Lychee ( , ; Litchi chinensis; ) is a monotypic taxon and the sole member in the genus Litchi in the soapberry family, Sapindaceae.
It is a tropical tree native to South China, Malaysia, and northern Vietnam. The tree has been introduced throughout Southeast Asia and South Asia. Cultivation in China is documented from the 11th century. China is the main producer of lychees, followed by Vietnam, India, other countries in Southeast Asia, other countries in the Indian subcontinent, Madagascar, and South Africa. A tall evergreen tree, it bears small fleshy sweet fruits. The outside of the fruit is a pink-red, rough-textured soft shell.
Lychee seeds contain methylene cyclopropyl glycine which has caused hypoglycemia associated with outbreaks of encephalopathy in undernourished Indian and Vietnamese children who consumed lychee fruit.
Taxonomy
Litchi chinensis is the sole member of the genus Litchi in the soapberry family, Sapindaceae.
It was described and named by French naturalist Pierre Sonnerat in his account "Voyage aux Indes Orientales et à la Chine, fait depuis 1774 jusqu'à 1781" (translation: "Voyage to the East Indies and China, made between 1774 and 1781"), which was published in 1782. There are three subspecies, determined by flower arrangement, twig thickness, fruit, and a number of stamens. Litchi chinensis subsp. chinensis is the only commercialized lychee. It grows wild in southern China, northern Vietnam, and Cambodia. It has thin twigs, flowers typically have six stamens, fruit are smooth or with protuberances up to . Litchi chinensis subsp. philippinensis (Radlk.) Leenh. It is common in the wild in the Philippines and rarely cultivated. It has thin twigs, six to seven stamens, long oval fruit with spiky protuberances up to . Litchi chinensis subsp. javensis. It is only known in cultivation, in Malaysia and Indonesia. It has thick twigs, flowers with seven to eleven stamens in sessile clusters, smooth fruit with protuberances up to .
Description
Tree
Litchi chinensis is an evergreen tree that is frequently less than tall, sometimes reaching . Its evergreen leaves, long, are pinnate, having 4 to 8 alternate, elliptic-oblong to lanceolate, abruptly pointed, leaflets,
The bark is grey-black, the branches a brownish-red. Its evergreen leaves are long, with leaflets in two to four pairs. Lychee are similar in foliage to the family Lauraceae, likely due to convergent evolution. They are adapted by developing leaves that repel water, and are called laurophyll or lauroid leaves.
Flowers grow on a terminal inflorescence with many panicles on the current season's growth. The panicles grow in clusters of ten or more, reaching or longer, holding hundreds of small white, yellow, or green flowers that are distinctively fragrant.
Fruit
The lychee bears fleshy fruits that mature in 80–112 days depending on climate, location, and cultivar. Fruits vary in shape from round to ovoid to heart-shaped, up to 5 cm long and 4 cm wide (2.0 in × 1.6 in), weighing approximately 20 g.
The thin, tough skin is green when immature, ripening to red or pink-red, and is smooth or covered with small sharp protuberances roughly textured. The rind is inedible but easily removed to expose a layer of translucent white fleshy aril with a floral smell and a sweet flavor. The skin turns brown and dry when left out after harvesting.
The fleshy, edible portion of the fruit is an aril, surrounding one dark brown inedible seed that is 1 to 3.3 cm long and 0.6 to 1.2 cm wide (0.39–1.30 by 0.24–0.47 in). Some cultivars produce a high percentage of fruits with shriveled aborted seeds known as 'chicken tongues'. These fruits typically have a higher price, due to having more edible flesh. Since the floral flavor is lost in the process of canning, the fruit is usually eaten fresh.
History
Cultivation of lychee began in the region of southern China, going back to 1059 AD, Malaysia, and northern Vietnam. Unofficial records in China refer to lychee as far back as 2000 BC. Wild trees still grow in parts of southern China and on Hainan Island. The fruit was used as a delicacy in the Chinese Imperial Court.
In the 1st century during the Han dynasty, fresh lychees were a popular tribute item, and in such demand at the Imperial Court that a special courier service with fast horses would bring the fresh fruit from Guangdong. There was great demand for lychee in the Song Dynasty (960-1279), according to Cai Xiang, in his Li chi pu (Treatise on Lychees). It was also the favorite fruit of Emperor Li Longji (Xuanzong)'s favored concubine Yang Yuhuan (Yang Guifei). The emperor had the fruit delivered at great expense to the capital.