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    Author(s): Roland Dute; Lauren Bowen; Sarah Schier; Alexa Vevon; Troy Best; Maria Auad; Thomas Elder; Pauline Bouche; Steven Jansen
    Date: 2014
    Source: International Association of Wood Anatomists 35(3), 217-235
    Publication Series: Scientific Journal (JRNL)
    Station: Southern Research Station
    PDF: Download Publication  (861.0 KB)


    Bordered pit pairs of Ephedra species were characterized using different types of microscopy. Pit membranes contained tori that did not stain for lignin. SEM and AFM views of the torus surface showed no plasmodesmatal openings, but branched, secondary plasmodesmata were occasionally noted using TEM in conjunction with ultrathin sections. The margo consisted of radial microfibrils as well as finer diameter tangential fibrils. The former formed fascicles of fibrils that merged into even thicker buttresses during the act of pit membrane aspiration. AFM showed a discontinuous layer of non-microfibrillar material on the surface of both torus and margo. It is hypothesized that this material is responsible for adhesion of the pit membrane to the surface of the pit border during the process of aspiration. Taken as a whole, intervascular pit membranes of Ephedra more closely resemble those of conifers than those of torus-bearing pit membranes of angiosperms.

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    Dute, Roland R.; Bowen, Lauren A.; Schier, Sarah; Vevon, Alexa G.; Best, Troy L.; Auad, Maria; Elder; Thomas; Bouche, Pauline; Jansen, Steven. 2014. Pit membranes of ephedra resemble gymnosperms more than angiosperms. International Association of Wood Anatomists 35(3), 217-235 19 p.


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    Keywords: Atomic force microscopy, margo, plasmodesmata, scanning electron microscopy, torus, transmission electron microscopy.

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