So far, this has been the first report including integration of chitinase and glucanase genes.

Potencial energético de clones de Paulownia y Miscanthus para la producción de energía en Chile

El modelo energético mundial se basa en combustibles fósiles, el cual ha venido siendo sustituido por consideraciones ambientales y económicas, dándole paso a la biomasa y a las plantaciones dendroenegéticas. En Chile, las energías renovables no convencionales (ERNC) vienen ganando espacio, además la nación ha abocado esfuerzos en especies que posean buen potencial energético. Así, este estudio tiene como objetivo evaluar el potencial físico-químico, energético y perfiles térmicos de dos especies (Paulownia elongata x fortunei y Miscanthus x giganteus) para el uso energético en tres sitios contrastantes de Chile. Los análisis fueron realizados en su mayoría bajo los estándares de las Normas DIN. Los resultados para Paulownia mostraron diferencias entre los sitios, obteniendo los mejores resultados en el sitio El Vergel con un porcentaje de lignina de 34,84%, cenizas de 1,16%, material volátil de 81,70%, carbono de 47,02% y una densidad energética líquida (DEL) de 2,16 GJ m-3. Para Miscanthus los mejores resultados también fueron registrados en El Vergel, con porcentaje de lignina de 30,60%, cenizas de 2,84%, material volátil de 82,26% y carbono de 45,97% y una DEL de 1,67 GJ m-3, destacando que los mejores resultados de El Vergel son para la densidad D1. Respecto al perfil térmico (TGA-DTG), la Paulownia presentó pérdida de masa mayor que el Miscanthus y tuvo ignición a menor temperatura de 197,76 °C y 209,66 °C respectivamente. Por lo tanto, el mayor porcentaje de residuo lo presentó el Miscanthus con 5,63%. Consiguientemente, ambas especies presentan características deseables para su uso energético.

Respuesta de material genético de Paulownia spp a tratamiento silvicultural, como estrategia para evaluar su adaptabilidad a condiciones climáticas de estepa espinosa Montano Bajo, Ecuador/Response of Paulownia spp genetic material to silviculture, as a s

El propósito de la investigación consistió en estudiar la respuesta de Paulownia elongata, P. fortunei y un híbrido (Paulownia fortunei x elongata) a un sistema de recepa y evaluar el desempeño de los brotes juveniles, como estrategia para confirmar su adaptabilidad a las condiciones bioclimáticas de estepa espinosa Montano Bajo. El ensayo se instaló en diciembre del 2 015, en una plantación clonal de dos años de edad, plantada por INIAP y ESPOCH en la granja Tunshi, Ecuador. Se establecieron 9 bloques por especie para un total de 27 parcelas experimentales, con 9 observaciones por parcela neta. El tratamiento silvicultural ejecutado fue poda de renovación/recepa, realizando un corte del tallo en bisel a dos centímetros de altura desde el suelo. Las variables evaluadas fueron: Días a la brotación, número de brotes por tocón, diámetro a la base del brote y altura del brote. Los tres materiales estudiados respondieron positivamente a la práctica silvicultural, 90% de tocones brotados a los 61 días de haber realizado el ensayo. A los 29 días de la recepa ya se encontraron brotes epicórmicos en las tres especies de Paulownia, presentando entre 1 y 13 brotes por tocón. En crecimiento dasométrico, P. fortunei experimentó el mayor promedio en altura (81,85 cm), seguida por P. elongata (70,51 cm) y Paulownia hibrido (65,53 cm), siendo 3,5 veces mayor a los promedios de altura y 4 veces mayor en diámetro a la altura de la base del tallo, de los reportados en el primer año de evaluación. Estos resultados avizoran probables comportamientos adecuados y adaptación como una especie forestal-agroforestal de interés para características similares del sitio de estudio. This study is aimed to evaluate the response Paulownia elongata, P. fortunei and hibrid (Paulownia fortunei x elongata) to renewal pruning system and evaluate to develop the juvenile sprout of plants as a strategy to assess its adaptability to the bioclimatic conditions of thorny steppe Montano Bajo, Ecuador. The essay was install in December, 2 015 in one clonal plantation two years old, establish by INIAP and ESPOCH in Tunshi farm, Ecuador. This was established in nine blocks per species for a total of 27 experimental plots with nine observations per net plot. The selviculture treatment executed was renewal pruning, making a bevel cut stem two feet high from the ground. The variables evaluated were: Days sprouting, number of sprouts per stump diameter at the base of the outbreak and height of the outbreak. The three materials studied responded positively to silvicultural practice and 90% of erupted stumps at 61 days responded to development essay. At 29 days from the development the recepa presented epicormics sprout in the three Paulownia species; P. fortunei experienced the greatest average height (81,85 cm), followed by P. elongata (70,51 cm) and hybrid Paulownia (65,53 cm), being 3,5 times greater than the average height and 4 times greater in diameter at the base than those reported in the first year evaluation, these results foresee probable behaviors adapted and adequate as a forestry-agroforestry species of interest from the site of study. Palabras clave: recepa, poda, silvicultura, dendroenergía. Keywords: recepa, pruning, silviculture, wood energy.

Digestibility and energy content of Paulownia (Paulownia elongata S.Y.Hu) leaves

The aim of the study was to determine the digestibility and energy content of Paulownia elongata S.Y.Hu leaves after leaf fall. Leaves together with petioles were dried at room temperature and milled with a roughage mill before feeding to animals. A classical digestion trial was performed, with three rams weighing 55.4kg on average, by determining the chemical composition of consumed feed, feed leftovers and excreted faeces. Digestibility was evaluated as difference in the amount of ingested nutrients and nutrients excreted with faeces and it was determined to be 50.72, 52.08, 31.63, 54.09, 55.15 and 56.06% for dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), crude fibre (CF) and nitrogen-free extract (NFE). The energy value for ruminants calculated on the basis of chemical composition and established digestibility was 8.29 MJ digestible energy (DE)/kg DM, 6.55 MJ metabolizable energy (ME)/ kg DM, 0.59 feed units for milk (FUM)/kg DM and 0.52 feed units for growth (FUG)/kg DM.