Inflorescence structure and generic delimitation of Triplaris and Ruprechtia (Polygonaceae)

Abstract

A revision of the generic limits between Triplaris and Ruprechtia (Polygonaceae), which were confused in earlier literature. led to the conclusion that the two genera should be maintained. Triplaris is characterized by 1-flowered pistillate partial intlorescences, absence of a basal pedicel-like extension of the fruiting perianth-tube, which is always as long as or longer than the achene, bracteoles completely fissured on the ahaxial side, and sessile or subsessile male flowers with perianth segments always connate for more than half of their length. Ruprechtia has 2-3-flowered monochasial pistillate part-inflorescences (except the 1 -flowered R. triflora). a basal pedicel-like extension of the fruiting perianth-tube. which is at most 3/4 as long as the achene, more or less tubular bracteoles only exceptionally fissured down on the ahaxial side, and pedicellate male flowers with perianth segments never connate for more than one third of their lenght. Preliminary palynological studies have shown that the pollen of Triplaris are microreticulate or punctate-microreticulate while Ruprechria pollen have perforate-rugulose surfaces.J . Brandbyge and B . 0llgaard, Botanical Insr., Univ. of Aarhus, Nordlandsvej 68, DK-8240 Risskov. Denmark.

Genome duplication effects on functional traits and fitness are genetic context and species dependent: studies of synthetic polyploid Fragaria

“…is at the base of the clade but without strong support. Because of the morphological gradation between many characters, generic circumscription has been a taxonomic issue for these genera (Cocucci, 1961; Roberty and Vautier, 1964; Brandbyge and Øllgard, 1984; Pendry, 2004). One of the diagnostic characters that has been used is the extent to which the accrescent hypanthium is fused to cover the achene (Cocucci, 1961), a quantitative character.…”

Taxonomy of Polygonoideae (Polygonaceae): A new tribal classification

“…Additional taxonomic characters are common in Polygonaceae, but often overlooked. There is an articulation between the pedicel and stipe (Haraldson, 1978;Freeman & Reveal, 2005), the primary inflorescence type is cymose (cluster-like dichasia or helicoid cymes, Brandbyge & Øllgard, 1984;Brandbyge, 1993), and nectaries are common. Nectar is often produced copiously and can be either externally exuded through discs, glands or papillae, or secreted perigonally (Ronse De Craene & Akeroyd, 1988;Ronse De Craene & Smets, 1991).…”

Macro-, micromorphological characters and DNA fingerprinting markers on three Ruprechtia species (Polygonaceae) in Egypt

“…During a taxonomic study of the neotropical genus Triplaris Loefl. Ex L. Brandbyge and Øllgaard (1984), realized that the generic delimitation between Triplaris and Ruprechtia had been confused in earlier literature and was in need of a new evaluation.…”

“…Ruprechtia is a genus of small trees or shrubs from neotropical dry and riverine forests. Brandbyge and Øllgaard (1984) and Brandbyge (1984 and1986), reported that this genus has been closely allied with Triplaris, but differs in its two-or three-pistillate partial inflorescence, a basal pedicel-like extension of the perianth tube in fruit, and pedicellate male flowers with perianth segments connate for less than a third of their length. It also typically has fewer pairs of secondary leaf veins (less than 12) than Triplaris, smaller leaves, and achenes loosely enclosed within the fruiting perianth, the inflorescences are mostly axillary.…”

“…Praglowski and Punt (1973); Nowicke and Skvarla (1977) and Hong (1995), showed that pollen grains have perforate-rugose surfaces which appear slightly spinulose in some species. Brandbyge and Øllgaard (1984), studied the inflorescence structure to make generic delimitation of Triplaris and Ruprechtia. Many studies on Ruprechtia as a new genus has been carried out.…”