Resumen de Determination of differences in anatomical and chemical characteristics of tension and opposite wood of 8-year old "Eucalyptus globulus"
María G. Aguayo, Licarayen Quintupill, Rosario Castillo, Jaime Baeza Hernández, Juanita Freer, Regis T. Mendonça
Tension and opposite wood, divided in the corresponding heartwood and sapwood regions,from 8-year old Eucalyptus globulus trees were characterized for chemical composition and fibreanatomy in the transverse section in order to identify the main differences. Thicker and poorly lignifiedcell walls were found in tension wood. Cellulose content was similar for both woods, although tensionwood contained 30% higher xylose and 15% less lignin than opposite wood. Lignin of tension woodcontained 24% more syringyl units and a higher frequency of ß-O-4 linkages. Principal componentanalysis (PCA) performed separately with anatomical and chemical data showed a clear separationbetween tension and opposite wood. The principal characteristics used for separation were: cell wallthickness, vessel diameter, lumen diameter, lignin and xylose content, and amount of syringyl units.Keywords: Tension wood, Eucalyptus globulus, carbohydrates, lignin, wood anatomy.
