Beta vulgaris


Beta vulgaris is a species of flowering plant in the subfamily Betoideae of the family Amaranthaceae. It is a perennial plant usually growing up to tall.
Three subspecies are typically recognised. The wild ancestor of all the cultivated beets is the sea beet, with several modern cultivars all belonging to B. vulgaris subsp. vulgaris.
Some of the most popular cultivar groups include: the sugar beet, the root vegetable known as the beetroot or garden beet, the leaf vegetable known as chard or spinach beet or silverbeet, and mangelwurzel.

Description

Beta vulgaris is a herbaceous biennial or, rarely, perennial plant up to in height, rarely 200 cm; cultivated forms are mostly biennial. The roots of cultivated forms are dark red, white, or yellow and moderately to strongly swollen and fleshy ; they are brown, fibrous, sometimes swollen, and woody in the wild subspecies. The stems grow erect or, in the wild forms, often procumbent; they are simple or branched in the upper part, and their surface is ribbed and striate. The basal leaves have a long petiole. The simple leaf blade is oblanceolate to heart-shaped, dark green to dark red, slightly fleshy, usually with a prominent midrib, with entire or undulate margin, 5–20 cm long on wild plants. The upper leaves are smaller, their blades are rhombic to narrowly lanceolate.
The flowers are produced in dense spike-like, basally interrupted inflorescences. Very small flowers sit in one- to three- flowered glomerules in the axils of short bracts or in the upper half of the inflorescence without bracts. The hermaphrodite flowers are urn-shaped, green or tinged reddish, and consist of five basally connate perianth segments, 3–5 × 2–3 mm, 5 stamens, and a semi-inferior ovary with 2–3 stigmas. The perianths of neighbouring flowers are often fused. Flowers are wind-pollinated or insect-pollinated, the former method being more important.
In fruit, the glomerules of flowers form connate hard clusters. The fruit is enclosed by the leathery and incurved perianth, and is immersed in the swollen, hardened perianth base. The horizontal seed is lenticular, 2–3 mm, with a red-brown, shiny seed coat. The seed contains an annular embryo and copious perisperm.
There are 18 chromosomes found in 2 sets, which makes beets diploid. Using chromosome number notation, 2n = 18.

Taxonomy

The species description of Beta vulgaris was made in 1753 by Carl Linnaeus in Species Plantarum, at the same time creating the genus Beta. Linnaeus regarded sea beet, chard and red beet as varieties. In the second edition of Species Plantarum, Linnaeus separated the sea beet as its own species, Beta maritima, and left only the cultivated beets in Beta vulgaris. Today sea beet and cultivated beets are considered as belonging to the same species, because they may hybridize and form fertile offspring. The taxonomy of the various cultivated races has a long and complicated history, they were treated at the rank of either subspecies, or convarieties or varieties. Now rankless cultivar groups are used, according to the International Code of Nomenclature for Cultivated Plants.
Beta vulgaris belongs to the subfamily Betoideae in family Amaranthaceae.
File:Beta vulgaris subsp maritima 89-08.JPG|thumb|Sea beet at the shores of Heligoland
Beta vulgaris is classified into three subspecies:
  • Beta vulgaris subsp. adanensis Ford-Lloyd & J.T.Williams : occurring in disturbed habitats and steppes of Southeast Europe and Western Asia.
  • Beta vulgaris subsp. maritima, sea beet, the wild ancestor of all cultivated beets. Its distribution area reaches from the coasts of Western Europe and the Mediterranean Sea to the Near and Middle East.
  • Beta vulgaris subsp. vulgaris Arcang., Beta vulgaris subsp. rapacea.: all cultivated beets belong to this subspecies. There are five cultivar groups:
  • * Altissima Group, sugar beet - The sugar beet is a major commercial crop due to its high concentrations of sucrose, which is extracted to produce table sugar. It was developed from garden beets in Germany in the late 18th century after the roots of beets were found to contain sugar in 1747.
  • * Cicla Group, spinach beet or chard - The leaf beet group has a long history dating to the second millennium BC. The first cultivated forms were believed to have been domesticated in the Mediterranean, but were introduced to the Middle East, India, and finally China by 850 AD. These were used as medicinal plants in Ancient Greece and Medieval Europe. Their popularity declined in Europe following the introduction of spinach. This variety is widely cultivated for its leaves, which are usually cooked like spinach. It can be found in many grocery stores around the world.
  • * Flavescens Group, swiss chard - Chard leaves have thick and fleshy midribs. Both the midribs and the leaf blades are used as vegetables, often in separate dishes. Some cultivars are also grown ornamentally for their coloured midribs. The thickened midribs are thought to have arisen from the spinach beet by mutation.
  • * Conditiva Group, beetroot or garden beet - This is the red root vegetable that is most typically associated with the word 'beet'. It is especially popular in Eastern Europe where it is the main ingredient of borscht.
  • * Crassa Group, mangelwurzel - This variety was developed in the 18th century from the garden beet for its tubers for use as a fodder crop.
File:chard3.jpg|thumb|right|Yellow-stemmed chard

Distribution and habitat

The wild forms of Beta vulgaris are distributed in southwestern, northern and Southeast Europe along the Atlantic coasts and the Mediterranean Sea, in North Africa, Macaronesia, to Western Asia. Naturalized they occur in other continents. The plants grow at coastal cliffs, on stony and sandy beaches, in salt marshes or coastal grasslands, and in ruderal or disturbed places.
Cultivated beets are grown worldwide in regions without severe frosts. They prefer relatively cool temperatures between 15 and 19 °C. Leaf beets can thrive in warmer temperatures than beetroot. As descendants of coastal plants, they tolerate salty soils and drought. They grow best on pH-neutral to slightly alkaline soils containing plant nutrients and additionally sodium and boron.

Ecology

Beets are a food plant for the larvae of a number of Lepidoptera species.

Cultivation

Beets are cultivated for fodder, for sugar, as a leaf vegetable, or as a root vegetable. It is the most important crop of the large order Caryophyllales.
"Blood Turnip" was once a common name for beet root cultivars for the garden. Examples include: Bastian's Blood Turnip, Dewing's Early Blood Turnip, Edmand Blood Turnip, and Will's Improved Blood Turnip.
The "earthy" taste of some beetroot cultivars comes from the presence of geosmin. Researchers have not yet answered whether beets produce geosmin themselves or whether it is produced by symbiotic soil microbes living in the plant. Breeding programs can produce cultivars with low geosmin levels yielding flavours more acceptable to consumers.
Beets are one of the most boron-intensive of modern crops, a dependency possibly introduced as an evolutionary response its pre-industrial ancestor's constant exposure to sea spray; on commercial farms, a 60 tonne per hectare harvest requires 600 grams of elemental boron per hectare for growth. A lack of boron causes the meristem and the shoot to languish, eventually leading to heart rot.

Red or purple coloring

The color of red/purple beetroot is due to a variety of betalain pigments, unlike most other red plants, such as red cabbage, which contain anthocyanin pigments. The composition of different betalain pigments can vary, resulting in strains of beetroot which are yellow or other colors in addition to the familiar deep red. Some of the betalains in beets are betanin, isobetanin, probetanin, and neobetanin. Other pigments contained in beet are indicaxanthin and vulgaxanthins. Indicaxanthin has been shown as a powerful protective antioxidant for thalassemia and prevents the breakdown of alpha-tocopherol.
Betacyanin in beetroot may cause red urine in people who are unable to break it down. This is called beeturia.
The pigments are contained in cell vacuoles. Beetroot cells are quite unstable and will 'leak' when cut, heated, or when in contact with air or sunlight. This is why red beetroots leave a purple stain. Leaving the skin on when cooking, however, will maintain the integrity of the cells and therefore minimize leakage.

Uses

Nutrition

In a 100 gram amount, beets supply 43 calories, contain 88% water, 10% carbohydrates, about 2% protein and have a minute amount of fat. The only micronutrients of significant content are folate and manganese.

Culinary

Spinach beet leaves are eaten as a pot herb. Young leaves of the garden beet are sometimes used similarly. The midribs of Swiss chard are eaten boiled while the whole leaf blades are eaten as spinach beet.
In some parts of Africa, the whole leaf blades are usually prepared with the midribs as one dish.
The leaves and stems of young plants are steamed briefly and eaten as a vegetable; older leaves and stems are stir-fried and have a flavour resembling taro leaves.
The usually deep-red roots of garden beet can be baked, boiled, or steamed, and often served hot as a cooked vegetable or cold as a salad vegetable. They are also pickled. Raw beets are added to salads. A large proportion of the commercial production is processed into boiled and sterilised beets or into pickles. In Eastern Europe beet soup, such as cold borsch, is a popular dish. Yellow-coloured garden beets are grown on a very small scale for home consumption.
The consumption of beets causes pink urine in some people.
Jewish people traditionally eat beet on Rosh Hashana. Its Aramaic name סלקא sounds like the word for "remove" or "depart"; it is eaten with a prayer "that our enemies be removed".