Abstract

Gelatinous fibers (G-fibers) are the active component of tension wood. G-fibers are unlike traditional fiber cells in that they possess a thick, nonlignified gelatinous layer (G-layer) internal to the normal secondary cell wall layers. For the past several decades, the G-layer has generally been presumed to be composed nearly entirely of crystalline cellulose, although several reports have appeared that disagreed with this hypothesis. In this report, immunocytochemical techniques were used to investigate the polysaccharide composition of G-fibers in sweetgum (Liquidambar styraciflua; Hamamelidaceae) and hackberry (Celtis occidentalis; Ulmaceae) tension wood. Surprisingly, a number of antibodies that recognize arabinogalactan proteins and RG I-type pectin molecules bound to the G-layer. Because AGPs and pectic mucilages are found in other plant tissues where swelling reactions occur, we propose that these polymers may be the source of the contractile forces that act on the cellulose microfibrils to provide the tension force necessary to bend the tree trunk.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.