Monday, November 26, 2012

Jujube tree

Its precise natural distribution is uncertain due to extensive cultivation, but is thought to be in southern Asia, between Lebanon, Iran, Pakistan, India, Bangladesh, Nepal (called as Bayar), the Korean peninsula, and southern and central China, and also southeastern Europe though more likely introduced there.[2] This plant has been reintroduced in Madagascar and grows as an invasive species in the western part of this island. It is a small deciduous tree or shrub reaching a height of 5–10 metres (16–33 ft), usually with thorny branches. The leaves are shiny-green, ovate-acute, 2–7 centimetres (0.79–2.8 in) wide and 1–3 centimetres (0.39–1.2 in) broad, with three conspicuous veins at the base, and a finely toothed margin. The flowers are small, 5 millimetres (0.20 in) wide, with five inconspicuous yellowish-green petals. The fruit is an edible oval drupe 1.5–3 centimetres (0.59–1.2 in) deep; when immature it is smooth-green, with the consistency and taste of an apple, maturing brown to purplish-black and eventually wrinkled, looking like a small date. There is a single hard stone similar to an olive stone.[2] NomenclatureThe species has a curious nomenclatural history, due to a combination of botanical naming regulations, and variations in spelling. It was first described scientifically by Carolus Linnaeus as Rhamnus zizyphus, in Species Plantarum in 1753. Later, in 1768, Philip Miller concluded it was sufficiently distinct from Rhamnus to merit separation into a new genus, in which he named it Ziziphus jujube, using Linnaeus' species name for the genus but with a probably accidental single letter spelling difference, 'i' for 'y'; for the species name he used a different name, as tautonyms (repetition of exactly the same name in the genus and species) are not permitted in botanical naming. However, because of Miller's slightly different spelling, the combination correctly using the earliest species name (from Linnaeus) with the new genus, Ziziphus zizyphus, is not a tautonym, and therefore permitted as a botanical name; this combination was made by Hermann Karsten in 1882.[2][3] NutrientsJujube, raw (NDB NO:09146) Nutritional value per 100 g (3.5 oz) Energy 331 kJ (79 kcal) Carbohydrates 20.23 g Fat 0.20 g Protein 1.20 g Water 77.86 g Vitamin A 40 IU Thiamine (vit. B1) 0.020 mg (2%) Riboflavin (vit. B2) 0.040 mg (3%) Niacin (vit. B3) 0.900 mg (6%) Vitamin B6 0.081 mg (6%) Vitamin C 69 mg (83%) Calcium 21 mg (2%) Iron 0.48 mg (4%) Magnesium 10 mg (3%) Phosphorus 23 mg (3%) Potassium 250 mg (5%) Sodium 03 mg (0%) Percentages are relative to US recommendations for adults. Source: USDA Nutrient Database Jujube, dried (NDB NO:09147) Nutritional value per 100 g (3.5 oz) Energy 1,201 kJ (287 kcal) Carbohydrates 73.60 g Fat 1.10 g Protein 3.70 g Water 19.70 g Vitamin A 40 IU Thiamine (vit. B1) 0.210 mg (18%) Riboflavin (vit. B2) 0.360 mg (30%) Niacin (vit. B3) 0.500 mg (3%) Vitamin B6 0.00 mg (0%) Vitamin C 13 mg (16%) Calcium 79 mg (8%) Iron 1.80 mg (14%) Magnesium 37 mg (10%) Phosphorus 100 mg (14%) Potassium 531 mg (11%) Sodium 09 mg (1%) Percentages are relative to US recommendations for adults. Source: USDA Nutrient Database Cultivation and usesJujube was domesticated in South Asia by 9000 BCE.[4] Over 400 cultivars have been selected. The tree tolerates a wide range of temperatures and rainfall, though it requires hot summers and sufficient water for acceptable fruiting. Unlike most of the other species in the genus, it tolerates fairly cold winters, surviving temperatures down to about −15 °C (5 °F). This enables the jujube to grow in mountain or desert habitats, provided there is access to underground water through the summer. The species Z. zizyphus grows in cooler regions of Asia. Five or more other species of Ziziphus are widely distributed in milder climates to hot deserts of Asia and Africa. [5]