Sweet potato is a beef stem belonging to the conifer family. Among the Ipomoea species, sweet potato is probably the only one with edible tubers.
The sweet potato plant originated in the New World, was domesticated in pre-Columbian times, and spread to the Pacific Islands, where it became an important crop in New Zealand (Yen, 1974). With the formation and development of international trade, sweet potatoes spread rapidly to the tropics. The Spanish brought sweet potatoes from Misigo and the Philippines, and from there it spread to other islands. The Portuguese introduced sweet potato from the Caribbean and South America to Europe, Africa, Southeast Asia, and India (Yen, 1976). Sweet potato was introduced to Vietnam in the late 16th century, probably from Fujian (China) or Luzon Island in the Philippines.
Sweet potatoes were cultivated more than 5,000 years ago. Through recent studies, extensive archaeological, linguistic, agricultural, and ethnographic evidence suggests that South America was central from southern Mexico all the way to Central America and northern South America, especially northwestern The main origin of sweet potato. Yen (1982) proposed three routes for the spread and diffusion of sweet potato from primitive centers, with the Kamote route being spread by the Spanish directly from Mexico to the Philippines via Hawaii and Guam in the 16th century. From the South Pacific and the Philippines, sweet potatoes were spread to other Asian countries, including Vietnam.
Stem: Mainly bull, but there are also varieties with erect or climbing stems. Body length is sometimes up to 3-4 m, averaging about 1.5-2 m. Body diameter is usually small, about 0.3-0.6 cm. The stems have many nodes, each with a leaf. The average burning length is about 3-7 cm.
Leaves: alternate, with long stalks (up to 10 cm). Due to the long stalks, sweet potato leaves can rotate the leaves into the sun. Leaf shape and color depend on the variety: heart-shaped, lance-shaped, lobed (light, dark or propeller). Leaf color is light yellow, green, dark green.
Flowers: bell-shaped, with long stalks, like petunias. Flowers usually grow in leaf axils or at the top of the stem, alone or in clusters of 3-7 flowers, each flower opening only once in the early morning and fading at noon. The corolla is funnel-shaped, purple-pink, with petals joined together. Each flower has one female stamen and five male stamens of unequal height, which are lower than the female stamens.
Fruit: Sweet potatoes are squirrel-shaped, slightly round, with 3 skins and 1-4 seeds per fruit.
Seeds. Sweet potatoes are usually dark brown, oval or polygonal in shape, have a hard skin and can remain viable for 20 years or longer.
Tubers: elongated in shape, with smooth skin and red, purple, brown or white in color. Flesh layer is white, yellow, orange or purple