Ligule

Ligule

A ligule (from Latin "ligula", diminutive of "liga") can be observed in the leaf of a grass. It is a thin outgrowth at the junction of leaf and leafstalk.

The ligule is found at the inner base of the leaf between where the leaf attaches to the main stem and the stem itself. It may take several forms but is commonly some form of translucent membrane or a fringe of hairs. The membranous ligule can be very short 1–2 mm (Kentucky Bluegrass, "Poa pratensis") to very long 10–20 mm (Johnson grass, "Sorghum halepense"), it can also be smooth on the edge or very ragged. Some grasses do not have a ligule, for example barnyardgrass ("Echinochloa crusgali").

A ligule can also be defined as a membrane-like tissue or row of delicate hairs typically found in grasses at the junction of the leaf sheath and blade. The ligule appears to be a continuation of the leaf sheath and encircles or clasps the stem as does the leaf sheath. There are three basic types of ligules: membranous, a fringe of hairs (ciliate), and absent or lacking. Most grasses have ligules, and the shape, length, and appearance of the ligule margin provide consistent characters for separating genera and some species of grasses. In grass-like plants such as sedges (Cyperaceae) and rushes (Juncaceae), ligules are usually absent or poorly developed.

Ligules are also present in some non-grass species such as members of Asteraceae.


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  • ligule — [ ligyl ] n. f. • 1562; lat. ligula, var. de lingula, dimin. de lingua → langue ♦ Bot. Ligule foliaire : languette membraneuse à la face supérieure des feuilles de certaines plantes. Ligule florale : languette de la corolle des composées. ●… …   Encyclopédie Universelle

  • ligulé — ligule [ ligyl ] n. f. • 1562; lat. ligula, var. de lingula, dimin. de lingua → langue ♦ Bot. Ligule foliaire : languette membraneuse à la face supérieure des feuilles de certaines plantes. Ligule florale : languette de la corolle des composées.… …   Encyclopédie Universelle

  • Ligule — sur une feuille de graminée (Alopecurus geniculatus) La ligule désigne chez les Poaceae, les Selaginellaceae et quelques Cyperaceae une pièce pièce foliaire correspondant à une languette membraneuse ou parfois une rangée de poils située à la… …   Wikipédia en Français

  • Ligule — Lig ule (l[i^]g [ u]l), n. [L. ligula, lingula, little tongue, dim of lingua tongue : cf. F. ligule.] 1. (Bot.) (a) The thin and scarious projection from the upper end of the sheath of a leaf of grass. (b) A strap shaped corolla of flowers of… …   The Collaborative International Dictionary of English

  • ligulé — ligulé, ée (li gu lé, lée) adj. Terme de botanique. Qui a la forme d une bande étroite, d une ligule …   Dictionnaire de la Langue Française d'Émile Littré

  • ligule — [lig′yo͞ol] n. [L ligula, a spoon, tongue of a shoe, shoe strap < IE base * leiğh , to lick > MIr liag, LICK: infl. by assoc. with L lingua, tongue, ligare, to bind] 1. a strap shaped corolla in the flowers of certain composite plants 2. a… …   English World dictionary

  • ligule —   n. thin outgrowth at junction of leaf and leafstalk.    ♦ ligulate, a. having ligule; strap shaped.    ♦ liguloid, a. like ligule …   Dictionary of difficult words

  • LIGULÉ, ÉE — adj. T. de Botanique Qui est pourvu d’une ligule. Feuille ligulée …   Dictionnaire de l'Academie Francaise, 8eme edition (1935)

  • ligule — noun Etymology: New Latin ligula, from Latin, small tongue, strap, from lingere to lick more at lick Date: circa 1847 a scalelike projection especially on a plant: as a. a thin appendage of a foliage leaf and especially of the sheath of a blade… …   New Collegiate Dictionary

  • LIGULE — n. f. T. de Botanique Appendice de la feuille des graminées …   Dictionnaire de l'Academie Francaise, 8eme edition (1935)

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