Rhizome

Rhizome
A harvested ginger rhizome
A Euphorbia plant sending out rhizomes

In botany and dendrology, a rhizome (from Ancient Greek: rhízōma "mass of roots",[1] from rhizóō "cause to strike root")[2] is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes. Rhizomes may also be referred to as creeping rootstalks or rootstocks.

If a rhizome is separated into pieces, each piece may be able to give rise to a new plant. This is a process known as vegetative reproduction and is used by farmers and gardeners to propagate certain plants. Examples of plants that are propagated this way include hops, asparagus, ginger, irises, Lily of the Valley, Cannas, and sympodial orchids. Some examples of rhizomes that are used directly in cooking are ginger, turmeric, galangal, and fingerroot.

The Quaking Aspen (Populus tremuloides) is an example of a tree that propagates using a rhizome. Aspen clonal colonies in the American West, such as the large Pando colony in Utah, may have been living for over 1 million years. The rhizome of an aspen colony is the key to its longevity. Foragers, insects, fungus, and forest fires may destroy the above-ground portion of the tree, but the underground rhizome is somewhat protected against these threats.

A stolon is similar to a rhizome, but, unlike a rhizome, which is the main stem of the plant, a stolon sprouts from an existing stem, has long internodes, and generates new shoots at the end, such as in the strawberry plant. In general, rhizomes have short internodes; they send out roots from the bottom of the nodes and new upward-growing shoots from the top of the nodes. It is a method of reproduction for plants. A stem tuber is a thickened part of a rhizome or stolon that has been enlarged for use as a storage organ.[3] In general, a tuber is high in starch, for example, the common potato, which is a modified stolon. The term tuber is often used imprecisely, and is sometimes applied to plants with rhizomes.

Some plants have rhizomes that grow above ground or that lie at the soil surface, including some Iris species, and ferns, whose spreading stems are rhizomes. Plants with underground rhizomes include gingers, bamboo, the Venus Flytrap, Chinese lantern, Western poison-oak,[4] hops, and Alstroemeria, and the weeds Johnson grass, bermuda grass, and purple nut sedge. Rhizomes generally form a single layer, but in Giant Horsetails, can be multi-tiered.[5]

See also

References

  1. ^ ῥίζωμα. Liddell, Henry George; Scott, Robert; A Greek–English Lexicon at Perseus Project
  2. ^ ῥιζόω
  3. ^ Kingsley R. Stern Introductory Plant Biology, 10th ed. ISBN 0072909412
  4. ^ C.Michael Hogan (2008) Western poison-oak: Toxicodendron diversilobum, GlobalTwitcher, ed. Nicklas Stromberg Globaltwitcher.auderis.se
  5. ^ Husby, C: Ecology and Physiology of the Giant Horsetails, FIU.edu

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Look at other dictionaries:

  • RHIZOME — En morphologie végétale, un rhizome est une tige souterraine garnie de racines adventives, à feuilles réduites à des écailles ou absentes, et terminée par un bourgeon, souvent d’abord horizontal (portion rhizomateuse à sa première année), puis… …   Encyclopédie Universelle

  • Rhizome — Rhi*zome , n. [Gr. ??? the mass of roots (of a tree), a stem, race, fr. ??? to make to root, pass., to take root, fr. ??? a root: cf. F. rhizome.] (Bot.) A rootstock. See {Rootstock}. [1913 Webster] …   The Collaborative International Dictionary of English

  • rhizome — 1832, from Gk. rhizoma mass of tree roots, from rhizoun cause to strike root, from rhiza root, probably from PIE *wrad branch, root (Cf. L. radix root, O.N. rot root, O.E. wyrt plant, herb; se …   Etymology dictionary

  • rhizome — ► NOUN ▪ a horizontal underground plant stem with lateral shoots and adventitious roots at intervals. ORIGIN Greek rhiz ma, from rhiza root …   English terms dictionary

  • rhizome — [rī′zōm΄] n. [ModL rhizoma < Gr rhizōma < rhizousthai, to take root < rhiza,ROOT1] a creeping stem lying, usually horizontally, at or under the surface of the soil and differing from a root in having scale leaves, bearing leaves or… …   English World dictionary

  • rhizome —    by Felicity J.Colman    Rhizome describes the connections that occur between the most disparate and the most similar of objects, places and people; the strange chains of events that link people: the feeling of six degrees of separation , the… …   The Deleuze dictionary

  • rhizome —    by Felicity J.Colman    Rhizome describes the connections that occur between the most disparate and the most similar of objects, places and people; the strange chains of events that link people: the feeling of six degrees of separation , the… …   The Deleuze dictionary

  • Rhizome — Pour les articles homonymes, voir Rhizome (homonymie). Le rhizome d une plante est la partie souterraine et parfois subaquatique (ex : pour l iris pseudacorus) de la tige de certaines plantes vivaces …   Wikipédia en Français

  • rhizome — rhizomatous /ruy zom euh teuhs, zoh meuh /, adj. /ruy zohm/, n. Bot. a rootlike subterranean stem, commonly horizontal in position, that usually produces roots below and sends up shoots progressively from the upper surface. [1835 45; < NL rhizoma …   Universalium

  • rhizome — UK [ˈraɪzəʊm] / US [ˈraɪˌzoʊm] noun [countable] Word forms rhizome : singular rhizome plural rhizomes biology a thick plant stem that grows along the ground and produces roots and new plant growth …   English dictionary

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