Abstract Detail

Systematics Section / ASPT

Vrijdaghs, A. [1], Caris, P. [1], Goetghebeur, P. [2], Smets, E. [1].

The bristles of Dulichium (Cyperaceae), a floral ontogenetic study.

The Dulichieae are a small tribe of three genera within the subfamily Cyperoideae. They are considered to be the link between the Cyperoideae and the Caricoideae because of the presence of a flower in the spikelet prophylls. A recent molecular phylogenetic analysis confirms this view (Simpson et al. Phylogeny of Cyperaceae based on DNA sequence data - a new rbcL analysis. Proceedings of Monocots III/Grasses IV, Rancho Santa Ana Botanic Garden, California. In press). Within the Cyperoideae, the flowers of the more primitive (scirpoid) genera are built up according to a typical monocotyledonous pentacyclic pattern, with two whorls of three perianth parts, two whorls of three stamens (although in most genera only one whorl of three stamens remains), and a tricarpellate gynoecium. Modifications and reductions in number of all floral parts are quite common in the subfamily. According to the euanthium or synanthium hypotheses, the flowers of Dulichium, which have eight bristles, have been interpreted in different ways. Our floral ontogenetic study proves unambiguously that the “bauplan” of flowers in D. arundinaceum is derived within Cyperoideae, but that a typical scirpoid pattern can still be recognised in the course of the floral ontogeny.

Related Links:
Laboratory of Plant Systematics

1 - Laboratory of Plant Systematics, K.U.Leuven, Department of Biology, Kasteelpark Arenberg 31, Leuven, B-3001, Belgium
2 - Research Group Seed Plants & Flowering Plants, Department of Biology, Ledeganckstraat 35, Gent, B-9000, Belgium

Keywords:
Cyperaceae
Dulichium
Floral ontogeny
perianth
SEM.

Presentation Type: Poster
Session: 32-85
Location: Special Event Center (Cliff Lodge)
Date: Tuesday, August 3rd, 2004
Time: 12:30 PM
Abstract ID:425