TY - JOUR
T1 - Vegetative anatomy of the New Caledonian endemic Amborella trichopoda
T2 - Relationships with the Illiciales and implications for vessel origin
AU - Carlquist, S.
AU - Schneider, E. L.
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2001
Y1 - 2001
N2 - Light microscopy was used to study leaf hypodermis, vein sclerenchyma, stomatal subsidiary cell types, and stem and root xylem in liquid-preserved material of Amborella trichopoda; oblique borders on tracheid pits, scalariform end walls on tracheids, and porosities in end-wall pit membranes were studied with scanning electron microscopy. Amborella shares stomatal configurations, nodal type (in part), ray types, and porose pit membranes in tracheary elements with Illiciales s.l., but differs from that order in lacking oil cells, vessels, and grouped axial parenchyma cells. These data are consistent with a basal position in angiosperms for Amborella, and for a close relationship with, but not inclusion in, Illiciales; inclusion in a monofamilial order is conceivable. Both loss of pit membranes or pit membrane portions on end walls and increase in cell diameter are requisites for origin of vessels. Sarcandra and IIliciaceae show these early stages in origin of vessels. Amborella shows development of porosities in pit membranes. Vessel presence or absence may not be strictly bipolar, because some primitive vessel elements exhibit at least some tracheidlike characteristics and are thus transitional, and because changes in at least two characters define vessel origin.
AB - Light microscopy was used to study leaf hypodermis, vein sclerenchyma, stomatal subsidiary cell types, and stem and root xylem in liquid-preserved material of Amborella trichopoda; oblique borders on tracheid pits, scalariform end walls on tracheids, and porosities in end-wall pit membranes were studied with scanning electron microscopy. Amborella shares stomatal configurations, nodal type (in part), ray types, and porose pit membranes in tracheary elements with Illiciales s.l., but differs from that order in lacking oil cells, vessels, and grouped axial parenchyma cells. These data are consistent with a basal position in angiosperms for Amborella, and for a close relationship with, but not inclusion in, Illiciales; inclusion in a monofamilial order is conceivable. Both loss of pit membranes or pit membrane portions on end walls and increase in cell diameter are requisites for origin of vessels. Sarcandra and IIliciaceae show these early stages in origin of vessels. Amborella shows development of porosities in pit membranes. Vessel presence or absence may not be strictly bipolar, because some primitive vessel elements exhibit at least some tracheidlike characteristics and are thus transitional, and because changes in at least two characters define vessel origin.
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U2 - 10.1353/psc.2001.0020
DO - 10.1353/psc.2001.0020
M3 - Article
AN - SCOPUS:0034880854
SN - 0030-8870
VL - 55
SP - 305
EP - 312
JO - Pacific Science
JF - Pacific Science
IS - 3
ER -