Brasenia
Encyclopedia
Brasenia is a genus
belonging to the family Cabombaceae
, consisting of one extant species widely distributed in warm temperate and tropical regions of the world. Brasenia is an aquatic perennial plant with floating, peltate leaves and rhizomatous stems. It is identified by its bright green leaves, small purple flowers that bloom from June through September, and a thick mucilage
that covers all of the underwater organs, including the underside of the leaves, stems, and developing buds.
. The flowers have a two-day blooming period. On the first day, the functionally female, or pistillate flower, extends above the surface of the water and exposes the receptive stigmas. The flower then recedes below the water surface and on the following day emerges as a functionally male, or staminate flower. It is elevated higher than on the previous day and the anther-bearing filaments are extended beyond the female carpels. The anthers dehisce, releasing the pollen, and the flower is then withdrawn below the water where the fruit develops. Brasenia spreads rapidly once it is established and is very difficult to control.
(also watershield or water shield).
The genus commemorates the surgeon and Moravian missionary Christoph Brasen (1738-1774), who was the first superintendent of the Moravian mission at Nain
in Labrador
.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
belonging to the family Cabombaceae
Cabombaceae
Cabombaceae is the botanical name of a family of flowering plants. The family has been recognised as distinct by at least some taxonomists and by APG III...
, consisting of one extant species widely distributed in warm temperate and tropical regions of the world. Brasenia is an aquatic perennial plant with floating, peltate leaves and rhizomatous stems. It is identified by its bright green leaves, small purple flowers that bloom from June through September, and a thick mucilage
Mucilage
Mucilage is a thick, gluey substance produced by most plants and some microorganisms. It is a polar glycoprotein and an exopolysaccharide.It occurs in various parts of nearly all classes of plant, usually in relatively small percentages, and is frequently associated with other substances, such as...
that covers all of the underwater organs, including the underside of the leaves, stems, and developing buds.
Characteristics
Brasenia exhibits wind pollinationAnemophily
Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Anemophilous plants may be either gymnosperms or angiosperms ....
. The flowers have a two-day blooming period. On the first day, the functionally female, or pistillate flower, extends above the surface of the water and exposes the receptive stigmas. The flower then recedes below the water surface and on the following day emerges as a functionally male, or staminate flower. It is elevated higher than on the previous day and the anther-bearing filaments are extended beyond the female carpels. The anthers dehisce, releasing the pollen, and the flower is then withdrawn below the water where the fruit develops. Brasenia spreads rapidly once it is established and is very difficult to control.
Uses
Economically, Brasenia is cultivated as a vegetable in China and Japan (where it is known as junsai 蓴菜 ジュンサイ) and the mucilage it produces has been found to have anti-algal and anti-bacterial properties that may be useful as a natural weed control.Name
Brasenia schreberi (syn. B. nymphoides, B. peltata) has the common name water-shieldWater-shield
Water-shield may refer to following aquatic plants:* Brasenia schreberi * Cabomba caroliniana...
(also watershield or water shield).
The genus commemorates the surgeon and Moravian missionary Christoph Brasen (1738-1774), who was the first superintendent of the Moravian mission at Nain
Nain, Newfoundland and Labrador
Nain or Naina is the northernmost town of any size in the Canadian province of Newfoundland and Labrador, located about 370 kilometres by air from Happy Valley-Goose Bay. The town was established as a Moravian mission in 1771 by Jens Haven and other missionaries...
in Labrador
Labrador
Labrador is the distinct, northerly region of the Canadian province of Newfoundland and Labrador. It comprises the mainland portion of the province, separated from the island of Newfoundland by the Strait of Belle Isle...
.