Daucus carota

Wild carrot
The umbel of a wild carrot
Scientific classification
Kingdom:	Plantae
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Apiales
Family:	Apiaceae
Genus:	Daucus
Species:	D. carota
Binomial name
Daucus carota L.
Synonyms[1]
Carota sylvestris (Mill.) Rupr. Caucalis carnosa Roth Caucalis carota (L.) Crantz Caucalis daucus Crantz Daucus alatus Poir. Daucus allionii Link Daucus australis Kotov nom. illeg. Daucus blanchei Reut. Daucus brevicaulis Raf. Daucus communis Rouy & E.G.Camus Daucus dentatus Bertol. Daucus esculentus Salisb. Daucus exiguus Steud. Daucus glaber Opiz ex Čelak. Daucus heterophylus Raf. Daucus kotovii M.Hiroe Daucus levis Raf. Daucus marcidus Timb.-Lagr. Daucus maritimus With. nom. illeg. Daucus montanus Schmidt ex Nyman Daucus neglectus Lowe Daucus nudicaulis Raf. Daucus officinalis Gueldenst. ex Ledeb. Daucus polygamus Jacq. ex Nyman nom. inval. Daucus scariosus Raf. Daucus sciadophylus Raf. Daucus strigosus Raf. Daucus sylvestris Mill. Daucus vulgaris Garsault nom. inval. Daucus vulgaris Neck.

Daucus carota, whose common names include wild carrot, bird's nest, bishop's lace, and Queen Anne's lace (North America), is a white, flowering plant in the family Apiaceae, native to temperate regions of Europe and southwest Asia, and naturalized to North America and Australia.

Domesticated carrots are cultivars of a subspecies, Daucus carota subsp. sativus.

Description

Queen Anns Lace -- Daucus carota

Fruit cluster containing oval fruits with hooked spines

The wild carrot is a herbaceous, somewhat variable biennial plant that grows between 30 and 60 cm (1 and 2 ft) tall, and is roughly hairy, with a stiff, solid stem. The leaves are tripinnate, finely divided and lacy, and overall triangular in shape. The leaves are bristly and alternate in a pinnate pattern that separates into thin segments. The flowers are small and dull white, clustered in flat, dense umbels. The umbels are terminal and approximately 3–4 inches (8–10 cm) wide.^[2] They may be pink in bud and may have a reddish or purple^[3] flower in the centre of the umbel. The lower bracts are three-forked or pinnate, which distinguishes the plant from other white-flowered umbellifers. As the seeds develop, the umbel curls up at the edges, becomes more congested, and develops a concave surface. The fruits are oval and flattened, with short styles and hooked spines.^[4] The fruit is small, dry and bumpy with protective hairs surrounding it.^[2] The fruit of Daucus carota has 2 mericarp, or bicarpellate. The endosperm of the fruit grows before the embryo.^[5] The dried umbels detach from the plant, becoming tumbleweeds.^[6] The function of the tiny red flower, coloured by anthocyanin, is to attract insects. Wild carrot blooms in summer and fall. It thrives best in sun to partial shade. Daucus carota is commonly found along roadsides and in unused fields.^[2]

Similar in appearance to the deadly poison hemlock, D. carota is distinguished by a mix of tripinnate leaves, fine hairs on its solid green stems and on its leaves, a root that smells like carrots, and occasionally a single dark red flower in the center of the umbel.^[7][8]

Uses

Like the cultivated carrot, the D. carota root is edible while young, but it quickly becomes too woody to consume. The flowers are sometimes battered and fried. The leaves are also edible except in large quantities.^[2]

Extra caution should be used when collecting D. carota because it bears a close resemblance to poison hemlock. In addition, the leaves of the wild carrot may cause phytophotodermatitis,^[9] so caution should also be used when handling the plant. It has been used as a method of contraception and an abortifacient for centuries.^[10]

If used as a dyestuff, the flowers give a creamy, off-white color.

D. carota, when freshly cut, will draw or change color depending on the color of the water in which it is held. This effect is only visible on the "head" or flower of the plant. Carnations also exhibit this effect. This occurrence is a popular science demonstration in primary grade school.

Beneficial weed

This beneficial weed can be used as a companion plant to crops. Like most members of the umbellifer family, it attracts wasps to its small flowers in its native land; however, where it has been introduced, it attracts very few wasps. This species is also documented to boost tomato plant production when kept nearby, and it can provide a microclimate of cooler, moister air for lettuce, when intercropped with it.^[11] However, the states of Iowa, Ohio, Michigan and Washington have listed it as a noxious weed,^[12] and it is considered a serious pest in pastures. It persists in the soil seed bank for two to five years.^[13]

Taste

Several different factors can cause the root of a carrot to have abnormal metabolites (found to be caused by the 6-methoxymellin compound) that can cause a bitter taste in the roots. An example of this would be that when in the presence of apples, carrots also have a more bitter taste. Also, ethylene can easily produce stress, causing the carrots abnormal, bitter taste.^[14]

Queen Anne's lace

D. carota was introduced and naturalized in North America, where it is often known as "Queen Anne's lace". Both Anne, Queen of Great Britain, and her great grandmother, Anne of Denmark, are taken to be the Queen Anne for which the plant is named.^[15] It is so called because the flower resembles lace; the red flower in the center is thought to represent a blood droplet where Queen Anne pricked herself with a needle when she was making the lace.

History through artwork

The history of Daucus carota and its cultivation in different parts of the world can be traced back through historical texts and artwork. Paintings from the 16th and 17th century, for example, that are of maids in a market or farmer's most recent crop scan be of great information on carrot's history. Studying these paintings can show how and when different subspecies developed. Yellow or red roots were found to be cultivated in Turkey, North Africa, and Spain. Anthocyanins were also shown in the paintings. If has also been found that orange colored roots were cultivated in 17th century Netherlands.^[16]

Taxonomy

The carrot was first officially described by Carl Linnaeus in his 1753 work Species Plantarum.^[17]

Subspecies

"As far as known cultivated forms have only been derived from the species Daucus carota L. Classification of the wild forms of this species is difficult because of a more or less continuous variation in the material. But THELLUNG (20) classifies them in two groups eucarota and gummiferi) each consisting of five main types (subspecies). Plants of the group eucarota are mostly annuals or biennials; this group comprises the subspecies maritimus, carota, maior, sativus (cultivated carrot), and maximus. Plants of the group gummiferi are often perennials but they die after flowering once; this group includes the subspecies commutatis, hispanicus, fontanesii, bocconei and gummifer. Daucus carota subsp. carota is the commonest wild carrot of Europe and S. W. Asia."^[18]

Both domestic and wild carrot are from the same species, Daucus carota L. There are several subspecies of Daucus carota that have evolved to different climates and atmospheres. Two examples of these subspecies are specifically form the Netherlands. D. carota subsp. sativus has roots that can be a wide range of colors. It has a thicker root and sweeter taste. The whorl of barbs above the spine on the vallecular ridges of the mericarp of D. carota subsp. sativus mature very well. D. carota subsp. carota has white roots that do not vary in color and, unlike D. carota subsp. sativus, have a thin root, bitter taste and are not edible. The middle umbellet of D. carota subsp. carota is not well developed (unlike D. carota subsp. sativus) and the color of the flower can vary from red to deep purple.^[19]

Toxicity

In Daucus carota, the amount of toxin overall is small, though it has been known to cause a slight intoxication to grazing large mammals, like cattle and horses, when ingested.^[20] If too much of the plant is consumed, the wildflower can be dangerously toxic to humans.^[2] "Daucus [carota] has been reported to contain acetone, asarone, choline, ethanol, formic acid, HCN, isobutyric acid, limonene, malic acid, maltose, oxalic acid, palmitic acid, pyrrolidine, and quinic acid."^[21] When in contact with wet Daucus carota, skin irritation and vesication may occur. The cell sap of Daucus carota can also cause skin irritation.

Carotoxin

The compound carotoxin is naturally found in Daucus carota. It is found to be toxic to mice and Daphnia Magna.^[20]

Diseases

Black Root Rot

Black root rot of carrot is caused by a pathogenic fungus Chalara elegans (Thielaviopsis basicola). The fungus infects several types of crops including carrots. C. elegans can infect carrots in all stages of growth, thriving in humidity and warm temperatures. When infected, the carrot starts to develop black markings on the root. The fungus can remain in infected soil for years through chlamydospores. C. elegans thrives in highly acidic, organic soil, especially with large amounts of vitamin C. Damaged carrots in areas of high temperatures are more susceptible to accelerated growth of black root rot. ^[22]

Crown Rot

Crown rot, or Rhizoctonia solani, is a soilborne fungus. It attacks roots nearing maturity in carrots and may result in the death or severe weakening of seeds before or after germination. Crown rot is most prevalent in wet areas in warm climates. Symptoms on the roots of carrot are typically brown-black deep lesions or cankers near the crown or other root parts. Overall the rotting process is dry, unlike other carrot fungus'. R. solani can survive through winter or longer on the debris of plants. Greatest risk to infection occurs at high humidity with temperatures greater than 64 °F. Easily spreadable in closely planted fields. The rotation of fields, removing of plant debris after harvest and enhanced soil drainage and air circulation are highly recommended to reduce R. solani survival and infection.^[22]

Fusarium Dry Rot

Fusarium dry rot of carrot is caused by Fusarium spp,. The soilborne fungi can grow wherever carrots are found. Fusarium dry rot is also called a carrot root disease, but it can also attack the seeds. The fungus develops after full maturity and/or in storage. Fusarium spp, can survive in many ways including plant debris/residue or in mycelia. Wet, warm temperatures as well as wounds on the root can result in the growth of Fusarium spp. Symptoms include brown, leathery lesions, side cankers and the decay of the crown of the carrot. Dry, cold storage of carrots after cultivation can stop Fusarium dry rot from continuing to develop. ^[22]

See also

• List of beneficial weeds
• List of companion plants
• Daucus pusillus, American wild carrot
• Plant Profile of Daucus carota L.^[23]

References

Further reading

• Blanchan, Neltje (2005). Wild Flowers Worth Knowing. Project Gutenberg Literary Archive Foundation. 
• Bradeen, James M.; Simon, Philipp W. (2007). "Carrot". In Cole, Chittaranjan. Vegetables. Genome Mapping and Molecular Breeding in Plants. 5. New York, New York: Springer. pp. 162–184. ISBN 978-3-540-34535-0. 
• Clapham, A. R.; Tutin, T. G.; Warburg, E. F. (1962). Flora of the British Isles. Cambridge University Press. 
• Mabey, Richard (1997). Flora Britannica. London: Chatto and Windus. 
• Rose, Francis (2006). The Wild Flower Key (edition revised and expanded by Clare O'Reilly). London: Frederick Warne. ISBN 0-7232-5175-4. 
• Rubatsky, V.E.; Quiros, C.F.; Siman, P.W. (1999). Carrots and Related Vegetable Umbelliferae. CABI Publishing. ISBN 978-0-85199-129-0. 

External links

Wikimedia Commons has media related to Daucus carota.

• Connecticut Botanical Society