Sunday, January 1, 2012

Carrot cultivation



Scientific classification
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Kingdom        : Plantae
(unranked)      : Angiosperms
(unranked)      : Eudicots
(unranked)      : Asterids
Order             : Apiales
Family            : Apiaceae
Genus             : Daucus
Species           : D. carota
Binomial name : Daucus carota
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The carrot (Daucus carota subsp. sativus, Etymology: from Late Latin carōta, from Greek καρότον karōton, originally from the Indo-European root ker- (horn), due to its horn-like shape) is a root vegetable, usually

orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh. The most commonly eaten part of a carrot is a taproot, although the greens are edible as well. It is a domesticated form of the wild carrot Daucus carota, native to Europe and southwestern Asia. The domestic carrot has been selectively bred for its greatly enlarged and more palatable, less woody-textured edible taproot.

Description


It is a biennial plant which grows a rosette of leaves in the spring and summer, while building up the stout taproot, which stores large amounts of sugars for the plant to flower in the second year. The flowering stem grows to about 1 metre (3 ft) tall, with an umbel of white flowers that produce a fruit called a mericarp by botanists, which is a type of schizocarp.

Habitat

Habitat for carrots is mainly limited by temperature. While types of carrots can be found just about anywhere, Daucus carota var. sativus grows best in temperate zones. When grown outside of temperate zones cultivation techniques are needed in order to replicate cooler temperatures. Increased elevation is often used in subtropical areas to help reduce temperature and increase crop yields. Other factors in addition to temperature do contribute to the preferred habitat for Daucus carota var. sativus but temperature plays the largest role.

Other factors that make up the habitat of Daucus carota var. sativus include soil, sun exposure, nutrition, and drainage. Almost any type of soil is suitable to grow Daucus carota var. sativus , but the plants tend to prefer loam. Loam is a type of soil that is a hybrid of sand and clay. In addition to loam, carrots require a moist, yet well drained soil. If the soil becomes wet conditions become favorable for fungi to grow and interactions, which are explained in the interaction section of this page, begin to develop. The nutrition content of the soil is also a factor in the growth of Daucus carota var. sativus. If soil is devoid of nutrient it is unlikely that carrots will thrive in the area. It is preferred that the soil has a relatively high content of organic material to provide adequate nutrients. Lastly, Daucus carota var. sativus prefers to be located where the plant can receive full sunlight. Full sunlight allows the plant to reach optimal growth levels.

Daucus carota var. sativus is a plant developed from wild varieties for cultivation. The conditions under which carrots are grown are highly monitored to ensure optimal growth. All species that occupy the same habitat are considered competition and measures are taken to eradicate them. Major producers of carrots include China, The United States, and Russia. These three countries account for a large portion of the commercial cultivation.

Methods of consumption and uses


Carrots can be eaten in a variety of ways. Only 3% of the β-carotene in raw carrots is released during digestion: this can be improved to 39% by pulping, cooking and adding cooking oil.Alterrnatively they may be chopped and boiled, fried or steamed, and cooked in soups and stews, as well as baby and pet foods. A well known dish is carrots julienne. Grated carrots are used in carrot cakes, as well as carrot puddings, an old English dish thought to have originated in the early 19th century. The greens are edible as a leaf vegetable, but are rarely eaten by humans. Together with onion and celery, carrots are one of the primary vegetables used in a mirepoix to make various broths.

In India carrots are used in a variety of ways, as salads or as vegetables added to spicy rice or daal dishes. The most popular variation in north India is the Gaajar Kaa Halwaa carrot dessert, which has carrots grated and cooked in milk until the whole mixture is solid, after which nuts and butter are added. Carrot salads are usually made with grated carrots in western parts with a seasoning of mustard seeds and green chillies popped in hot oil, while adding carrots to rice usually is in julienne shape.

The variety of carrot found in north India is rare everywhere except in Central Asia and other contiguous regions, and is now growing in popularity in larger cosmopolitan cities in South India. The north Indian carrot is pink-red comparable to plum or raspberry or deep red apple in colour (without a touch of yellow or blue) while most other carrot varieties in world are from orange to yellow in colour, comparable to hallowe'en pumpkins.

Ever since the late 1980s, baby carrots or mini-carrots (carrots that have been peeled and cut into uniform cylinders) have been a popular ready-to-eat snack food available in many supermarkets.

Carrot juice is also widely marketed, especially as a health drink, either stand-alone or blended with fruits and other vegetables.

Companion plant

Carrots are useful companion plants for gardeners. There is experimental evidence[citation needed] that growing it intercropped with tomatoes increases tomato production. If left to flower, it (like any umbellifer) attracts predatory wasps which kill many garden pests.

Nutrition

Daucus carota var. sativus creates its own food through a process called photosynthesis. Plants that produce their own food are called autotrophs and make up the base of the food web. The carrots placement at the base of the food web explains why it serves as a source of food for many of the organisms it interacts with.

Photosynthesis is a complex process that Daucus carota var. sativus uses to create its own food. This process utilizes CO2 as a source of carbon to create sugars, which nourish the plant. The basic equation for this process is carbon dioxide + water + energy = sugar + oxygen + water.

Carrot, raw Nutritional value per 100 g (3.5 oz)
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Energy                     173 kJ (41 kcal)
Carbohydrates             9 g
- Sugars                       5g
- Dietary fibre               3 g
Fat                            0.2 g
Protein 1 g
Vitamin A equiv.       835 μg (104%)
- beta-carotene       8285 μg (77%)
- lutein and zeaxanthin 256 μg
Thiamine (vit. B1)      0.04 mg (3%)
Riboflavin (vit. B2)     0.05 mg (4%)
Niacin (vit. B3)          1.2 mg (8%)
Vitamin B6                 0.1 mg (8%)
Folate (vit. B9)         19 μg (5%)
Vitamin C                   7 mg (8%)
Calcium                    33 mg (3%)
Iron                       0.66 mg (5%)
Magnesium               18 mg (5%)
Phosphorus               35 mg (5%)
Potassium                240 mg (5%)
Sodium                     2.4 mg (0%)

Carrot seeds

The carrot gets its characteristic and bright orange colour from β-carotene, which is metabolised into vitamin A in humans when bile salts are present in the intestines. Massive overconsumption of carrots can cause

carotenosis, a benign condition in which the skin turns orange. Carrots are also rich in dietary fibre, antioxidants, and minerals.

Lack of vitamin A can cause poor vision, including night vision, and vision can be restored by adding it back into the diet. An urban legend says eating large amounts of carrots will allow one to see in the dark. The legend developed from stories of British gunners in World War II, who were able to shoot down German

planes in the darkness of night. The legend arose during the Battle of Britain when the RAF circulated a story about their pilots' carrot consumption as an attempt to cover up the discovery and effective use of radar technologies in engaging enemy planes, as well as the use of red light (which does not destroy night vision) in aircraft instruments. It reinforced existing German folklore and helped to encourage Britons—looking to improve their night vision during the blackouts—to grow and eat the vegetable.

Ethnomedically, the roots are used to treat digestive problems, intestinal parasites, and tonsillitis or constipation.

History


The wild ancestors of the carrot are likely to have come from Iran and Afghanistan, which remains the centre of diversity of D. carota, the wild carrot. Selective breeding over the centuries of a naturally occurring subspecies of the wild carrot, Daucus carota subsp. sativus, to reduce bitterness, increase sweetness and minimise the woody core, has produced the familiar garden vegetable.

 In early use, carrots were grown for their aromatic leaves and seeds, not their roots. Some relatives of the carrot are still grown for these, such as parsley, fennel, dill and cumin. The first mention of the root in classical sources is in the 1st century. The modern carrot appears to have been introduced to Europe in the 8–10th centuries.The 12th c. Arab Andalusian agriculturist, Ibn al-'Awwam, describes both red and yellow carrots; Simeon Seth also mentions both colours in the 11th century. Orange-coloured carrots appeared in the Netherlands in the 17th century. These, the modern carrots, were intended by the antiquary John Aubrey (1626–1697) when he noted in his memoranda "Carrots were first sown at Beckington in Somersetshire Some very old Man there [in 1668] did remember their first bringing hither."

In addition to wild carrot, these alternative (mostly historical) names are recorded for Daucus carota: bee's-nest, bee's-nest plant, bird's-nest, bird's-nest plant, bird's-nest root, carota, carotte (French), carrot, common carrot, crow's-nest, daucon, dawke, devil's-plague, fiddle, gallicam, garden carrot, gelbe Rübe (German), gingidium, hill-trot, laceflower, mirrot, Möhre (German), parsnip (misapplied), Queen Anne's lace, rantipole, staphylinos, and zanahoria (Spanish).

Cultivation

Carrots grow best in full sun but tolerate some shade In order to avoid growing deformed carrots it is better to plant them in loose soil free from rocks. The seeds, which are 1-3mm in diameter, should be sown about
11 day old carrot plants in a sand bed

2cm deep. Carrots take around 4 months to mature and it is suggested that carrot seeds are sown from mid - February to July.
carrot field

Cultivars

There are different colors of carrots now available in the markets  . They are of Atomic Red, Bambino, Cosmic Purple, Lunar White and Solar Yellow. Smoothly tapered roots grow to 8 inches x 2 inches in loose soil.


Carrot cultivars can be grouped into two broad classes, eastern carrots and western carrots. More recently, a number of novelty cultivars have been bred for particular characteristics.

The city of Holtville, California, promotes itself as "Carrot Capital of the World", and holds an annual festival devoted entirely to the carrot.

Eastern carrots



Eastern carrots were domesticated in Central Asia, probably in modern-day Iran and Afghanistan in the 10th century, or possibly earlier. Specimens of the eastern carrot that survive to the present day are commonly

purple or yellow, and often have branched roots. The purple colour common in these carrots comes from anthocyanin pigments.

Western carrots

The western carrot emerged in the Netherlands in the 17th century, from Iran with violet colour, its orange colour making it popular in those countries as an emblem of the House of Orange and the struggle for Dutch independence. The orange colour results from abundant carotenes in these cultivars. While orange carrots are the norm in the West, other colours do exist, including white, yellow, red, and purple. These other colours of carrot are raised primarily as novelty crops.

Western carrot cultivars are commonly classified by their root shape:
Chantenay carrots are shorter than other cultivars, but have greater girth, sometimes growing up to 8 centimetres (3 in) in diameter. They have broad shoulders and taper towards a blunt, rounded tip. They are most commonly diced for use in canned or prepared foods.
Danvers carrots have a conical shape, having well-defined shoulders and tapering to a point at the tip. They are somewhat shorter than Imperator cultivars, but more tolerant of heavy soil. Danvers cultivars are often puréed as baby food. They were developed in 1871 in Danvers, Ma.
Imperator carrots are the carrots most commonly sold whole in United States supermarkets; their roots are longer than other cultivars of carrot, and taper to a point at the tip.
Nantes carrots are nearly cylindrical in shape, and are blunt and rounded at both the top and tip. Nantes cultivars are often sweeter than other carrots.

While any carrot can be harvested before reaching its full size as a more tender "baby" carrot, some fast-maturing cultivars have been bred to produce smaller roots[citation needed]. The most extreme examples produce round roots about 2.5 centimetres (1 in) in diameter. These small cultivars are also more tolerant of heavy or stony soil than long-rooted cultivars such as 'Nantes' or 'Imperator'. The "baby carrots" sold ready-to-eat in supermarkets are, however, often not from a smaller cultivar of carrot, but are simply full-sized carrots that have been sliced and peeled to make carrot sticks of a uniform shape and size.

Carrot flowers are pollinated primarily by bees. Seed growers use honeybees or mason bees for their pollination needs.

Carrots are used as food plants by the larvae of some Lepidoptera species, including Common Swift, Garden Dart, Ghost Moth, Large Yellow Underwing and Setaceous Hebrew Character.

One particular variety lacks the usual orange pigment from carotenes, owing its white colour to a recessive gene for tocopherol (Vitamin E). Derived from Daucus carota L. and patented at the University of Wisconsin–Madison, the variety is intended to supplement the dietary intake of Vitamin E.

Orange Carrots


Orange carrots arrived from natural mutations of yellow forms, and then by human selection and development, probably in the Netherlands. It is thought that humans made selections from a genepool involving yellow rooted eastern carrots, cultivated white-rooted derivatives of wild carrot (grown as medicinal plants since classical times) and wild unselected populations of adjacent Daucus Carota subspecies in Europe and the Mediterranean. It is thought that Dutch breeders used a mutant seed from North Africa to develop the orange variety into a stable and reliable plant for domestication.

Some scholars think that orange carrots did not to appear until the 16th century, although there is a Byzantine manuscript of 512 ad, and an 11th century illuminated script, both of which depict an orange rooted carrot, and suggesting it was around long before.

Orange roots, containing the pigment carotene, were not noted until the 16th century in Holland. A tale, probably apocryphal, has it that the orange carrot was bred in the Netherlands in the seventeenth century to honour William of Orange. Though the stabilised orange carrot does date from around seventeenth century Netherlands, it is unlikely that honouring William of Orange had anything to do with it!

Experts believe the colour comes from beta carotene with some alpha carotene, a pigment the body converts to Vitamin A, which is essential for healthy skin and vision in dim light. Dutch breeders recently studied the health qualities of purple carrots and believe they give us extra protection against various forms of cancer and heart disease. They contain purple pigments called anthocyanins, and act as anti-oxidants that protect the body.

Purple Carrots

Purple Carrots come back from their roots - re-introduced to England .
The carrot returned to its roots and went on sale in the summer of 2002 in England in its original colour - purple - the first time in five centuries. There is also talk of bringing back black and white varieties together with a rainbow version!

Supermarket buyers were not too keen to try out purple carrots and sadly sales plummeted.. After pink tomatoes and green tomato ketchup they believed British consumers were keen to experiment.

Carrots are the second most popular vegetable after the potato. The first commercial crop was grown near Ely, Cambridgeshire, and dark purple carrots with orange insides were sold at Sainsbury's stores in July. They attempted to brighten up the nation's dinner plates served as a violet purée, with its classic partner, the green pea, or in a salad. These carrots  are different and have had a little extra care and attention in the way they have been raised.

These carrots are  healthy and  sweeter. They also look stunning sliced raw.This  unusual colour will influence children to eat more vegetables while parents can rest assured that there is nothing artificial about the carrots.

Purple carrots are being explored as a source of such dyes is the purple carrot, ancient ancestor to the modern, orange version. Originally used as a clothing dye by Afghan royalty, the purple carrot is now being investigated as a potential source of food colorings. Researchers are at work to stabilize the purple pigment in the vegetables, which can turn brown when heated, red in acidic foods and blue in alkaline ones.

The carrots are given their purple colour by anthocyanin, a powerful antioxidant that also gives blueberries and red grapes their colour.Purple carrots are now propositioned as the next superfood.

The findings of the recent Australian study revealed the ancient carrot to be packed with antioxidants and anti-inflammatory goodness - up tp 28 times more anthocyanins, which are antioxidants that are responsible for the purple-red pigment in raspberries and blueberries, than there are in orange carrots.

Purple carrots are the original carrots from the ancient Persia. These are  one of the wide variety of fruit and vegetables that are almost lost in the era of single supermarket varieties, just like other ancient tomato varieties.Purple carrots should be eaten coupled with a moderate diet and exercise.

Production trends

Carrot and Turnip output in 2005. Green: largest producer (China). Yellow: other major producers. Red: minor producers

In 2009, according to the Food and Agriculture Organization, 33.582 million tonnes of carrots and turnips were produced worldwide. With 15.168 million tonnes, China was by far the largest producer and accounted for 45.2 % of the global output, followed by Russia (1.518 million tonnes) and the United States (1.304 million tonnes).

Storage

Carrots can be stored for several months in the refrigerator or over winter in moist sand in a cool place.




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