View source for Polygonaceae

{{Treatment/ID
|accepted_name=Polygonaceae
|accepted_authority=Jussieu
|publications=
|common_names=Buckwheat Family
|basionyms=
|synonyms=
|hierarchy=Polygonaceae
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Polygonaceae]]</div></div>
|volume=Volume 5
|mention_page=page 217, 483, 528, 535, 602
|treatment_page=page 216
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Trees,</b> shrubs, vines, or herbs, perennial, biennial, or annual, homophyllous (heterophyllous in some species of <i>Polygonum</i>), polycarpic (rarely monocarpic in <i>Eriogonum</i>); roots fibrous or a solid or, rarely, chambered taproot, rarely tuberous. <b>Stems</b> prostrate to erect, sometimes scandent or scapose, solid or hollow, rarely with recurved spines (some species of <i>Persicaria</i>), glabrous or pubescent, sometimes glandular; nodes swollen or not; tendrils absent (except in <i>Antigonon</i> and <i>Brunnichia</i>); branches free (adnate to stems distal to nodes and appearing to arise internodally in <i>Polygonella</i>); caudex stems (subfam. Eriogonoideae) tightly compact to spreading and at or just below the soil surface or spreading to erect and above the soil surface, woody; aerial flowering stems prostrate or decumbent to erect, arising at nodes of caudex branches, at distal nodes of aerial branches, or directly from the root, slender to stout and solid or slightly to distinctly fistulose, rarely disarticulating in ringlike segments (<i>Eriogonum</i>). <b>Leaves</b> deciduous (persistent in <i>Coccoloba</i> and sometimes more than 1 year in <i>Antigonon</i>, <i>Eriogonum</i>, <i>Chorizanthe</i>, and <i>Polygonella</i>), basal or basal and cauline, rosulate, mostly alternate, infrequently opposite or whorled; stipule (ocrea) absent (subfam. Eriogonoideae, possibly vestigial in some perennial species of <i>Chorizanthe</i>) or present (subfam. Polygonoideae), persistent or deciduous, cylindric to funnelform, sometimes 2-lobed (<i>Polygonum</i>), chartaceous, membranous, coriaceous or partially to entirely foliaceous; petiole present or absent, rarely articulate basally (<i>Fagopyrum</i>, <i>Polygonella</i>, <i>Polygonum</i>), rarely with extrafloral nectaries (<i>Fallopia</i>, <i>Muehlenbeckia</i>); blade simple, margins entire, occasionally crenulate, crisped, undulate, or lobed, rarely awn-tipped (<i>Goodmania</i>). <b>Inflorescences</b> terminal or terminal and axillary, cymose and dichotomously or trichotomously branched, or racemose, umbellate, or capitate (subfam. Eriogonoideae); or spikelike, racemelike, paniclelike, cymelike, or, rarely, capitate (subfam. Polygonoideae), comprising simple or branched clusters of compound inflorescences; bracts absent (subfam. Polygonoideae), or 2–10+, usually connate proximally or to 1/2 their length, rarely perfoliate, foliaceous or scalelike, margins entire, sometimes awn-tipped (subfam. Eriogonoideae, rarely absent in <i>Eriogonum</i>), glabrous or pubescent; peduncle present or absent; clusters of flowers subtended by involucral bracts or enclosed in typically nonmembranous tubular involucres (subfam. Eriogonoideae) or subtended by connate bracteoles forming a persistent membranous tube (ocreola) (subfam. Polygonoideae). <b>Pedicels</b> present or absent, rarely accrescent (<i>Brunnichia</i>), articulate to flowers. <b>Flowers</b> usually bisexual, sometimes bisexual and unisexual on same or different plants, rarely unisexual only, 1–many, often with stipelike base distal to articulation; perianth persistent, often accrescent in fruit, often greenish, white, pink, yellow, red, or purple, rarely winged or keeled (<i>Fallopia</i> and some species of <i>Polygonum</i>), campanulate to urceolate, sometimes membranous, indurate (<i>Brunnichia</i> and <i>Emex</i>), or fleshy (<i>Coccoloba</i>, <i>Muehlenbeckia</i>, and some species of <i>Persicaria</i>) in fruit, rarely developing raised tubercles proximally (<i>Rumex</i>), glabrous or pubescent, sometimes glandular or glandular-punctate; tepals 2–6, distinct or connate proximally and forming tube, usually in 2 whorls, petaloid or sepaloid, dimorphic or monomorphic, rarely coriaceous (<i>Lastarriaea</i>), entire, emarginate, or lobed to laciniate apically, rarely awn-tipped (<i>Lastarriaea</i>); nectary a disk at base of ovary or glands associated with bases of filaments; stamens (1–)6–9, staminode rarely present; filaments distinct, or connate basally and sometimes forming staminal tube, free or adnate to perianth tube, glabrous or pubescent proximally; anthers dehiscing by longitudinal slits; pistil 1, (rudimentary pistil sometimes present in staminate flowers of monoecious or dioecious taxa), (2–)3(–4)-carpellate, homostylous (heterostylous in some species of <i>Fagopyrum</i> and <i>Persicaria</i>); ovary 1-locular (sometimes with vestigial partitions proximally); ovule 1, orthotropous or, rarely, anatropous, placentation basal or free-central; styles 1–3, erect to spreading or recurved, distinct or connate proximally; stigmas 1 per style, peltate, capitate, fimbriate, or penicillate. <b>Fruits</b> achenes, included or exserted, yellowish, brown, red, or black, homocarpic (sometimes heterocarpic in <i>Polygonum</i>), winged or unwinged, 2-gonous, 3-gonous, discoid, biconvex, lenticular, rarely 4-gonous or spheroidal, glabrous or pubescent. <b>Seeds</b> 1; endosperm usually abundant, mealy, development nuclear; embryo straight or curved, rarely folded.</span><!--

-->{{Treatment/Body
|distribution=Widespread;well represented in the north-temperate zone.
|discussion=<p>Genera 48, species ca. 1200 (35 genera, 442 species in the flora).</p><!--
--><p>Monophyly of <i>Polygonaceae</i> is well supported by molecular studies (M. W. Chase et al. 1993; P. Cuénoud et al. 2002; A. S. Lamb Frye and K. A. Kron 2003), which place it sister to Plumbaginaceae. Wood anatomy also supports this relationship (S. Carlquist 2003). <i>Polygonaceae</i> has been divided variously into subfamilies (S. A. Graham and C. E. Wood Jr. 1965; K. Haraldson 1978; J. Brandbyge 1993); two often are recognized based on morphological evidence: Eriogonoideae and Polygonoideae. Recent studies using the chloroplast gene rbcL suggest Eriogonoideae are monophyletic and Polygonoideae are paraphyletic (Lamb Frye and Kron). Generic limits have been much debated, particularly the circumscription of <i>Polygonum</i> in the broad sense. Morphological, cytological, palynological, and anatomical data, although useful in resolving some questions about the circumscriptions and relationships of genera, have not provided a consensus regarding relationships within the family. Pollen types (J. W. Nowicke and J. J. Skvarla 1977) and chromosome numbers (Brandbyge) are diverse. Multiple base chromosome numbers have been documented in some genera, and polyploidy is common. The classification used here generally follows J. L. Reveal (1978) for Eriogonoideae and Haraldson for Polygonoideae.</p><!--
--><p>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. A. Graham and C. E. Wood Jr. 1965). It is absent in subfamily Eriogonoideae except in some perennial, South American members of <i>Chorizanthe</i>, where it is rudimentary (J. L. Reveal 1978).</p><!--
--><p>The flowers of <i>Polygonaceae</i> have been studied extensively. Most researchers concluded that six tepals is the primitive condition in the family (R. A. Laubengayer 1937), but A. S. Lamb Frye and K. A. Kron (2003) concluded that five tepals is the primitive condition, and that taxa with six or four tepals evolved multiple times within the family. The same molecular study also suggested parallel evolution of growth forms and woodiness. Floral nectaries are useful generic characters in the Polygonoideae (L.-P. Ronse Decraene and J. R. Akeroyd 1988) but their utility in floristic treatments is limited because of their small size. In some genera of <i>Polygonaceae</i>, the outer tepals are connate and form a slender, stipelike hypanthium base above the articulation with the true pedicel. In the Polygonoideae treatments, pedicel refers to the true pedicel plus the stipelike hypanthium above the articulation; in Eriogonoideae, stipe refers only to the stipelike hypanthium base, and pedicel is applied only to the true pedicel.</p><!--
--><p>Members of the family are of relatively minor economic importance (A. N. Steward 1930; S. A. Graham and C. E. Wood Jr. 1965). <i>Fagopyrum</i> has been cultivated for millennia, <i>Coccoloba</i> produce edible fruits, and the petioles of <i>Rheum</i> and leaves of some species of <i>Rumex</i> are edible. Many species have been used as food or medicine or for ceremonies by various tribes of Native Americans. Outside the flora area, the family includes some tropical trees harvested for timber (<i>Coccoloba</i> and Triplaris). Some species of <i>Fallopia</i>, <i>Persicaria</i>, <i>Polygonum</i>, and <i>Rumex</i> are cosmopolitan weeds, and <i>Emex</i> is a pernicious weed in parts of the world. Of the 35 genera in the flora, four are entirely non-native: <i>Emex</i>, <i>Fagopyrum</i>, <i>Muehlenbeckia</i>, and <i>Rheum</i>. <i>Antigonon</i> and <i>Coccoloba</i> are popular ornamentals in the southern part of the flora region. Many species of <i>Erigonum</i> are planted in rock gardens. <i>Persicaria</i> species are important wetland plants because waterfowl consume their fruits.</p><!--
--><p>Mechanisms for achene dispersal vary greatly. Hooked or awned involucres occur in many genera of subfam. Eriogonoideae. The outer tepals of the perianth expand into wings (<i>Fallopia</i>) or spines (<i>Emex</i>), or the achene has wings (<i>Eriogonum alatum</i>, <i>Oxyria</i>, <i>Rheum</i>, and <i>Rumex</i>), which aid in dispersal by wind or water. The achenes are forcibly tossed from the plant in <i>Persicaria virginiana</i>, and persistent, hooked styles aid in their transport by animals. In <i>Coccoloba</i>, the fleshy tube of the tepals aids in dispersal by birds.</p>
|tables=
|references={{Treatment/Reference
|id=brandbyge1993a
|text=Brandbyge, J. 1993. Polygonaceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. 4+ vols. Berlin etc. Vol. 2, pp. 531–544.
}}{{Treatment/Reference
|id=carlquist2003a
|text=Carlquist, S. 2003. Wood anatomy of Polygonaceae: Analysis of a family with exceptional wood diversity. Bot. J. Linn. Soc. 141: 25–51.
}}{{Treatment/Reference
|id=frye-a
|text=Frye, A. S. and K. A. Kron. 2003. rbcL phylogeny and character evolution in Polygonaceae. Syst. Bot. 28: 326–332.
}}{{Treatment/Reference
|id=graham1965a
|text=Graham, S. A. and C. E. Wood Jr. 1965. The genera of Polygonaceae in the southeastern United States. J. Arnold Arbor. 46: 91–113.
}}{{Treatment/Reference
|id=jaretzky1928a
|text=Jaretzky, R. 1928. Histologische und karyologische Studien an Polygonaceen. Jahrb. Wiss. Bot. 69: 357–490. Lamb
}}{{Treatment/Reference
|id=laubengayer1937a
|text=Laubengayer, R. A. 1937. Studies in the anatomy and morphology of the polygonaceous flower. Amer. J. Bot. 24: 329–343.
}}{{Treatment/Reference
|id=roberty1964a
|text=Roberty, G. E. and S. Vautier. 1964. Les genres de Polygonacées. Boissiera 10: 7–128.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|- id="key-0-1"
|1
|Ocreae absent; nodes not swollen; flowers usually enclosed in involucres or subtended byinvolucral bracts, these rarely absent (in Gilmania)
|[[Polygonaceae subfam. Eriogonoideae|Polygonaceae subfam. Eriogonoideae]]
|- id="key-0-1"
|1
|Ocreae present, persistent or deciduous; nodes usually swollen; flowers not enclosed in involucres or associated with involucral bracts
|[[Polygonaceae subfam. Polygonoideae|Polygonaceae subfam. Polygonoideae]]
|}
</div></div><!--

-->{{#Taxon:
name=Polygonaceae
|author=Craig C. Freeman;James L. Reveal
|authority=Jussieu
|rank=family
|parent rank=
|synonyms=
|basionyms=
|family=Polygonaceae
|distribution=Widespread;well represented in the north-temperate zone.
|reference=brandbyge1993a;carlquist2003a;frye-a;graham1965a;jaretzky1928a;laubengayer1937a;roberty1964a
|publication title=
|publication year=
|special status=
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V5/V5_442.xml
}}<!--

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