Tension Wood and Normal Wood Formation and Lignification in Some Eucalypts.
2008
A`ssareh, Mohammad Hassan | Toghraei, Nushin | Prsa Pazhuh, Davud | Mir Shokraei, Ahmad | Saleheh Shushtari, Mohammad Hassan | Matini Zadeh, Mohammad
One of the fast growth disadvantages is known to be reaction wood formation in tree stems and branches. In this stuy, tracing wood cell formation and cell wall lignification and also the role of some enzymes in this process had been investigated. Making young trees experimentally form tension wood, led us to investigate tension wood formation in different morphological zones of the stems in variable periods of time. Although there were different genetical classes, the following items can include all the specimens: - Eucalyptus camaldulensis, E. gunnii, E. globulus, E. viminalis and E.microtheca are able to produce tension wood in the form of gelatinous fibers naturally- Young trees of eucalypt, reacted to experimentally bending immediately in the form of: Gelatinous fibers differentiation at the top of the stemsPith eccentricity at the same directionGelatinous fibers in xyem tissueSlowing down the rate of vessels production. 62- At first the reaction was very high but it was slowed down along continuing stem tilting. - Branch preferred angle was regulated by tension Wood formation at bottom and later at the top of the branch. - There was no evidence of tree recovery of orientation, after cutting off the apical meristem. - Immediate transition to gelatinous fibers was noticed not to neglect the very possible role of the cells themselves instead of cambium.
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