El. Schneider et S. Carlquist, Origin and nature of vessels in monocotyledons. 4. Araceae subfamily Philodendroideae, J TORREY B, 125(4), 1998, pp. 253-260
Tracheary elements of roots and rhizomes of five species of Araceae, subfam
ily Philodendroideae, representing five of the seven tribes of the subfamil
y, were studied by means of SEM, using macerations supplemented by sections
. All except Zantedeschia albo-maculata and possibly Anthurium scherzerianu
m proved to have vessels in rhizomes as well as roots; only vessels in root
s have been previously reported for the family. Perforation plates of rhizo
mes differ little from those of roots, although in some of the species pit
membrane remnants are more conspicuous in rhizome perforation plates. The w
ell-defined perforation plates of Anthurium may be related to conduction wh
en water is available in terrestrial and epiphytic habitats that dry season
ally. Likewise, the root vessels of Zantedeschia may be related to rapid co
nduction during wet periods. Vessel elements of subfamily Philodendroideae
represent features regarded as primitive, most notably, similarity between
perforations and lateral wall pits, and the presence of pit membrane remnan
ts in perforations. Pit membrane remnants likely are little impediment to c
onduction in moist tropical understory localities where most aroids grow.