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Feather Zwenke (Brachypodium pinnatum), illustration

Feather Zwenke ( Brachypodium pinnatum ), illustration

Systematics
Commelinids
Order : Sweet grass (Poales)
Family : Sweet grasses (Poaceae)
Subfamily : Pooideae
Tribe : Brachypodieae
Genre : Think
Scientific name
Brachypodium
P.Beauv.
Brachypodium distachyon
Horst of Brachypodium phoenicoides
Brachypodium retusum
Forest Zwenke ( Brachypodium sylvaticum )

The Zwenken ( Brachypodium ) are a genus of sweet grasses (Poaceae).

description

Vegetative characteristics

The Zwenken are usually persistent , rarely (only Brachypodium distachyon ) annual, clump or lawn-forming grasses. Most species have rhizomes . They can have subterranean runners. The non-flowering shoots grow up intra- or extravaginally. The stems stand upright or kneeling-ascending and are more knotty . The stem nodes are hairy, the internodes hollow. The vascular bundles in the internodes are in three circles. The stalks reach heights of 2 to 200 centimeters.

The leaf sheaths are open to the base. The ligula is tongue or collar-shaped, as well as truncated or rounded. The leaf blade is rolled in the bud position , otherwise flat-spread. The blade is bald or hairy. The vascular bundles cause the upper side of the leaf to be ribbed. The midrib is not prominent. The sclerchyme is always associated with the vascular bundles.

Generative characteristics

The inflorescence is a loose raceme with one to twelve spikelets. These are short (0.5 to 3 millimeters) stalked, two-sided or all-sided. They are protruding or adjacent, alternate and turn the broad side of the ear axis. The spikelet has 3 to 60 flowers. All are hermaphroditic. The florets fall out individually from the remaining glumes when they ripen. The glumes are unequal, pointed, awn-pointed or with a short awn . The lower glume has three to seven nerves. The lemmas are five- to nine-veined, with entire margins above, as well as pointed or tapering into an awn. The awn is straight or curled. The palea are two-veined and slightly shorter than the lemma.

The Zwenken have three stamens with anthers 1 to 6 millimeters long . The top of the ovary is covered with short hair. It has two terminal, short styluses and a long, feathery stigma . All species except Brachypodium distachyon show self-incompatibility .

The fruit (caryopsis) has a narrow elliptical outline. It has narrow skin margins at the top and is sickle-shaped in cross section. The embryo takes up about a fifth of the fruit length. The endosperm is hard, fat-free and consists of simple starch grains . The umbilical spot (hilum) is linear and about as long as the fruit.

Chromosome number

The basic chromosome number is x = 5, 7, 9 and 10. The plants are di- , tetra-, hexa- or octoploid with chromosome numbers of 2n = 10, 14, 16, 18, 28, 30, 42, or 56.

distribution

The Zwenken are mainly found in the temperate zones and in tropical mountains. They occur in the Holarctic, Paleotropic, Neotropic and Capensis. Often they also appear adventurously . They are mesophytic. On the one hand they grow in shady locations, but other species in open locations.

Systematics

The genus Brachypodium was established in 1812 by Ambroise Marie François Joseph Palisot de Beauvois . Brachypodium is derived from the Greek brachys = short, and pous , plural podes = foot. The name refers to the short-stalked spikelets. The genus stands within the sweet grasses in the subfamily Pooideae and alone forms the tribe Brachypodieae. The genus is pretty much at the base of the subfamily Pooideae and is monophyletic.

In Central Europe, the pinnate twins ( Brachypodium pinnatum ), the rock twinks ( Brachypodium rupestre ) and the forest twinks ( Brachypodium sylvaticum ) are native. In Europe and the Mediterranean region, for which the processing in the World Checklist of Selected Plant Families and in Euro + Med Plantbase differ significantly, the following species occur:

  • Brachypodium arbuscula bone , endemic to the Canary Islands of Tenerife , La Gomera and El Hierro .
  • Brachypodium atlanticum Dobignard : Morocco.
  • Brachypodium boissieri Nyman : It occurs only in the south-east Spanish Sierras in the montane zone between 900 and 2050 meters above sea level.
  • Biennial Zwenke ( Brachypodium distachyon (L.) P. Beauv. , Syn .: Trachynia distachya (L.) Link ), native to: Mediterranean area to India, Canary Islands, Cape Verde, Ethiopia, Central Asia, naturalized in South Africa, Australia, North and South America , occurring inconsistently also in Central Europe.
  • Brachypodium glaucovirens (Murb.) Sagorski (Syn .: Brachypodium sylvaticum subsp. Glaucovirens Murb. , Brachypodium firmifolium H. Lindb. ). The home is the Maghreb and the central and eastern Mediterranean area .; it is closely related to Brachypodium sylvaticum .
  • Brachypodium kotschyi Boiss. : The home is southern Turkey.
  • Brachypodium phoenicoides (L.) Roem. & Schult. (Syn .: Brachypodium atlanticum Dobignard ): Homeland: Western and central Mediterranean area, the species is naturalized in Upper Bavaria.
  • Fieder-Zwenke ( Brachypodium pinnatum (L.) P. Beauv. , Syn .: Brachypodium genuense (DC.) Roem. & Schult. ): It occurs from Europe to Mongolia and from the Mediterranean region to Iran and Eritrea.
  • Branched Zwenke ( Brachypodium retusum (Pers.) P. Beauv. ): Widespread from the Mediterranean region to the Caucasus and from Ethiopia to the Arabian Peninsula.
  • Felsen-Zwenke ( Brachypodium rupestre (Host) Roem. & Schult. ), In temperate and meridional Europe and the Middle East. Some authors put the species as a synonym for Brachypodium pinnatum . With two subspecies:
    • Brachypodium rupestre subsp. cespitosum (host) H. Scholz
    • Brachypodium rupestre subsp. rupestre
  • Forest Zwenke ( Brachypodium sylvaticum (Huds.) P. Beauv. ), Widespread in the western Palearctic , also in the Central Asian mountains and in East Asia. With the subspecies:
    • Brachypodium sylvaticum subsp. creticum H. Scholz & Greuter , endemic to the mountains of Crete.
    • Brachypodium sylvaticum subsp. spryginii Tzvelev from Crimea .
    • Brachypodium sylvaticum subsp. sylvaticum (Syn .: Brachypodium gaditanum Talavera )

Other types are:

No longer counted in this genus:

Genetic studies have shown the following cladogram , but not all species were represented:








Brachypodium sylvaticum


   

Brachypodium pinnatum



   

Brachypodium phoenicoides



   

Brachypodium rupestre



   

Brachypodium retusum



   

Brachypodium arbuscula



   

Brachypodium mexicanum



   

Brachypodium distachyon


So at the base is the annual species Brachypodium distachyon , which is often separated into the genus Trachynia . The next branch off is the Mexican Brachypodium mexicanum , a species without rhizomes. The remaining species are the rhizome-bearing perennial species.

Importance to humans

The Zwenken have no economic importance. Brachypodium distachyon is, however, a not insignificant weed and is available as another grass model plant (besides rice ) with the fully sequenced genome.

swell

  • Pilar Catalán, Richard G. Olmstead: Phylogenetic reconstruction of the genus Brachypodium P. Beauv. (Poaceae) from combined sequences of chloroplast ndh F gene and nuclear ITS . In: Plant Systematics and Evolution. Volume 220, No. 1-2, 2000, pp. 1-19, DOI: 10.1007 / BF00985367 .
  • Manfred A. Fischer, Wolfgang Adler, Karl Oswald: Excursion flora for Austria, Liechtenstein and South Tyrol . 2nd, improved and enlarged edition. Province of Upper Austria, Biology Center of the Upper Austrian State Museums, Linz 2005, ISBN 3-85474-140-5 , p. 1179 .
  • Uwe Schippmann: Revision of the European species of the genus Brachypodium Palisot de Beauvois (Poaceae). In: Boissiera. Volume 45, 1991, pp. 1-250.
  • Siegmund Seybold (Ed.): Schmeil-Fitschen interactive . CD-ROM, version 1.1. Quelle & Meyer, Wiebelsheim 2002, ISBN 3-494-01327-6 .
  • L. Watson, MJ Dallwitz: The grass genera of the world: descriptions, illustrations, identification, and information retrieval; including synonyms, morphology, anatomy, physiology, phytochemistry, cytology, classification, pathogens, world and local distribution, and references. Version: November 28, 2005. ( URL ).
  • Walter Erhardt , Erich Götz, Nils Bödeker, Siegmund Seybold: The great pikeperch. Encyclopedia of Plant Names. Volume 2. Types and varieties. Eugen Ulmer, Stuttgart 2008, ISBN 978-3-8001-5406-7 , p. 1252.

Individual evidence

  1. ↑ a b Hans Joachim Conert (Ed.): Illustrated flora of Central Europe . Founded by Gustav Hegi. 3rd, completely revised edition. Volume I. Part 3: Spermatophyta: Angiospermae: Monocotyledones 1 (2). Poaceae (real grasses or sweet grasses) . Parey Buchverlag, Berlin 1998, ISBN 3-8263-2868-X , p. 759 (published 1979–1998).
  2. ^ Manfred A. Fischer, Wolfgang Adler, Karl Oswald: Excursion flora for Austria, Liechtenstein and South Tyrol . 2nd, improved and enlarged edition. Province of Upper Austria, Biology Center of the Upper Austrian State Museums, Linz 2005, ISBN 3-85474-140-5 , p. 1179 .
  3. ^ Ambroise Marie François Joseph Palisot de Beauvois: Essai d'une nouvelle agrostographie, ou, Nouveaux genres des graminées: avec figures représentant les caractères de tous les genres. Self-published, Paris 1812, p. 100 ( digitized versionhttp: //vorlage_digitalisat.test/1%3Dhttp%3A%2F%2Fbiodiversitylibrary.org%2Fpage%2F394179~GB%3D~IA%3D~MDZ%3D%0A~SZ%3D~ double-sided%3D~LT%3D~ PUR% 3D ).
  4. ↑ Helmut Genaust: Etymological dictionary of botanical plant names. 3rd, completely revised and expanded edition. Nikol, Hamburg 2005, ISBN 3-937872-16-7 , p. 105 (reprint from 1996).
  5. ↑ a b c d e Catalán, Olmstead: Phylogenetic reconstruction of the genus Brachypodium , 2000.
  6. ↑ a b c d e f g h i j k l m Rafaël Govaerts (Ed.): Brachypodium. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved January 23, 2020.
  7. ↑ U.Schippmann: Revision of the European species of the genus Brachypodium. In: Boissiera, Vol. 45, 1-249, 1991.
  8. ↑ Hildemar Scholz: On the identity of Brachypodium firmifolium (Poaceae) from Cyprus. In: Willdenowia. Volume 37, No. 1, 2007, pp. 215-220, DOI: 10.3372 / wi.37.37111 .
  9. ↑ a b c d Benito Valdés, Hildemar Scholz; Eckhard von Raab-Straube, Gerald Parolly: Poaceae (pro parte majore). Brachypodium. In: Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity. Berlin 2009.
  10. ↑ a b c Recognized in Euro + Med Plantbase .
  11. ↑ List of species on GRIN
  12. ↑ John P. Vogel, David F. Garvin, Todd C. Mockler, Jeremy Schmutz, Dan Rokhsar, Michael W. Bevan and others: Genome sequencing and analysis of the model grass Brachypodium distachyon . In: Nature . tape 463 , no. 7282 , 2010, p. 763–768 , doi : 10.1038 / nature08747 .

Web links

Commons : Zwenken ( Brachypodium )  - Collection of images, videos and audio files