Date palm
Phoenix dactylifera, commonly known as the date palm, is a flowering-plant species in the palm family Arecaceae, native to the region from the Gulf States to Pakistan. It is cultivated for its edible sweet fruit called dates. The species is widely cultivated across northern Africa, the Middle East, Australia, South and Southeast Asia, Portugal, Spain, coastal Mediterranean basin, and the desert regions of Southern California. It is naturalised in many tropical and subtropical regions worldwide. P. dactylifera is the type species of genus Phoenix, which contains 12–19 species of wild date palms.
Date palms reach up to in height, growing singly or forming a clump with several stems from a single root system. Slow-growing, they can reach over 100years of age when maintained properly. Date fruit are oval-cylindrical, long, and about in diameter, with colour ranging from dark brown to bright red or yellow, depending on variety. Containing 63-64% sugar by mass when dried, dates are consumed as sweet snacks on their own or with confections.
There is archaeological evidence of date cultivation in Arabia from the 6thmillennium BCE. Dates are "emblematic of oasis agriculture and highly symbolic in Muslim, Christian, and Jewish religions".
Description
Date palms reach up to 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. The roots have pneumatodes. The leaves are long, with spines on the petiole, and pinnate, with about 150 leaflets. The leaflets are long and wide. The full span of the crown ranges from.The date palm is dioecious, having separate male and female plants. Like all members of genus Phoenix, sex determination occurs through an XY sex-determination system, where three genes that are conserved in all males and absent in all females have been identified. 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 use cuttings of heavily cropping cultivars. Plants grown from cuttings will fruit 2–3 years earlier than seedling plants.
File:דקל תמר מצוי חתך גזע דמוי עץ.jpg|thumb|Phoenix dactylifera trunk section. As with other members of the palm family, date palms do not produce annual tree rings.
Dates are naturally wind-pollinated, but in traditional oasis horticulture and modern commercial orchards, they are entirely hand-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 to keep him attached to the trunk while climbing.
Date fruit are oval-cylindrical, long, and diameter, and when ripe, range from bright red to bright yellow in colour, depending on variety. Dates contain a single stone about long and thick. Three main cultivar groups exist: soft ; semi-dry, and dry.
Genome
A draft genome of P. dactylifera was published in 2011 followed by more complete genome assemblies in 2013 and 2019. 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. The NYU 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.Etymology
The species name dactylifera 'date-bearing' is Latin, and is formed with the loanword dactylus in Latin from Greek daktylos, which means 'date', and with the native Latin fero, which means 'to bear'. The fruit is known as a date. The fruit's English name comes from the Greek word for 'finger', δάκτυλος, because of the fruit's elongated shape.The variety Phoenix dactylifera var. jubae, now considered a synonym for P. canariensis, was named after King Juba II.
Distribution
The place of origin of the date palm is uncertain because of long cultivation. According to some sources it probably originated from the Fertile Crescent region straddling Egypt and Mesopotamia while others state that they are native to the Persian Gulf area or derived from wild date palm from western India. Fossil records show that the date palm has existed for at least 50 million years.Ecology
A major palm pest, the red palm beetle, 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 is Ommatissus lybicus, sometimes called the "dubas bug", whose sap sucking results in sooty mould formation.In the 1920s, eleven healthy Medjool palms were transferred from Morocco to the United States where they were tended by members of the Chemehuevi tribe in a remote region of Nevada. Nine of these survived and in 1935, cultivars were transferred to the U.S. Date Garden in Indio, California. Eventually this stock was reintroduced to Africa and led to the U.S. production of dates in Yuma, Arizona and Bard, California.
Cultivation
Dates are a traditional crop throughout the Middle East and North Africa. Dates are also cultivated in the southwestern United States, and in Sonora and Baja 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 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 fruit grow larger and are protected from weather and animals, such as birds, that also like to eat them.
Date palms require well-drained deep sandy loam soils with a pH of 8–11. The soil should have the ability to hold moisture and also be free of calcium carbonate.
Agricultural history
Dates have been cultivated in the Middle East and the Indus Valley for thousands of years, and there is archaeological evidence of date cultivation in Mehrgarh, a Neolithic civilisation in western Pakistan, around 7000 BCE and in eastern Arabia between 5530 and 5320 calBC. Dates have been cultivated since ancient times from Mesopotamia to prehistoric Egypt. The ancient Egyptians used the fruit to make date wine and ate dates at harvest. In the Levant, the earliest traces of dates appear during the Chalcolithic period, at sites such as Nahal Mishmar and Teleilat el-Ghassul. Evidence of cultivation is continually found throughout later civilisations in the Indus Valley, including the Harappan period from 2600 to 1900 BCE.One cultivar, the Judean date palm, is renowned for its long-lived orthodox seed, which successfully sprouted after accidental storage for 2,000 years. In total seven seeds about 2000 years old have sprouted and turned into trees named Methuselah, Hannah, Adam, Judith, Boaz, Jonah and Uriel. The upper survival time limit of properly stored seeds remains unknown. 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 as Medjool and Deglet 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 in Ibn al-'Awwam's 12th-century agricultural work, Book on Agriculture. 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 around Mission San Diego de Alcalá, and were introduced to Mexico as early as the 16th century.
Cultivars
A large number of date cultivars and varieties emerged through history of its cultivation, but the exact number is difficult to assess. Hussain and El-Zeid have reported 400 varieties, while Nixon 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 include Deglet Noor, originally of Algeria; Yahidi and Hallawi of Iraq; Medjool of Morocco; Mazafati of Iran.Production
In 2024, world production of dates was 9.9 million tonnes, led by Saudi Arabia, Egypt, Algeria, and Iran, together accounting for 63% of the total.Nutrition
Deglet noor dates are 21% water, 75% carbohydrates, 2% protein, and less than 1% fat. In a reference amount of, dates supply of food energy, and are a rich source of potassium and a moderate source of pantothenic acid, vitamin B6, and the dietary minerals magnesium and manganese, with other micronutrients in low amounts. The primary carbohydrates are monosaccharides glucose, fructose, and sucrose .The glycemic index for different varieties of date palm fruit is in the range of 38–71, with 53 on average, indicating dates are a relatively low GI food source.
Uses
Fruit
Dry or soft dates are eaten in-the-hand, or may be stoned and stuffed with fillings such as almonds, walnuts, pecans, candied orange and lemon peel, tahini, marzipan or cream cheese. Stoned dates are also referred to as pitted dates. Partially dried stoned dates may be glazed with glucose syrup for use as a snack food. Dates can also be chopped and used in a range of sweet and savory dishes, from tajines in Morocco to puddings, ka'ak 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 calledReflecting the maritime trading heritage of Britain, imported chopped dates are added to, or form the main basis of a variety of traditional dessert recipes including sticky toffee pudding, Christmas pudding and date and walnut loaf. They are particularly available to eat whole at Christmas time. Dates are one of the ingredients of HP Sauce, a popular British condiment.
In Southeast Spain dates are served wrapped in bacon and shallow-fried. In Palestine date syrup, termed silan, is used while cooking chicken and also for sweets and desserts, and as a honey substitute. Dates are one of the ingredients of jallab, a Middle Eastern fruit syrup. In Pakistan, a viscous, thick syrup made from the ripe fruit is used as a coating for leather bags and pipes to prevent leaking.