Dandelion
A flowering dandelion.
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Asterales Family: Asteraceae Tribe: Cichorieae Genus: Taraxacum Cass.
Species
See text

The common name Dandelion is given to members of the genus Taraxacum, a large genus of flowering plants in the family Asteraceae. Plants are living Organisms belonging to the kingdom Plantae. The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group Dicotyledons, or "dicots", is a name for a group of Flowering plants whose Seed typically has two embryonic leaves or Cotyledons There The Asterales are an order of Dicotyledonous Flowering plants which include the composite family Asteraceae ( Sunflowers daisies The family Asteraceae or Compositae (known as the aster, daisy, or sunflower family) is the largest family of Flowering Cichorieae (sometimes Lactuceae) is a tribe of plants in the family Asteraceae that includes 100 genera and more than 1600 species Count Alexandre Henri Gabriel de Cassini (1781-1832 was a French Botanist and naturalist, who specialised in the sunflower family ( Asteraceae) (then known A genus (plural genera from Γένος Latin genus "descent family type gender" is a low-level Taxonomic The flowering plants or angiosperms ( Angiospermae or Magnoliophyta) are the most widespread group The family Asteraceae or Compositae (known as the aster, daisy, or sunflower family) is the largest family of Flowering In the Asteraceae (formerly Compositae) the "flowers" are morphologically a composite flower head consisting of many tiny flowers called florets. The term morphology in Biology refers to the outward appearance ( Shape, Structure, Colour, Pattern) of an Organism Dandelions are native to Europe and Asia and have been widely introduced elsewhere. Many Taraxacum species produce seeds asexually by apomixis, where the seeds are produced without pollination, resulting in offspring that are genetically identical to the parent plant. Asexuality is a Sexual orientation that describes individuals who do not experience Sexual attraction. Pollination in angiosperms and Gymnosperms is the process that transfers pollen grains, which contain the male Gametes (sperm to where the female ^[1]

Description

A dandelion clock.

Dandelions are tap-rooted biennial or perennial herbaceous plants, native to temperate areas of the Northern Hemisphere of the Old World. A Plant 's taproot is a straight tapering Root that grows vertically down A biennial plant is a flowering Plant that takes two years to complete its lifecycle. A perennial plant or perennial ( Latin per, "through" annus, "year" is a Plant that lives for more than A herbaceous plant (or in botanical use a Herb) is a Plant that has leaves and stems that die down at the end of Northern Hemisphere is the half of a Planet that is North of the Equator —the word hemisphere literally means 'half ball' The Old World consists of those parts of Earth known to Europeans Asians and Africans in the 15th century They are commonly known as weeds or ruderals. A ruderal species is a Plant Species that is first to colonise disturbed lands The genus is taxonomically complex, with some botanists dividing the group into numerous macrospecies, and many more microspecies: approximately 235 apomictic and polyploidic microspecies have been recorded in Great Britain and Ireland^[2]. Taxonomy is the practice and science of classification The word comes from the Greek, taxis (meaning 'order' 'arrangement' and, nomos Botany, plant science(s, phytology, or plant biology is a branch of Biology and is the scientific study of plant Life Polyploidy occurs in cells and Organisms when there are more than two homologous sets of Chromosomes. See also Kingdom of Great Britain Great Britain (Breatainn Mhòr Prydain Fawr Breten Veur Graet Breetain is the larger of the two main islands Ireland (pronounced /ˈaɾlənd/ Éire) is the third largest island in Europe, and the twentieth-largest island in the world Some botanists take a much narrower view and only accept a total of about 60 species. ^[3]

The leaves are 5–25 cm long, simple and basal, entire or lobed, forming a rosette above the central taproot. As the leaves grow outward they push down the surrounding vegetation, such as grass in a lawn, which kills those plants by cutting off their access to sunlight. A bright yellow flower head, which is open in the daytime but closes at night, is borne singly on a hollow stem (scape) which rises 4–30 cm above the leaves and exudes a milky sap (latex) when broken. An inflorescence is a group or cluster of Flowers arranged on a stem that is composed of a main Branch or a complicated arrangement of branches LaTeX (ˈleɪtɛ A rosette may produce several flowering stems at a time. The flower head is 2–5 cm in diameter and consists entirely of ray florets. A flower, also known as a bloom or Blossom, is the reproductive structure found in Flowering plants (plants of the division Magnoliophyta, also The flower head matures into a spherical "clock" (also known as a "wishie") containing many single-seeded fruits (achenes). An achene is a type of simple dry Fruit produced by many species of Flowering plants Achenes are "monocarpellate" (formed from one Carpel Each achene is attached to a pappus of fine hairs, which enable wind-aided dispersal over long distances. In a composite Flower, Pappus is the part of individual disk and ray flowers that surrounds the base in the same manner as the calyx does in a non-compound

Dandelions are used as food plants by the larvae of some species of Lepidoptera (butterflies and moths). A larva ( Latin; plural larvae) is a juvenile form of Animal with indirect development, undergoing Metamorphosis (for example Lepidoptera is an order of Insect that includes Moths and butterflies. A butterfly is an Insect of the order Lepidoptera. Like all Lepidoptera butterflies are notable for their unusual life cycle with a See List of Lepidoptera that feed on dandelions. Dandelions ( Taraxacum spp are used as food plants by the Larvae of a number of Lepidoptera species including Arctiidae

A dandelion flower head.

Away from their native regions, dandelions have become established in the Americas, Australia, and New Zealand, and are now common throughout all temperate regions. The Americas are the lands of the Western hemisphere or New World, consisting of the Continents of North America and South America For a topic outline on this subject see List of basic Australia topics. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island

History

Dandelions evolved about thirty million years ago in Eurasia[1].

They have been used by humans for food and herbalism for much of recorded history.

Origin of the name

The English name dandelion is a corruption of the French dent de lion^[4] meaning lion's tooth, referring to the coarsely-toothed leaves. The lion ( Panthera leo) is a member of the family Felidae and one of four Big cats in the Genus Panthera. The names of the plant have the same meaning in several other European languages, such as Italian dente di leone, Spanish diente de león, Portuguese dente-de-leão, Norwegian Løvetann, and German Löwenzahn. Italian ( or lingua italiana) is a Romance language spoken by about 63 million people as a First language, primarily in Italy. Portuguese ( or língua portuguesa) is a Romance language that originated in what is now Galicia (Spain and northern Portugal. Norwegian ( norsk) is a North Germanic Language spoken primarily in Norway, where it is an official language The German language (de ''Deutsch'') is a West Germanic language and one of the world's major languages.
In modern French the plant is named pissenlit, which means "urinate in bed", apparently referring to its diuretic properties. French ( français,) is a Romance language spoken around the world by 118 million people as a native language and by about 180 to 260 million people A diuretic is any Drug that elevates the rate of urination ( Diuresis) Likewise, "pissabeds" is an English folkname for this plant, piscialletto in Italian and in Spanish it is known as the meacamas. Also, in the dialect of Veneto, Italy, it is known as pisacan, which translates to "dog pisses", referring to how common they are found at the side of pavements (source: Giulia Zanetti, native of Veneto), and in the dialect of Novara, Italy, it is known as soffione, which translates to "blowing", and refers to the habit of blowing the seeds from the stalk (source: Silvia Paracchini, native of Novara). Likewise, in Polish it is called "dmuchawiec" which comes from "dmuchać", "to blow" when in its seed state. Polish ( język polski, polszczyzna) is the Official language of Poland. Whilst in flower form the Poles know it as "Mlecz" a word derived from milk due to its milky sap.
In Turkish the dandelion is called karahindiba meaning "black endive". Turkish ( tr Türkçe IPA) is a language spoken by over 63 million people worldwide making it the most commonly spoken of the Turkic languages.
Hungarian names are kutyatej ("dog milk", referring to the white sap found in the stem) and gyermekláncfű ("child's chain grass", referring to the habit of children to pick dandelions, remove the flowers, and make links out of the stems by "plugging" the narrow top end of the stem into the wider bottom end). Hungarian ( magyar nyelv) is a Uralic language (more specifically a Ugric language) unrelated to most other languages in Europe.
Lithuanian name kiaulpienė can be translated as "sow Sonchus" (because plant Sonchus that has white sap also in Lithuanian is pienė (from pienas "milk)) or "sow milk". Lithuanian ( lietuvių kalba) is the official state language of Lithuania and is recognised as one of the official languages of the European Union. Sow thistles (less commonly hare thistles or hare lettuces) are annual herbs in the genus Sonchus, after their Ancient Greece In Finnish it is called 'voikukka' ("butter flower") referring to its buttery colour. Finnish ( or suomen kieli) is the language spoken by the majority of the population in Finland (92% As of 2006) and by ethnic Finns outside In Swedish it is called 'maskros' ("worm rose"), likely referring to its low status (being mostly considered a weed) despite a fairly pleasant appearance. Swedish ( is a North Germanic language spoken by more than nine million people predominantly in Sweden and parts of Finland, especially along the

Seeds

A microscopic view of a pappus from a dandelion clock. In a composite Flower, Pappus is the part of individual disk and ray flowers that surrounds the base in the same manner as the calyx does in a non-compound

The flower head is surrounded by bracts (sometimes mistakenly called sepals) in two series. In Botany, a bract is a modified or specialized Leaf. Bracts are ordinarily associated with reproductive structures (subtending Flowers Inflorescence A sepal (from Latin separatus "separate" + petalum "petal" is a part of the flower of Angiosperms or flower plants The inner bracts are erect until the seeds mature, then flex down to allow the seeds to disperse; the outer bracts are always reflexed downward. In Botany, a bract is a modified or specialized Leaf. Bracts are ordinarily associated with reproductive structures (subtending Flowers Inflorescence Some species drop the "parachute" (called a pappus, modified sepals) from the achenes. Between the pappus and the achene, there is a stalk called a beak, which elongates as the fruit matures. The beak breaks off from the achene quite easily. After pollination, the dandelion flower dries out for about 1-2 days and then the seed-bearing parachutes expand and lift out of the dried flower head. The dried part of the flower drops off and the parachute ball opens into a full sphere. The parachute drops off when the seed strikes an obstacle. Often dandelions can be observed growing in a crevice near a wall, because the blowing fruits hit the wall and the feathery pappi drop off, sending the dandelion seeds to the base of the obstacle where they germinate. After the seed is released, the parachutes lose their feathered structure and take on a fuzzy, cotton-like appearance, often called "dandelion snow. " While it was probably not developed evolutionarily, Dandelions seeds are often dispersed by young children, who often blow on or kick the clock.

Seed development and genetics

A microscopic view of a dandelion clock showing the pericarp and the achenes. A Fruit in Botany refers to a mature ovary. In fleshy fruits the outer often edible layer is the pericarp, which is the tissue that develops An achene is a type of simple dry Fruit produced by many species of Flowering plants Achenes are "monocarpellate" (formed from one Carpel

As previously mentioned, the taxonomical situation of the genus is quite complex, mainly because many dandelions are genetically triploid. Polyploidy occurs in cells and Organisms when there are more than two homologous sets of Chromosomes. An odd number of chromosomes usually is associated with sterility, but dandelions with this karyotype can reproduce without fertilization, by a process called apomixis. A chromosome is an organized structure of DNA and Protein that is found in cells. Female infertility|Male infertility Infertility primarily refers to the biological inability of a Man or a Woman to contribute to conception. A karyotype is the characteristic Chromosome complement of a Eukaryote Species. For soil improvement see Fertilization (soil. ^[5] In these individuals flowers are inefficient vestigial structures, although they may still produce a small percentage of fertile pollen, keeping some genetic contact with sexual individuals. A flower, also known as a bloom or Blossom, is the reproductive structure found in Flowering plants (plants of the division Magnoliophyta, also Vestigiality describes homologous characters of Organisms which have lost all or most of their original function in a species through Pollen is a fine to coarse powder consisting of microgametophytes ( pollen grains) which produce the male Gametes (sperm cells of Diploid dandelions develop seeds after cross-pollination and are outcrossing, or self-incompatible. "Haplo" redirects here For the fictional character see The Death Gate Cycle. Pollination in angiosperms and Gymnosperms is the process that transfers pollen grains, which contain the male Gametes (sperm to where the female Outcrossing is the practice of introducing unrelated genetic material into a breeding line In most zones of southern Europe and Asia, dandelion populations are sexual or mixed sexual-apomictic, while in northern countries only triploid and tetraploid apomicts are present, as is in the zones where it is not native. Polyploidy occurs in cells and Organisms when there are more than two homologous sets of Chromosomes. This seems to be linked to higher temperatures, survival of pre-glacial populations and human impact, but the subject is still being studied.

There are usually 54 to 172 seeds produced per head, but a single plant can produce more than 2000 seeds a year. It has been estimated that more than 97 000 000 seeds/hectare could be produced every year by a dense stand of dandelions. Explanation The hectare is commonly used in most countries around the world especially in domains concerned with land planning and management such as Agriculture,

Uses

The dandelion's taproot, on left in this drawing, makes this plant very difficult to uproot; the top of the plant breaks away, but the root stays in the ground and can sprout again. A Plant 's taproot is a straight tapering Root that grows vertically down

See also: Medicinal properties of dandelion

While the dandelion is considered a weed by most gardeners and lawn owners, the plant does have several culinary uses, and the specific name officinalis refers to its value as a medicinal herb. Dandelions may have Medicinal properties. Definition The common Dandelion, taraxacum officinale, is a Weed that is WEED (1390 AM) is a Radio station broadcasting a Spanish format Culinary art is the Art of Cooking. The word "culinary" is defined as something related to or connected with cooking or Kitchens A culinarian A(n herb (ˈhɝb or /ˈɝb/ see pronunciation differences) is a plant that is valued for qualities such as medicinal properties flavor scent or the like Dandelions are grown commercially on a small scale as a leaf vegetable. Leaf vegetables, also called potherbs, greens, or leafy greens, are plant leaves eaten as a Vegetable, sometimes accompanied The leaves (called dandelion greens) can be eaten cooked or raw in various forms, such as in soup or salad. Soup is a Food that is made by combining ingredients such as Meat and Vegetables in stock or hot/boiling Water, until the flavor Salad is a mixture of cold foods usually including vegetables and/or fruits often with a dressing occasionally nuts or Croutons, and sometimes with the addition of They are probably closest in character to mustard greens. For the prepared condiment see Mustard (condiment. For other uses of the term "mustard" see Mustard. Usually the young leaves and unopened buds are eaten raw in salads, while older leaves are cooked. Raw leaves have a slightly bitter taste. Dandelion salad is often accompanied with hard boiled eggs. An egg is a round or oval body laid by the female of many animals consisting of an Ovum surrounded by layers of Membranes and an outer casing which acts to nourish The leaves are high in vitamin A, vitamin C and iron, carrying more iron and calcium than spinach. Vitamin A refers to a family of similarly shaped molecules the Retinoids. Vitamin C or L-ascorbate is an Essential nutrient for a large number of higher primate species a small number of other Mammalian Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 Spinach ( Spinacia oleracea) is a Flowering plant in the family of Amaranthaceae. ^[6]

Dandelion flowers can be used to make dandelion wine, for which there are many recipes. Wine is an Alcoholic beverage made from the fermentation of Grape juice ^[7] It has also been used in a saison ale called Pissenlit (literally "wet the bed" in French) made by Brasserie Fantôme in Belgium. Saison ( French, "season" is the name originally given to refreshing low-alcohol Pale ales brewed seasonally in farmhouses in Wallonia, the French-speaking Ale is a type of Beer brewed from Malted Barley using a top-fermenting Brewers' yeast. General This small and idiosyncratic craft brewery is located in the part of Wallonia known as the Ardennes, a French-speaking area of south-eastern Belgium The Kingdom of Belgium is a Country in northwest Europe. It is a founding member of the European Union and hosts its headquarters as well as those Another recipe using the plant is dandelion flower jam. Ground roasted dandelion root can be used as a coffee substitute. CoFFEE is an Open source Software for computer supported collaborative learning (CSCL in a digital classroom Dandelion root is a registered drug in Canada, sold principally as a diuretic. Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page A diuretic is any Drug that elevates the rate of urination ( Diuresis) A leaf decoction can be drunk to "purify the blood", for the treatment of anemia, jaundice, and also for nervousness. A decoction is a method of extraction of Herbal or plant material which includes but is not limited to Stems roots bark and Rhizomes Some Drunk before meals, dandelion root coffee is claimed to stimulate digestive functions and function as a liver tonic. "Dandelion and Burdock" is a soft drink that has long been popular in the United Kingdom with authentic recipes sold by health food shops. Dandelion and burdock is a traditional British Soft drink. Traditionally it is made from fermented Dandelion ( Taraxacum officinale) and The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located It is unclear whether cheaper supermarket versions actually contain extracts of either plant.

The milky latex has been used as a mosquito repellent;^[8]the milk has also been used to treat warts, as a folk remedy. ^[9]

Yellow or green dye colours can be obtained from the flowers but little colour can be obtained from the roots of the plant. ^[10]

A plate of sauteed dandelion greens, with Wehani rice

Antioxidant properties

Dandelion contains luteolin, an antioxidant, and has demonstrated antioxidant properties without cytotoxicity. Wehani rice is a variety of aromatic Brown rice developed in the late 20th century by Lundberg Family Farms of Richvale, California, United An antioxidant is a Molecule capable of slowing or preventing the oxidation of other molecules Cytotoxicity is the quality of being toxic to cells Examples of toxic agents are a Chemical substance, an Immune cell or some types of Venom ^[11][12]

Caffeic acid and carcinogenicity

Caffeic acid is a secondary plant metabolite produced in dandelion, yarrow, horsetail and whitethorn. Caffeic acid, C 9 H 8 O 4 is a naturally occurring Phenolic compound (formerly called a carbolic Achillea millefolium or Yarrow (other common names Common Yarrow Gordaldo, Nosebleed plant, Old Man's Pepper, Sanguinary Equisetum is a genus of Vascular plants that reproduce by spores rather than seeds Despite its name, it is unrelated to caffeine. Caffeine is a bitter white crystalline Xanthine Alkaloid that acts as a Psychoactive Stimulant Drug and a mild Diuretic Recent studies have revealed this acid may be carcinogenic. The term carcinogen refers to any substance Radionuclide or radiation that is an agent directly involved in the promotion of Cancer or in the fatation of its propagation Caffeic acid was tested for carcinogenicity by oral administration in mice, it produced renal cell adenomas in females, and a high incidence of renal tubular cell hyperplasia in animals of each sex. An adenoma is a collection of growths (-oma of glandular origin Hyperplasia (or "hypergenesis" is a general term referring to the proliferation of cells within an organ or tissue beyond that which is ordinarily seen in e ^[13] However, more recent research shows that bacteria present in the rodents' intestines may alter the formation of metabolites of caffeic acid. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind" - specifically the study of their small-molecule metabolite ^[14][15] There have been no known ill-effects of caffeic acid in humans.

Bees

Dandelions are important plants for bees. Not only is their Template:Phenology used as an indicator that the honey bee season is starting, but they are also an important source of nectar and pollen early in the season.

False dandelions

Macro photo of dandelion seed dispersal. Macro photography is close-up Photography; the classical definition is that the Image projected on the "film plane" (i

Dandelions are so similar to catsears (Hypochaeris) that catsears are also known as "false dandelions. Catsear ( Hypochaeris radicata) also known as cat's ear or false dandelion, is a perennial, low-lying edible Herb often found " Both plants carry similar flowers which form into windborne seeds. However, dandelion flowers are borne singly on unbranched, hairless and leafless, hollow stems, while catsear flowering stems are branched, solid and carry bracts. Both plants have a basal rosette of leaves and a central taproot. However, the leaves of dandelions are smooth or glabrous, whereas those of catsears are coarsely hairy.

Other plants with superficially similar flowers include hawkweeds (Hieracium) and hawksbeards (Crepis). Hawkweed refers to any species in the very large genus Hieracium and its segregate genus Pilosella, in the Sunflower family (Asteraceae Crepis is a Genus of about 200 annual and perennial flowering plants found in the Family Asteraceae resembling These are both readily distinguished by their branched flowering stems which are usually hairy and bear leaves.

Selected species

• Taraxacum albidum, a white-flowering Japanese dandelion. For a topic outline on this subject see List of basic Japan topics.
• Taraxacum californicum, the endangered California dandelion
• Taraxacum officinale (syn. Taraxacum californicum, also known as the California dandelion, is an Endangered species of Dandelion endemic to the San Bernardino Taraxacum officinale, commonly called Dandelion, is a herbaceous perennial plant of the family Asteraceae (Compositae T. officinale subsp. vulgare), Common Dandelion. Found in many forms.
• Taraxacum japonicum, Japanese dandelion. No ring of smallish, downward-turned leaves under the flowerhead.
• Taraxacum laevigatum (syn. T. erythrospermum), Red-seeded Dandelion; achenes reddish brown and leaves deeply cut throughout length. Inner bracts' tips are hooded.

References

External links

• Everitt, J. H. ; Lonard, R. L. , Little, C. R. (2007). Weeds in South Texas and Northern Mexico. Lubbock: Texas Tech University Press.   ISBN 0-89672-614-2
• Richards, A. J. 1972. The Taraxacum flora of the British Isles. Watsonia 9 (supplement): 1-141.
• Gail, Peter. The Dandelion Celebration: A Guide to Unexpected Cuisine. Cleveland, Ohio: Goosefoot Acres Press, 1994. ISBN 1-879863-51-0.
• Making Dandelions Palatable by John Kallas of Wild Food Adventures
• How to cook dandelions ~ at Wikibooks
• Dandelion Syrup - step-by-step illustrated recipe in English
• How to Get Rid of Dandelions
• How to Grow Dandelions
• Dandelion Poetry, Folklore, Literature, and Pictures
• Dandelion at Plants For A Future
• a university of Wisconsin article on dandelions
• Timelapse video of dandelions opening
• SpringerLink. Chun Hu and David D. Kitts. Food, Nutrition and Health, Faculty of Agricultural Sciences, University of British Columbia, Vancouver, BC, Canada. October 2004. Luteolin and luteolin-7-O-glucoside from dandelion flower suppress iNOS and COX-2 in RAW264. 7 cells. Springer Netherlands. 245:1-2(107-113).

See also

• List of beneficial weeds
• List of companion plants