Citrullus lanatus, watermelon, is an annual herbaceous plant in the squash family (Cucurbitaceae) that originated in subtropical Africa, was likely domesticated in the Mediterranean region and India, and is now cultivated in temperate to sub-tropical regions in Asia (from India through Southeast Asia to China), Japan, and North America for its large, juicy fruit.
C. lanatus is a monoecious vine, with branched tendrils, with deeply divided, hairy leaves; vines may grow to 2 meters in length. Flowers are yellow, 3-4 cm wide, with 5-parted corollas, and occur singly, in the axils (where leaves join stems). Fruits are known as pepos—a leathery rind covering soft juicy flesh, which ranges from red to pink to yellow, and containing many small hard dark-brown to black or occasionally tan seeds, although seedless varieties have been developed, in which seeds are mostly absent or small, soft, and white. Fruits are globose to oblong, with rinds that are light to dark green, or may be mottled or striped, and range in size from a 15 cm in diameter to 200+ cm in length (for oblong varieties). Fruits of typical varieties weigh from 4 to 14 kg (9 to 30 pounds), but the world’s heaviest recorded watermelon, grown in Arkadelphia, Arkansas, in 2005, weighed 121.93 kg (268.8 lb), as noted in
GuinnessWorldRecords.com, and was more than 1 meter long. The watermelon fruit, which has a high amount of water and a relatively low proportion of sugars, with moderate amounts of vitamins B and C, is used primarily as a fresh fruit, and is popular among dieters for its low calorie content. In some locales, the rinds are used to make pickles or chutneys. The edible seeds, which are high in oils and protein (45% and 30-405, respectively), are sometimes harvested and used in similar ways to pumpkin seeds, toasted and eaten as a snack (especially popular in the Middle East), pressed for oil, or used as a home remedy to treat pinworms and tapeworms in humans and livestock. Global production of watermelons in 2010 was 89.0 million metric tons,, harvested from 3.2 million hectares. China is by far the leading producer, responsible for 64% of the commercial harvest worldwide. Other leading producers include Turkey, Iran, Brazil, and the U.S. (FAOSTAT 2012, Purdue 2003, van Wyk 2005.)
