Polygonacées - Polygonaceae. Polygonaceae. Contents Size; Distribution; Importance; Morphology; Taxonomy Bio 3400 Home Page The Polygonaceae includes many herbs, a number of shrubs, and a few trees. It is a medium-sized family, with 30 genera and 750 species, most of which occur in the north temperate region of the world. We have 31 native species in northern Utah, most being species of Eriogonum. Many species are mentioned as ornamentals in European garden catalogs, but few are cultivated as ornamentals in this part of the world. There would seem to be an opportunity here for someone interested in developing ornamental cultivars from our native species, most of which are well-suited to arid climates, i.e., xerophytic gardening, the latest "thing" in gardening as water shortages threaten to become common (too many people drinking, taking showers, flushing toilets, etc.)
Members of the Polygonaceae may be herbs, shrubs, trees or vines. Polygonaceae in Flora of North America. 44. Polygonaceae Jussieu Buckwheat Family Craig C. Freeman, James L. Reveal Trees, shrubs, vines, or herbs, perennial, biennial, or annual, homophyllous (heterophyllous in some species of Polygonum), polycarpic (rarely monocarpic in Eriogonum); roots fibrous or a solid or, rarely, chambered taproot, rarely tuberous. Genera 48, species ca. 1200 (35 genera, 442 species in the flora): widespread, well represented in the north-temperate zone. Monophyly of Polygonaceae is well supported by molecular studies (M. A characteristic feature of the family is the ocrea, a nodal sheath variously interpreted as an outgrowth of the sheathing base of the petiole, as connate stipules, or as an expanded axillary stipule (S. The flowers of Polygonaceae have been studied extensively. Members of the family are of relatively minor economic importance (A.
Mechanisms for achene dispersal vary greatly. Brandbyge, J. 1993. List of lower taxa. Flowering Plant Families, UH Botany. The Polygonaceae are herbs, shrubs, or rarely trees comprising about 30 genera and 1,000 species. The leaves are simple, alternate or rarely opposite, and usually stipulate. The membranous, sheathing stipule is called an ocrea. The flowers are actinomorphic, usually small, and are bisexual or occasionally unisexual. The perianth is usually in two undifferentiated whorls comprising 3-6 distinct or basally connate tepals. The androecium consists of 6-9, commonly 8 distinct or basally connate stamens, usually in two whorls.
The gynoecium consists of a compound pistil of usually 3 carpels, an equal number of style branches or styles, and a superior ovary with one locule containing a single basal ovule. Each "thumbnail" image below is linked to a larger photograph. Plant Family Access PageHome Page. Polygonaceae. The Polygonaceae comprise about 1200 species[3] distributed into about 50 genera.
The largest genera are Eriogonum (240 species), Rumex (200 species), Coccoloba (120 species), Persicaria (100 species) and Calligonum (80 species).[4][5] The family is present worldwide, but is most diverse in the North Temperate Zone. Polygonaceae contain some of the worst weeds, including species of Persicaria, Emex, Rumex, and Polygonum, such as Japanese knotweed.[3] Taxonomy[edit] Description[edit] Genera[edit] Lists of genera of Polygonaceae can be found on the internet.[18][19][20] In the list below, the first three columns are the 43 genera described by Brandbyge in The Families and Genera of Vascular Plants.
Phylogeny[edit] The following phylogenetic tree is based on two papers on the molecular phylogenetics of Polygonaceae.[11][12] References[edit] External links[edit] Polygonaceae. PolygonaceaeJussieu Familles incluses de Polygonaceae Coccolobaceae, Eriogonaceae, Rumicaceae Distribution de Polygonaceae Les Polygonaceae sont des plantes cosmopolites, qui ont une préférence marquée pour les zones tempérées et froides de l'hémisphère Nord. Toutefois, quelques genres sont propres à l'hémisphère Sud : Oxygonum à Madagascar et en Afrique australe ; Muehlenbeckia en Australie et en Nouvelle-Zélande ; Antigonon au Mexique et en Amérique centrale et Coccoloba en Amérique tropicale.
Appareil végétatif des Polygonaceae Ce sont sont des herbes vivaces, bisannuelles ou annuelles, des lianes, des arbustes ou de petits arbres plus ou moins persistants. La polycarpie est de règle, mais certaines espèces d'Eriogonum sont monocarpiques. Les racines sont fibreuses, rarement tubéreuses. La tige est caractérisée par la présence d'un ochrea, constitué par les stipules concrescentes formant un manchon plus ou moins scarieux au-dessus de l'insertion pétiolaire. Anatomie des Polygonaceae. Caryophyllales.
EMBRYOPSIDA Pirani & Prado Many of the bolded characters in the characterization above are apomorphies of subsets of streptophytes along the lineage leading to the embryophytes, not apomorphies of crown-group embryophytes per se. All groups below are crown groups, nearly all are extant; characters mentioned are those of the common ancestor of the group. Abscisic acid, ? D-methionine +; sporangium with seta, seta developing from basal meristem [between epibasal and hypobasal cells], sporangial columella + [developing from endothecial cells]; stomata +, anomocytic, cell lineage that produces them with symmetric divisions [perigenous]; underlying similarities in the development of conducting tissue and in rhizoids/root hairs; spores trilete; polar transport of auxins and class 1 KNOX genes expressed in the sporangium alone; MIKC, MI*K*C* and class 1 and 2 KNOX genes, post-transcriptional editing of chloroplast genes; gain of three group II mitochondrial introns.
Age. Evolution. Phylogeny. Non-core Caryophyllales. Pam Soltis, Doug Soltis, and Monica Arakaki Click on an image to view larger version & data in a new window Introduction The non-core Caryophyllales clade (sensu Cuénoud et al. 2002), which corresponds to the Polygonales of Judd et al. (2002), has only recently been identified through molecular phylogenetic analysis. It includes several families that were previously classified in Cronquist’s (1981) Rosidae or Dilleniidae. Characteristics Possible synapomorphies for the non-core Caryophyllales (= Polygonales sensu Judd et al. 2002) are scattered secretory cells containing plumbagin, naphthaquinone (which has been lost in several clades), an indumentum of stalked, gland-headed hairs, basal placentation (with shifts to parietal in some Droseraceae and axile in Nepenthaceae), and starchy endosperm (Judd et al. 2002).
Discussion of Phylogenetic Relationships There are three major clades within non-core Caryophyllales: Other Names for non-core Caryophyllales Polygonales References Albert, V. Judd, W.