Daucus carota L.
Family
Umbelliferae
Synonyms
Daucus gingidium L.
Vernacular Names
| Malaysia | Boktel, lobak merah. |
| English | Carrot. |
| Indonesia | Wortel, bortol (Sundanese). |
| Papua New Guinea | Karot, yalow pela sayor. |
| Philippines | Karot. |
| Cambodia | Karôt. |
| Thailand | Khaerot. |
| Vietnam | C[af] r[oos]t. |
| French | Carotte. |
Geographical Distributions
Daucus carota generally assumed that the purple (anthocyanin-containing) D. carota is originated in Afghanistan and the region where the Himalayan and Hindu Kush mountains are confluent. It is also domesticated in Afghanistan and adjacent regions of Russia, Iran, India, Pakistan and Anatolia. The purple D. carota together with a yellow variant, spread to the Mediterranean area and Western Europe in the 11-14th Centuries, and to China, India and Japan in the 14-17th Centuries. The orange (carotene-containing) D. carota probably arose in Europe or in the western Mediterranean region through gradual selection within yellow D. carota populations. The Dutch landraces Long Orange and the finer Horn types were the basis for the orange D. carota cultivars grown at present all over the world. In Asia, they have now largely replaced the purple and yellow types because of superior taste and nutritional value.
Description
D. carota is an annual or biennial erect herb that can grow up to 20-50 cm tall at the mature vegetative stage and can reach up to 120-150 cm tall when flowering.
Its taproot is fleshy, straight, conical to cylindrical, measures 5-50 cm long and measuring 2-5 cm in diametre at the top, orange (most common), reddish-violet, yellow or white.
The core (xylem) of mature roots is usually somewhat lighter in colour than the phloem and the top of the root is often green.
There are 8-12 leaves, growing in a rosette, hairless, green and with a long petiole that often sheathed at its base. The leaf-blade is 2-3-pinnate while the segments are divided into often linear ultimate lobes.
The flowering stalks are few to several branches where each branch ends in a compound umbel (inflorescence). Each umbel comprises of 50 or more umbellets, where each has up to about 50 flowers. The involucral bracts are more or less pinnatipartite. The primary rays are 2-25 cm long while the secondary rays are 1-6 cm long. The pedicels are 0.5-1.5 cm long. The flowers are mainly bisexual in the primary umbels. In the umbels of higher order an increasing number of male flowers may occur in addition to bisexual flowers. A few purple-red sterile flowers may be present in the central umbellets especially in wild plants. The flower is small, measuring 2 mm in diametre, epigynous, white, 5-merous but with 2 carpels and 2 styles.
The fruit is an oblong-ovoid schizocarp, measures 2-4 mm long and splits into 2 mericarps at maturity. The primary ridges are ciliate while the secondary ridges are with hooked spines.
The seed (inside the mericarp) is with a long embryo that embedded in endosperm. The seedling is long, with a thin taproot, cordate cotyledons and pinnate for the first true leaves.
Ecology / Cultivation
In their adaptation to the northern latitudes of Europe, D. carota became biennial and tolerant to long days (non-bolting) during the vegetative phase. It requires subsequent vernalisation at low temperatures to induce flowering. D. carota adapted to tropical and subtropical latitudes respond to long days by bolting even before the roots have properly thickened. D. carota is mostly cultivated as a cool season crop. The high soil temperatures, in excess of 25°C, induce slow growth rates, fibrous roots and low carotene content. For economic yields, D. carota should be grown in tropical regions at altitudes above 700 m. The early-maturing, D. carota cultivars may grow in the lowlands, but yields will be low and roots will have a poor colour. The optimum air temperatures are 16-24°C. Soils should be well-drained, fertile and with sandy texture. Heavy clay soils may induce malformed and twisted roots and harvesting will be difficult. The optimum pH is 6.0-6.5. A regular supply of water is essential to obtain smooth and even roots. Flowering and seed set are successful only in climates with mean day temperatures below 20°C.
Line Drawing / Photograph
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References
- Plant Resources of South-East Asia No. 8: Vegetables.
