Halothamnus

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Halothamnus
Halothamnus subaphyllus ssp. charifii

Halothamnus subaphyllus ssp. charifii

Systematics
Nuclear eudicotyledons
Order : Clove-like (Caryophyllales)
Family : Foxtail family (Amaranthaceae)
Subfamily : Salsoloideae
Tribe : Salsoleae
Genre : Halothamnus
Scientific name
Halothamnus
Jaub. & Spach

Halothamnus is a genus of plants in the foxtail family( Amaranthaceae ). The botanical genus name Halothamnus is derived from the Greek words ἅλς (hals) for salt and θαμνος (thamnos) for shrub and thus means "salt bush"; this can relate to both the salty habitats and the salt accumulation in the plants.

description

Most Halothamnus styles are smaller shrubs and half-shrubs , two types Annuals . The leaves sit alternately and without a basal taper on the stem. They are simple, with entire margins, in cross-section almost pedunculate, concave or flat and slightly fleshy ( succulent ).

The hermaphroditic flowers are inconspicuous and sit individually in the armpit of a supporting sheet (bracts) and two lateral prophylls ( Brakteolen ). Its five non-grown bloom cladding sheets ( tepals ) are colorless in the lower part, above a transverse furrow greenish with a membranous edge. They envelop five stamens , which arise at the base of a bowl-shaped structure (hypogynous discus). Two carpels have become a top permanent ovary grown. The stylus is widened to the base and carries at the top two scars .

The lonely, horizontally flattened fruit remains enclosed by the hardening flower cover ( perianth ). From the transverse furrow on the back of the tepals, membranous, striped wings grow. Below the wings, the tepals thicken and lignify, forming a tube with a flat base, but without growing together. On the underside of the fallen fruit, five pits can be seen in a ring, which are surrounded by a wall. These fruit characteristics are characteristic of the genus Halothamnus .

Pollen from Halothamnus glaucus subsp. tianschanicus

The pollen grains are almost spherical, 18 to 38 µm in diameter, and have about 12 to 29 pores (pantoporat) distributed over the entire surface, as is typical for the goosefoot family. The individual species differ in pollen size and number of pores, with the southern species having the smallest and the northern species the largest pollen grains.

Pollination and fruit spread

In all Halothamnus species, the anthers bloom first, and only after they bloom do the stigmas develop ( proterandry ). In the case of Halothamnus subaphyllus , pollination by insects has been proven ( entomophilia ). The other species have not yet been observed, but there is much to suggest that they are also insect-flowered.

The fruits, enclosed by the hardening flower cover, are spread out by the wind ( anemochory ), whereby the wing discs , which are up to 20 mm in diameter, provide lift.

Photosynthetic pathway

All Halothamnus species have an anatomical leaf structure with a wreath anatomy of the Salsola type. Physiological studies confirmed that photosynthesis takes place via the C 4 metabolic pathway ( C4 plants ).

Distribution area of ​​the genus Halothamnus

Occurrence

The distribution area of ​​the genus Halothamnus extends in a north-south direction from Kazakhstan to Somalia , and in a west-east direction from the Sinai Peninsula to Djungaria in China. The highlands of Iran and Afghanistan as well as Central Asia (Uzbekistan, Turkmenistan) are particularly rich in species .

All Halothamnus species grow in dry locations in semi-deserts and deserts , from the plains to altitudes of around 2800 meters in the mountains. They colonize stony, loamy or sandy soil , and many halothamnus species also tolerate salty or gypsum-containing soil.

use

Halothamnus iranicus

Some Halothamnus species are important forage crops for camels, sheep and goats, which is why they are grown for the recultivation of pastureland, for example Halothamnus subaphyllus , Halothamnus auriculus and Halothamnus glaucus . Halothamnus subaphyllus is also used to fortify sandy areas and to extract the medicinally used alkaloid salsolin . Halothamnus somalensis is used as a medicinal plant against parasitic worms . Before the introduction of potash mining, alkalis were extracted from Halothamnus subaphyllus and Halothamnus glaucus for soap-making .

Systematics

The first illustration of a Halothamnus plant by JC Buxbaum as "Kali fruticosum spicatum" in 1728 shows Halothamnus glaucus

The genus Halothamnus was established in 1845 by Hippolyte François Jaubert and Édouard Spach in Illustrationes Plantarum Orientalium , 2, 50, plate 136. As Lectotypusart in 1874 Halothamnus bottae Jaub. & Spach set. Synonyms for Halothamnus Jaub. & Spach are Aellenia (Ulbr.) Emend. Aellen and Salsola L. sect. Sphragidanthus Ilyin .

The genus Halothamnus is related to the genus brine ( Salsola ) and belongs to the subtribe Sodinae from the tribe Salsoleae in the subfamily Salsoloideae within the family Amaranthaceae . Phylogenetic studies have shown that the genus is monophyletic .

The genus Halothamnus is divided into two sections by Kothe-Heinrich and contains 21 species (distribution information according to Kothe-Heinrich 1993):

literature

  • Gabriele Kothe-Heinrich: Revision of the genus Halothamnus (Chenopodiaceae) . Bibliotheca Botanica Vol. 143, Schweizerbart, Stuttgart 1993. ISBN 978-3-510-48014-2
  • Gabriele Kothe-Heinrich: Halothamnus , In: Karl Heinz Rechinger et al. (Edit.): Flora Iranica , Vol. 172, Chenopodiaceae , Akad. Druck, Graz 1997: Pages 255-289. ISBN 3-201-00728-5

Individual evidence

  1. ^ Gabriele Kothe-Heinrich: Revision of the genus Halothamnus (Chenopodiaceae) . Bibliotheca Botanica Vol. 143, Schweizerbart, Stuttgart 1993, ISBN 978-3-510-48014-2 , pp. 13-14 and pp. 174-176. (Pollen)
  2. ↑ MM Ilyin: K biologii Anabasis aphylla L. , In: Sovetsk. Bot. , Vol. 4, 1937, pp. 69-76.
  3. ↑ A. Shomer-Ilan, A. Nissenbaum & Y. Waisel: Photosynthetic pathways and the ecological distribution of the Chenopodiaceae in Israel , In: Oecol. (Berlin) , 48, 198, pp. 244-2481.
  4. ↑ K. Winter: C4 plants of high biomass in arid regions of Asia. Occurrence of C4 photosynthesis in Chenopodiaceae and Polygonaceae from the Middle East and USSR , In: Oecol. (Berlin) , 48, 1981, pp. 100-106.
  5. ↑ OV Zalenskij & T. Glagoleva: Pathway of carbon metabolism in halophytic desert species from Chenopodiaceae , In: Photosynthetica (Prague) , 15 (2), 1981, pp 244-255.
  6. ↑ a b G. K. Kinzikaeva: Aellenia , In: PN Občinnikov (ed.): Flora Tadžikskoj SSR , 3, Leningrad: Nauka, 1968, pp. 419-425.
  7. ↑ [1] (PDF; 1.6 MB) Combating Desertification - Traditional Knowledge and Modern Technology for the Sustainable Management of Dryland Ecosystems , UNESCO-MAB Drylands Series No. 4, 2005, p. 156.
  8. ↑ AF Gammerman et al .: Lekarstvenny rasteniâ SSSR, rastitelnoe syr'e SSSR. , In: Moskva, Leningrad: Izd. Akad. Nauk SSSR , 1957.
  9. ↑ SE Zemlinskij: Lekarstvennye rasteniâ SSSR. , In: Moskva: Medgiz , 1958.
  10. ↑ F. & M. Dawo Tibbo: anthelmintic effect of Halothamnus somalensis in Arsi-Bale goats . In: Livestock Research for Rural Development . Volume 17, Article # 68, 2005.
  11. ↑ P. Aellen: Chenopodiaceae , In: G. Hegi (Ed .: KH Rechinger): Illustrierte Flora von Mitteleuropa , 2nd edition, 3 (2), Parey, Berlin / Hamburg 1961 pp. 533–747.
  12. ↑ Halothamnus at Tropicos.org. Missouri Botanical Garden, St. Louis
  13. ↑ Hossein Akhani, Gerald Edwards, Eric H. Roalson: Diversification Of The Old World Salsoleae SL (Chenopodiaceae): Molecular Phylogenetic Analysis Of Nuclear And Chloroplast Data Sets And A Revised Classification , In: International Journal of Plant Sciences , 168 (6), 2007, pp. 931-956.

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