Ground nettle
| Ground nettle | ||||||||||||
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Ground nettle ( Hydrilla verticillata ) |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Hydrilla | ||||||||||||
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| Scientific name of the species | ||||||||||||
| Hydrilla verticillata | ||||||||||||
| ( Lf ) Royle |
The reason nettle ( Hydrilla verticillata ) is a water plant type from the family of hydrocharitaceae (Hydrocharitaceae). It is the only species in the genus Hydrilla .
description
Hydrilla is an herbaceous perennial plant . It grows submerged (submerged) in fresh water . Here it forms dense stands with shoots up to eight meters long .
The leaves are six to 20 millimeters long and two to four millimeters wide. They are linear with a clear point and clearly serrated edge. You are lively to four to eight to the node ( Nodien ).
This species with separate-sex flowers comes in two forms, a monoecious ( monoecious ) and a dioecious ( diocese ). In the latter there are male and female plants. The latter in particular are common in the USA.
The number of chromosomes of the species is 2n = 16, less often 24.
Occurrence
The ground nettle is native to parts of Asia, Africa and Australia. Their original range extends from Eastern Europe to Asia, from Uganda to northern Zambia and also includes Australia. It is an aggressive neophyte , especially in coastal areas of the USA , which is fought there with herbicides such as Fluridon . The plant, which is sometimes confused with Egeria , Elodea and Lagarosiphon ( false water plague ) species, is used as an aquarium plant.
Multiplication
The reproduction takes place predominantly vegetatively via rhizomes and stolons . The species also reproduces via turions and underground tubers . These tubers can survive for up to four years. Under favorable conditions, a tuber can produce up to 6000 new tubers per square meter. The vegetative reproduction is especially important where only the female plants occur as neophytes.
photosynthesis
Hydrilla verticillata is an optional C 4 plant . In contrast to most of the C 4 plants, however, the leaves are not compartmentalized in mesophyll and bundle sheath cells. The mesophyll of the leaves is made up of two layers of similar cells, the C 4 photosynthesis can take place completely within each of these cells.
literature
- JK Balciunas, MJ Grodowitz, AF Cofrancesco, JF Shearer: Hydrilla . In: R. van Driesche et al .: Biological Control of Invasive Plants in the Eastern United States . USDA Forest Service Publication FHTET-2002-04, 2002, PDF download
Individual evidence
- ^ Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . 8th edition. Page 113. Stuttgart, Verlag Eugen Ulmer, 2001. ISBN 3-8001-3131-5
- ↑ Rafaël Govaerts (ed.): Hydrilla. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved August 22, 2016.
- ↑ Christel Kasselmann : aquarium plants. Ulmer Verlag, Stuttgart 1995; 2nd, revised and expanded edition 1999, ISBN 3-8001-7454-5 , p. 298 f.
Web links
- Ground nettle. In: FloraWeb.de.
- Ground nettle . In: BiolFlor, the database of biological-ecological characteristics of the flora of Germany.
- Distribution in the Netherlands [1] (Dutch)
- Thomas Meyer: Data sheet with identification key and photos at Flora-de: Flora von Deutschland (old name of the website: Flowers in Swabia )
- Detailed description with photos (English)
- Hydrilla in the United States (English)
- Hydrilla in the USA
- Hydrilla verticillata inthe IUCN 2013 Red List of Threatened Species . Posted by: Zhuang, X., 2010. Retrieved January 7, 2014.