The watermelon ( Citrullus lanatus) is a species of flowering plant in the family Cucurbitaceae, that has a large, edible fruit. It is a scrambling and trailing vine-like plant, and is plant breeding worldwide, with more than 1,000 varieties.
Watermelons are grown in favorable from tropics to temperate regions worldwide for its large edible fruit, which is a berry with a hard rind and no internal divisions, and is botany called a pepo. The sweet, juicy flesh is usually deep red to pink, with many black seeds, although seedless fruit varieties exist. The fruit can be eaten raw or pickled, and the rind is edible after cooking. It may also be consumed as a juice or an ingredient in mixed beverages.
Kordofan melons from Sudan are the closest relatives and may be of modern, cultivated watermelons. Wild watermelon seeds were found in Uan Muhuggiag, a prehistoric site in Libya that dates to approximately 3500 BC. In 2022, a study was released that traced 6,000-year-old watermelon seeds found in the Libyan desert to the Egusi seeds of Nigeria, West Africa. Watermelons were domesticated in north-east Africa and cultivated in Egypt by 2000 BC, although they were not the sweet modern variety. Sweet dessert watermelons spread across the Mediterranean world during Ancient Rome.
Considerable plant breeding effort has developed disease-resistant varieties. Many are available that produce mature fruit within 100 days of planting. China is the world's leading producer of watermelons with 64% of the total.
The large fruit is a kind of modified berry called a pepo with a thick rind (Pericarp) and fleshy center (mesocarp and endocarp). Wild plants have fruits up to in diameter, while cultivated varieties may exceed . The rind of the fruit is mid- to dark green and usually mottled or striped, and the flesh, containing numerous Seed spread throughout the inside, can be red or pink (most commonly), orange, yellow, green or white.
A bitter watermelon, Citron melon, has become naturalized in semiarid regions of several continents, and is designated as a "pest plant" in parts of Western Australia where they are called "pig melon".
The species is further divided into several varieties, of which bitter wooly melon ( Citrullus lanatus (Thunb.) Matsum. & Nakai var. lanatus), ( Citrullus lanatus var. citroides (L. H. Bailey) Mansf.), and the edible var. vulgaris may be the most important. This taxonomy originated with the erroneous synonymization of the wooly melon Citrullus lanatus with the sweet watermelon Citrullus vulgaris by L.H. Bailey in 1930.Bailey LH. 1930. Three discussions in Cucurbitaceae. Gentes Herbarum 2: 175–186. Molecular data, including sequences from the original collection of Thunberg and other relevant type material, show that the sweet watermelon ( Citrullus vulgaris Schrad.) and the bitter wooly melon Citrullus lanatus (Thunb.) Matsum. & Nakai are not closely related to each other. A proposal to conserve the name, Citrullus lanatus (Thunb.) Matsum. & Nakai, was accepted by the nomenclature committee and confirmed at the International Botanical Congress in 2017.
Prior to 2015, the wild species closest to Citrullus lanatus was assumed to be the tendril-less melon Citrullus ecirrhosus Cogn. from South African arid regions based on an erroneously identified 18th-century specimen. However, after phylogenetic analysis, the closest relative to Citrullus lanatus is now thought to be Citrullus mucosospermus (Fursa) from West Africa (from Senegal to Nigeria), which is also sometimes considered a subspecies within C. lanatus.Chomicki, Guillaume & Renner, Susanne S. 2015. Watermelon origin solved with molecular phylogenetics including Linnaean material: Another example of museomics. New Phytologist, 205 (2): 526–532. Watermelon populations from Sudan are also close to domesticated watermelons.Susanne Renner, A. Sousa, and G. Chomicki. 2017. Chromosome numbers, Sudanese wild forms, and classification of the watermelon genus Citrullus, with 50 names allocated to seven biological species. Taxon 66(6): 1393-1405 The bitter wooly melon was formally described by Carl Peter Thunberg in 1794 and given the name Momordica lanata. It was reassigned to the genus Citrullus in 1916 by Japanese botanists Jinzō Matsumura and Takenoshin Nakai.
Many 5000-year-old wild watermelon seeds ( C. lanatus) were discovered at Uan Muhuggiag, a prehistoric archaeological site located in southwestern Libya. This archaeobotanical discovery may support the possibility that the plant was more widely distributed in the past.
In the 7th century, watermelons were being cultivated in India, and by the 10th century had reached China. The Moors introduced the fruit into the Iberian Peninsula, and there is evidence of it being cultivated in Córdoba in 961 and also in Seville in 1158. It spread northwards through southern Europe, perhaps limited in its advance by summer temperatures being insufficient for good yields. The fruit had begun appearing in European by 1600, and was widely planted in Europe in the 17th century as a minor garden crop.
Early watermelons were not sweet, but bitter, with yellowish-white flesh. They were also difficult to open. The modern watermelon, which tastes sweeter and is easier to open, was developed over time through selective breeding.
European colonists introduced the watermelon to the New World. Spanish settlers were growing it in Florida in 1576. It was being grown in Massachusetts by 1629, and by 1650 was being cultivated in Peru, Colonial Brazil and Panama. Around the same time, Native Americans were cultivating the crop in the Mississippi valley and Florida. Watermelons were rapidly accepted in Hawaii and other Pacific islands when they were introduced there by explorers such as James Cook. In the Civil War era United States, watermelons were commonly grown by free black people and became one symbol for the abolition of slavery. After the Civil War, black people were maligned for their association with watermelon. The sentiment evolved into a racist stereotype where black people shared a supposed voracious appetite for watermelon, a fruit long associated with laziness and uncleanliness.
Seedless watermelons were initially developed in 1939 by Japanese scientists who were able to create seedless polyploid hybrids which remained rare initially because they did not have sufficient disease resistance. Seedless watermelons became more popular in the 21st century, rising to nearly 85% of total watermelon sales in the United States in 2014.
Major pests of the watermelon include , Drosophila, and root-knot nematodes. In conditions of high humidity, the plants are prone to Plant pathology such as powdery mildew and mosaic virus.
The US Department of Agriculture recommends using at least one beehive per acre ( per hive) for pollination of conventional, seeded varieties for commercial plantings. Seedless hybrids have sterile pollen. This requires planting pollinizer rows of varieties with viable pollen. Since the supply of viable pollen is reduced, and pollination is much more critical in producing the seedless variety, the recommended number of hives per acre increases to three hives per acre ( per hive). Watermelons have a longer growing period than other melons and can often take 85 days or more from the time of transplanting for the fruit to mature. Lack of pollen is thought to contribute to "hollow heart" which causes the flesh of the watermelon to develop a large hole, sometimes in an intricate, symmetric shape. Watermelons suffering from hollow heart are safe to consume.
Watermelons are important water sources in South Africa, the Kalahari Desert, and East Africa for both humans and animals.
The amino acid citrulline is produced in watermelon rind.
DNA data reveal that C. lanatus var. citroides Bailey is the same as Thunberg's bitter wooly melon, C. lanatus and also the same as C. amarus Schrad. It is not a form of the sweet watermelon C. vulgaris nor closely related to that species.
The citron melon or makataan – a variety with sweet yellow flesh that is cultivated around the world for fodder and the production of citron peel and pectin.
C. caffer Schrad. is a synonym of C. amarus Schrad.
The variety known as tsamma is grown for its juicy white flesh. The variety was an important food source for travellers in the Kalahari Desert.
Another variety known as karkoer or bitterboela is unpalatable to humans, but the seeds may be eaten.
A small-fruited form with a bumpy skin has caused poisoning in sheep.
This West African species is the closest wild relative of the watermelon. It is cultivated for cattle feed.
Additionally, other wild species have bitter fruit containing cucurbitacin.
C. colocynthis (L.) Schrad. ex Eckl. & Zeyh.,
C. rehmii De Winter, and
C. naudinianus (Sond.) Hook.f.
Others were also working on disease-resistant cultivars; J. M. Crall at the University of Florida produced 'Jubilee' in 1963 and C. V. Hall of Kansas State University produced 'Crimson Sweet' the following year. These are no longer grown to any great extent, but their lineage has been further developed into hybrid varieties with higher yields, better flesh quality and attractive appearance. Another objective of plant breeders has been the elimination of the seeds which occur scattered throughout the flesh. This has been achieved through the use of Polyploid varieties, but these are sterile, and the cost of producing the seed by crossing a Polyploid parent with a normal Polyploid parent is high.
As of 2017, farmers in approximately 44 states in the United States grew watermelon commercially, producing more than $500 million worth of the fruit annually. Georgia, Florida, Texas, California and Arizona are the United States' largest watermelon producers, with Florida producing more watermelon than any other state. This now-common fruit is often large enough that groceries often sell half or quarter melons. Some smaller, spherical varieties of watermelon—both red- and yellow-fleshed—are sometimes called "icebox melons". The largest recorded fruit was grown in Tennessee in 2013 and weighed .
The seeds have a nutty flavor and can be dried and roasted, or ground into flour. Watermelon rinds may be eaten, but their unappealing flavor may be overcome by pickling, sometimes eaten as a vegetable, stir frying or .
Citrullis lanatus, variety caffer, grows wild in the Kalahari Desert, where it is known as Citron melon. The fruits are used by the San people and wild animals for both water and nourishment, allowing survival on a diet of tsamma for six weeks.
Taxonomy
History
Systematics
Cultivation
+ Watermelon production 63.8 3.6 3.1 2.5 1.8 104.9
Production
Nutrition
Varieties
Citroides group
Lanatus group
Vulgaris group
Varieties
Variety improvement
Uses
Culinary
Symbolic
Gallery
See also
External links
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