Date palms reach up to 30 metres (100 feet) in height, growing singly or forming aclump with several stems from a single root system. Slow-growing, they can reach over 100years of age when maintained properly.[7] Date fruits (dates) are oval-cylindrical, 3 to 7 centimetres (1 to 3 inches) long, and about 2.5 cm (1 in) in diameter, with colour ranging from dark brown to bright red or yellow, depending on variety. Containing 61–68percent sugar by mass when dried,[8] dates are consumed as sweet snacks on their own or withconfections.
There is archaeological evidence of date cultivation in Arabia from the 6thmillennium BCE.[9] Dates are "emblematic ofoasis agriculture and highly symbolic in Muslim, Christian, and Jewish religions".[9]
Date palms reach up to 30 metres (100 feet) in height, growing singly or forming a clump with several stems from a single root system. Slow-growing, they can reach over 100 years of age when maintained properly.[7] The roots havepneumatodes.[10] Theleaves are 4–6 m (13–20 ft) long, with spines on thepetiole, andpinnate, with about 150 leaflets. The leaflets are 30 centimetres (12 inches) long and 2 cm (1 in) wide. The full span of the crown ranges from 6–10 m (20–33 ft).
The date palm isdioecious, having separate male and female plants. Like all members of genus Phoenix, sex determination occurs through anXY sex-determination system, where three genes that are conserved in all males and absent in all females have been identified.[11] They can be easily grown from seed, but only 50% of seedlings will be female and hence fruit-bearing, and dates from seedling plants are often smaller and of poorer quality. Most commercial plantations thus usecuttings of heavily cropping cultivars. Plants grown from cuttings will fruit 2–3 years earlier than seedling plants.
Phoenix dactylifera trunk section. As with other members of thepalm family, date palms do not produce annualtree rings.Leaves of the date palm
Dates are naturally wind-pollinated, but in traditional oasis horticulture and modern commercial orchards, they are entirelyhand-pollinated. Natural pollination occurs with about an equal number of male and female plants. With assistance, one male can pollinate up to 100 females. Since the males are of value only as pollinators, they are usually pruned in favor of fruit-producing female plants. Some growers do not maintain male plants, as male flowers become available at local markets at pollination time. Manual pollination is done by skilled labourers on ladders, or by use of a wind machine. In some areas, such as Iraq, the pollinator climbs the tree using a special climbing tool that wraps around the tree trunk and the climber's back (calledتبلية in Arabic) to keep him attached to the trunk while climbing.[citation needed]
Date fruits are oval-cylindrical, 3–7 cm (1–3 in) long, and 2–3 cm (3⁄4–1+1⁄4 in) diameter, and when ripe, range from bright red to bright yellow in colour, depending on variety. Dates contain a singlestone (seed) about2–2.5 cm (3⁄4–1 in) long and6–8 mm (1⁄4–5⁄16 in) thick. Three maincultivar groups exist:soft (e.g.,Medjool);semi-dry (e.g.,Deglet Noor), anddry (e.g.,Thoory).[citation needed]
A draft genome ofP. dactylifera (Khalas variety) was published in 2011[12] followed by more complete genome assemblies in 2013[13] and 2019.[14] The later study used long-read sequencing technology. With the release of this improved genome assembly, the researchers were able to map genes for fruit color and sugar content.[14] TheNYU Abu Dhabi researchers had also re-sequenced the genomes of several date varieties to develop the first single nucleotide polymorphism map of the date palm genome in 2015.[15]
The species namedactylifera 'date-bearing' isLatin, and is formed with the loanworddactylus in Latin fromGreekdaktylos (δάκτυλος), which means 'date' (also 'finger'),[16] and with the native Latinfero, which means 'to bear'.[17] Thefruit is known as a date.[18] The fruit's English name (throughOld French, throughLatin) comes from the Greek word for 'finger',δάκτυλος,[16] because of the fruit's elongated shape.
The place of origin of the date palm is uncertain because of long cultivation. According to some sources it probably originated from theFertile Crescent region straddlingEgypt andMesopotamia[6] while others state that they are native to thePersian Gulf area.[19] Fossil records show that the date palm has existed for at least 50 million years.[20]
A major palm pest, the red palm beetle (Rhynchophorus ferrugineus), currently poses a significant threat to date production in parts of the Middle East as well as to iconic landscape specimens throughout the Mediterranean world. Another significant insect pest isOmmatissus lybicus, sometimes called the "dubas bug", whose sap sucking results insooty mould formation.
In the 1920s, eleven healthyMedjool palms were transferred from Morocco to the United States where they were tended by members of theChemehuevi tribe[which?] in a remote region of Nevada. Nine of these survived and in 1935, cultivars were transferred to the U.S. Date Garden inIndio, California. Eventually this stock was reintroduced to Africa and led to the U.S. production of dates inYuma, Arizona andBard, California.[21]
Dates are a traditional crop throughout the Middle East and North Africa. Dates (especiallyMedjool andDeglet Nour) are also cultivated in the southwestern United States, and inSonora andBaja California in Mexico.
Date palms can take 4 to 8 years after planting before they will bear fruit, and start producing viable yields for commercial harvest between 7 and 10 years. Mature date palms can produce 70–140 kilograms (150–300 pounds)[22][23] of dates per harvest season. They do not all ripen at the same time so several harvests are required. To obtain fruit of marketable quality, the bunches of dates must be thinned and bagged or covered before ripening so that the remaining fruits grow larger and are protected from weather and animals, such as birds, that also like to eat them.
Date palms require well-drained deepsandy loam soils with a pH of 8–11 (alkaline). The soil should have the ability to hold moisture and also be free ofcalcium carbonate.[24]
Dates have been cultivated in the Middle East and the Indus Valley for thousands of years, and there is archaeological evidence of date cultivation inMehrgarh, a Neolithic civilization in western Pakistan, around 7000 BCE[25] and ineastern Arabia between 5530 and 5320calBC.[26] Dates have been cultivated since ancient times from Mesopotamia toprehistoric Egypt. Theancient Egyptians used the fruits to make datewine and ate dates at harvest.[citation needed] Evidence of cultivation is continually found throughout later civilizations in the Indus Valley, including theHarappan period from 2600 to 1900 BCE.[25]
Mazafati dates
Onecultivar, theJudean date palm, is renowned for its long-livedorthodox seed, which successfully sprouted after accidental storage for 2,000 years.[27] In total seven seeds about 2000 years old have sprouted and turned into trees named Methuselah, Hannah, Adam, Judith, Boaz, Jonah and Uriel.[28] The upper survival time limit of properly stored seeds remains unknown.[29] A genomic study from New York University Abu Dhabi Center for Genomics and Systems Biology showed that domesticated date palm varieties from North Africa, including well-known varieties such asMedjool andDeglet Nour, share large parts of their genome with Middle East date palms and the Cretan wild palms,P. theophrasti, as well as Indian wild palms,Phoenix sylvestris.
An article on date palm tree cultivation is contained inIbn al-'Awwam's 12th-century agricultural work,Book on Agriculture.[30]
A large number ofdate cultivars and varieties emerged through history of its cultivation, but the exact number is difficult to assess. Hussain and El-Zeid[32] (1975) have reported 400 varieties, while Nixon[33] (1954) named around 250. Most of those are limited to a particular region, and only a few dozen have attained broader commercial importance. The most renowned cultivars worldwide includeDeglet Noor, originally of Algeria; Yahidi and Hallawi of Iraq;Medjool of Morocco;Mazafati of Iran.[34]
Theglycemic index (GI) for different varieties of the date palm fruit is in the range of 38–71, with 53 on average,[37][39] indicating dates are a relatively low GI food source.[40] Theglycemic load (GL) value of date palm fruits, calculated for a serving size of three fruits (weighting 27 grams) is 9 on average, indicating that dates have low GL.[37]
Dry or soft dates are eaten out-of-hand, or may be pitted and stuffed with fillings such asalmonds,walnuts,pecans, candiedorange andlemonpeel,tahini,marzipan orcream cheese. Pitted dates are also referred to asstoned dates. Partially dried pitted dates may be glazed withglucose syrup for use as a snack food. Dates can also be chopped and used in a range of sweet and savory dishes, fromtajines (tagines) inMorocco topuddings,ka'ak (types of Arab cookies) and other dessert items. Date nut bread, a type of cake, is very popular in the United States, especially around holidays. Dates are also processed into cubes, paste called'ajwa, spread,date syrup or "honey" called "dibs" orrub in Libya, powder (date sugar),vinegar oralcohol. Vinegar made from dates was a traditional product of theMiddle East.[41][42] Recent innovations includechocolate-covered dates and products such as sparkling date juice, used in some Islamic countries as a non-alcoholic version ofchampagne, for special occasions and religious times such asRamadan. When Muslims break fast in theevening meal of Ramadan, it is traditional to eat a date first.
Reflecting the maritime trading heritage ofBritain, imported chopped dates are added to, or form the main basis of a variety of traditional dessert recipes includingsticky toffee pudding,Christmas pudding anddate and walnut loaf. They are particularly available to eat whole atChristmas time. Dates are one of the ingredients ofHP Sauce, a popular British condiment.
In Southeast Spain (where a large date plantation exists includingUNESCO-protectedPalmeral of Elche) dates (usually pitted with fried almond) are served wrapped inbacon and shallow-fried. In Palestine date syrup, termedsilan, is used while cooking chicken and also for sweets and desserts, and as a honey substitute. Dates are one of the ingredients ofjallab, a Middle Eastern fruit syrup. In Pakistan, a viscous, thick syrup made from the ripe fruits is used as a coating for leather bags and pipes to prevent leaking.
In the past, sticky dates were served using specialized small forks having two metal tines, calleddaddelgaffel in Scandinavia.[43] Some designs were patented.[44] These have generally been replaced by an inexpensive pale-colored knobbled plastic fork that resembles a date branch, which is traditionally included with numerous brands of prepackaged trays of dates, though this practice has declined in response to increased use of resealable packaging and calls for fewersingle-use plastics.
Date seeds are soaked and ground up foranimal feed. Their oil is suitable for use in cosmetics and dermatological applications. The oil containslauric acid (36%) andoleic acid (41%). Date palm seeds contain 0.56–5.4% lauric acid. They can also be processed chemically as a source ofoxalic acid. Date seeds are also ground and used in the manner ofcoffee beans, or as an additive to coffee. Experimental studies have shown that feeding mice with theaqueousextract of date pits exhibit anti-genotoxic effects and reduce DNA damage induced byN-nitroso-N-methylurea.[45]
In North Africa, date palm leaves are commonly used for making huts. Mature leaves are also made into mats, screens, baskets, and fans. Processed leaves can be used forinsulating board. Dried leafpetioles are a source ofcellulose pulp, used for walking sticks, brooms, fishing floats, and fuel. Leaf sheaths are prized for their scent, and fibre from them is also used for rope, coarse cloth, and large hats.
Young date leaves are cooked and eaten as a vegetable, as is the terminal bud or heart, though its removal kills the palm. The finely ground seeds are mixed withflour to make bread in times of scarcity. The flowers of the date palm are also edible. Traditionally the female flowers are the most available for sale and weigh300–400 grams (10+1⁄2–14 oz). The flower buds are used in salad or ground with dried fish to make acondiment for bread.
InAncient Rome, the palm fronds used intriumphal processions to symbolize victory were most likely those ofP. dactylifera.[48] The date palm was a popular garden plant in Romanperistyle gardens, though it would not bear fruit in the more temperate climate of Italy.[49] It is recognizable in frescoes fromPompeii and elsewhere in Italy, including a garden scene from the House of the Wedding of Alexander.[49] In later times, traders spread dates around southwest Asia, northern Africa, and Spain. Dates were introduced into California by the Spaniards by 1769, existing by then aroundMission San Diego de Alcalá, and were introduced to Mexico as early as the 16th century.[50]
Dates are mentioned more than 50 times in theBible and 20 times in theQuran. Date palms holds great significance inAbrahamic religions. The tree was heavily cultivated as a food source inancient Israel whereJudaism and subsequentlyChristianity developed.[51] Date palm leaves are used forPalm Sunday in the Christian religion.
Many Jewish scholars believe that the "honey" reference in Exodus chapter 3 to "a land flowing with milk and honey" is actually a reference to date "honey", and not honey from bees.[52] In theTorah, palm trees are referenced as symbols of prosperity and triumph.[53] Psalm 92:12 states that "The righteous shall flourish like the palm tree." Palm branches occurred as iconography in sculpture ornamenting theSecond Jewish Temple in Jerusalem, on Jewish coins, and in the sculpture of synagogues. They are also used as ornamentation in theFeast of the Tabernacles.[51] Date palms are one of theseven species of native Israeli plants revered in Judaism.[54] The date palm has historically been considered a symbol ofJudea and the Jewish people.[55] The leaves are used as alulav in the Jewish holiday ofSukkot.[56] They are also commonly used as thes'chach in the construction of asukkah.[57]
In the Quran,Allah instructsMaryām (the Virgin Mary) to eat dates during labour pains when she gives birth to Isa (Jesus).[58] InIslamic culture, dates and yogurt or milk are traditionally the first foods consumed forIftar after the sun has set duringRamadan.
InMandaeism, the date palm (Mandaic:sindirka, which can refer to both the tree and its fruit[59]) symbolizes thecosmic tree and is often associated with the cosmic wellspring (Mandaic:aina). The date palm, associated with masculinity, and wellspring, associated with femininity, are often mentioned together as heavenly symbols inMandaean texts.[60]
^Belarbi-Halli R, Mangenot F (1 August 1986). "Bayoud disease of date palm: ultrastructure of root infection through pneumatodes".Canadian Journal of Botany.64 (8):1703–1711.doi:10.1139/b86-228.ISSN0008-4026.
^Bonner FT (April 2008)."Chapter 4 Storage of Seeds"(PDF).Woody Plant Seed Manual, USDA FS Agriculture Handbook 727. National Seed Laboratory, 5675 Riggins Mill Rd, Dry Branch, GA 31020.Archived(PDF) from the original on 9 October 2022. Retrieved21 June 2008.
^Hussain F, El-Zeid A (1975). Studies on physical and chemical characteristics of date varieties of Saudi Arabia (Report). Ministry of Agriculture and Water, Saudi Arabia.
^Nixon R (1954). "Date culture in Saudi Arabia".Ann. Date Growers' Instit. (31):15–20.
^The Quran,Chapter 19 - verses 22-25Archived 2 April 2015 at theWayback Machine, retrieved on 28 Feb. 2015,So she [Virgin Mary] conceived him, and she retired with him to a remote place. And the pains of childbirth drove her to the trunk of a palm tree. she cried (in her anguish): 'Ah! would that I had died before this! would that I had been a thing forgotten and out of sight!' But (a voice) cried to her from beneath the (palm-tree): 'Grieve not! for thy Lord hath provided a rivulet beneath thee; And shake towards thyself the trunk of the palm-tree; it will let fall fresh ripe dates upon thee.'
^Drower ES (1960).The secret Adam: a study of Nasoraean gnosis. Oxford: Clarendon Press.
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