Biology:Wolffia arrhiza
| Wolffia arrhiza | |
|---|---|
| |
| |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Order: | Alismatales |
| Family: | Araceae |
| Genus: | Wolffia |
| Species: | W. arrhiza
|
| Binomial name | |
| Wolffia arrhiza (L.) Horkel ex Wimm.
| |
Wolffia arrhiza is a species of flowering plant known by the common names spotless watermeal and rootless duckweed, belonging to the Araceae, a family rich in water-loving species, such as Arum and Pistia. It is the smallest vascular plant on Earth.[2][3][4] It is native to Europe, Africa, and parts of Asia, and it is present in other parts of the world as a naturalized species.[5][6]
Description
Wolffia arrhiza is an aquatic plant which grows in quiet water bodies such as ponds. The green part of the plant, the frond, is a sphere measuring about 1 mm wide, but with a flat top that floats at the water's surface. It has a few parallel rows of stomata.[3] There is no root. The plant produces a minute flower fully equipped with one stamen and one pistil. It often multiplies by vegetative reproduction, however, with the rounded part budding off into a new individual.[3][7] In cooler conditions the plant becomes dormant and sinks to the bed of the water body to overwinter as a turion.[8] The plant is a mixotroph which can produce its own energy by photosynthesis or absorb it from the environment in the form of dissolved carbon.[4]
Human uses
This tiny plant is a nutritious food. Its green part is about 40% protein by dry weight and its turion is about 40% starch.[9][10] It contains many amino acids important to the human diet, relatively large amounts of dietary minerals and trace elements such as calcium, magnesium, and zinc, and vitamin B12.[10] It has long been used as a cheap food source in Myanmar, Laos, and Thailand, where it is known as khai-nam ("eggs of the water").[11] The plant is prolific in its reproduction, growing in floating mats that can be harvested every 3 to 4 days; it has been shown to double its population in less than four days in vitro.[12]
It is also useful as a form of agricultural and municipal water treatment.[13] It is placed in effluent from black tiger shrimp farms to absorb and metabolize pollutants.[14] The plants grow quickly and take up large amounts of nitrogen and phosphorus from the water.[9] The plants that grow in the wastewater can then be used as feed for animals, such as carp,[15] Nile tilapia,[16] and chickens.[8]
References
- ↑ Lansdown, R.V. (2019). "Wolffia arrhiza". IUCN Red List of Threatened Species 2019: e.T164241A120209232. doi:10.2305/IUCN.UK.2019-2.RLTS.T164241A120209232.en. https://www.iucnredlist.org/species/164241/120209232. Retrieved 30 April 2023.
- ↑ Pietryczuk, A., et al. (2009). The effect of sodium amidotrizoate on the growth and metabolism of Wolffia arrhiza (L.) Wimm. Polish Journal of Environmental Studies 18:5 885-91.
- ↑ 3.0 3.1 3.2 Pan, S. and S. S. C. Chen. (1979). The morphology of Wolffia arrhiza: A scanning electron microscopic study. Bot Bull Academia Sinica 20 89-95.
- ↑ 4.0 4.1 Czerpak, R., et al. (2004). Biochemical activity of auxins in dependence of their structures in Wolffia arrhiza (L.) Wimm. Acta Societatis Botanicorum Poloniae 73:4 269-75.
- ↑ {{citation | mode = cs1 | title = Wolffia arrhiza | work = Germplasm Resources Information Network (GRIN) | url = | publisher = [[Organization:Agricultural Research ServAgricultural Research Service (ARS), United States Department of Agriculture (USDA) | access-date = 2 January 2018 }}
- ↑ "Wolffia arrhiza in Flora of North America @ efloras.org". efloras.org. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200027354.
- ↑ MoBot: Wolffia arrhiza
- ↑ 8.0 8.1 Al Khateeb, N. Duckweed use for sewage treatment and fodder production in Palestine. Water & Environmental Development Organization, Palestine.
- ↑ 9.0 9.1 Fujita, M., et al. (1999). Nutrient removal and starch production through cultivation of Wolffia arrhiza. Journal of Bioscience and Bioengineering 87:2 194-8.
- ↑ 10.0 10.1 Czerpak, R. and I. K. Szamrej. (2003). The effect of β-estradiol and corticosteroids on chlorophylls and carotenoids content in Wolffia arrhiza (L.) Wimm. (Lemnaceae) growing in municipal Bialystok tap water. Polish Journal of Environmental Studies 12:6 677-84.
- ↑ Bhanthumnavin, K. and M. G. McGarry. (1971). Wolffia arrhiza as a possible source of inexpensive protein. Nature (letter) 232:495.
- ↑ National Academy of Sciences. Making aquatic weeds useful: Some perspectives for developing countries. 1976. Page 149.
- ↑ Körner, S., et al. (2003). The capacity of duckweed to treat wastewater. Journal of Environmental Quality 32:5 1583-90.
- ↑ Suppadit, T., et al. (2008). Treatment of effluent from shrimp farms using watermeal (Wolffia arrhiza). ScienceAsia 134 163-8.
- ↑ Naskar, K., et al. (1986). Yield of Wolffia arrhiza (L.) Horkel ex Wimmer from cement cisterns with different sewage concentrations, and its efficacy as a carp feed. Aquaculture 51:3-4 211-16.
- ↑ Chareontesprasit, N. and W. Jiwayam. (2001). ##An evaluation of Wolffia meal (Wolffia arrhiza) in replacing soybean meal in some formulated rations of Nile tilapia. Pakistan Journal of Biological Sciences 4:5 618-20.
External links
Wikidata ☰ Q159100 entry
 |  |
