LIGNIFICATION OF WOOD FROM DEFORMED PINUS-RADIATA

Deformed trees with significantly lower concentrations of copper in foliage than straight trees were also found, by both chemical and histochemical analysis, to have significantly lower lignin contents in earlywood tissue than straight trees. Regions of traumatic tissue were also observed in wood from some of the deformed trees. Deformed trees exhibiting the Toorour syndrome (deformed stems but apparently adequate Cu concentrations in foliage), had concentrations of Cu in foliage and lignin content of current woody tissue similar to that in paired straight trees. There was no evidence of traumatic tissue formation in earlywood from deformed trees. We suggest that stem deformity in Cu deficiency is due to stems weakened by low lignin content of earlywood. Stem deformity in the Toorour syndrome is more difficult to explain; it appears not to be due to low lignin content, but is likely to be due to structural aspects of the cell wall. © 1990.