Sweet potato (scientific name: sweet potato. ) Also called Ganchu, Sweet Potato, Bamboo Tree, Fanru, Red Yam, Jade Pillow Potato, Sweet Potato, Sweet Potato, Sweet Potato, Goose, Sweet Potato. Millet has round, oval or spindle-shaped tuberous roots in the underground part, and the stems are horizontal or ascending, with occasional twining and multi-branching. The shape and color of leaves often vary with varieties, usually with wide oval shape and different petioles. Cymes axillary, capsules ovoid or oblate, 1-4, usually 2, glabrous.

Sweet potato is native to South America and the big and small Antilles, and is widely planted in tropical and subtropical areas all over the world, and also in most parts of China.

Sweet potato is a kind of food crop with high yield and strong adaptability, which is closely related to industrial and agricultural production and people's life. Truffle is not only the main grain, but also an important raw material for food processing, starch and alcohol manufacturing industries. Roots, stems and leaves are excellent feeds.

Sweet potato was first planted in Mexico and Colombia in Central America, and then brought to the Philippines and other countries by the Spanish. [3] Sweet potato was introduced to China for the first time in Wanli period at the end of Ming Dynasty, and entered China in three ways-Yunnan, Guangdong and Fujian. [4]

It is generally believed that sweet potato was introduced into China in the Ming Dynasty, and Chen Yi was the first person to introduce sweet potato into China. According to historical records, Chen Yi was born in Beizha, Humen, Dongguan, Guangdong. In the eighth year of Wanli in the Ming Dynasty (1580), he dressed in cloth and wrapped his shoulders and set out for Annan (present-day Vietnam) by a friend's merchant ship. When they arrived in Annan, the local chiefs put on formal dishes when they received them. This dish is sweet and smooth. Besides being very delicious, it can also satisfy hunger. This is sweet potato. After that, Chen Yi paid special attention to the growth habits and cultivation methods of sweet potatoes. Two years later, on 1582, he risked his life, bribed a chief, hid potato seeds in a bronze drum and wanted to take them back to China secretly. Chen Yi bought 35 mu of land in front of his grandfather's grave on the hillside of Xiaojie Mountain in jinzhou area, Humen, and began to plant sweet potatoes on a large scale. After the harvest, he decided to spread food widely, and chose his longevity spot next to the potato field to stay with the sweet potato. As "the first person to introduce sweet potato in China", Chen Yi has made great contributions to the development of grain sources in China. [5][6]

In the Ming Dynasty, Chen Zhenlong, a native of Changle, Fujian, and his son Chen Jinglun, who had been doing business in Luzon (Philippines) for many years, saw a local root crop called "sweet potato", which was "as big as a fist, with scarlet skin, crisp and juicy heart, edible both raw and cooked, high yield and barren tolerance". Chen Zhenlong decided to introduce sweet potatoes to China when he thought of his hometown of Fujian, where there are many mountains and few fields, poor land and insufficient food. 1593, the Philippines was colonized by Spain and regarded sweet potato as an exotic product. After careful planning, Chen Zhenlong "screwed potato vines into the water rope" and smeared sludge on the rope surface. 1593 In the early summer, he cleverly escaped the inspection of the colonial checkpoint and "crossed the sea". Sail for seven days and return to Xiamen, Fujian in late May of the lunar calendar. Sweet potato is called "sweet potato" because it comes from abroad. Chen's introduction of sweet potato is discussed in Xu Guangqi's Agricultural Records and Tan Qian's Miscellaneous Jujube.

After sweet potato was introduced into China, it showed the excellent characteristics of strong adaptability and no occupation of land, and its yield was high, "the yield per mu was dozens of stones, which was 20 times better than that of seed grain". Coupled with "moist and edible, or boiled or ground into powder, raw food such as pueraria lobata, cooked food such as honey, taste like water chestnut", it can quickly spread to the mainland. At the beginning of the 17th century, serious floods occurred in the south of the Yangtze River, resulting in crop failure and displacement of hungry people. At that time, scientist Xu Guangqi was living in his home in Shanghai because of his father's death. He learned that the sweet potato planted in Fujian and other places is a good crop to save the famine, so he introduced it from Fujian to Shanghai and then to Jiangsu, and the harvest was good.

Chen Chuangui, the fifth grandson of Chen Zhenlong, introduced sweet potatoes to Zhejiang in the early years of Kangxi, and his son Chen Shiyuan took several younger generations to Henan, Hebei, Shandong and other places for extensive publicity to persuade them to plant sweet potatoes. According to the account, when Chen Shiyuan taught to grow sweet potatoes in the ancient town of Jiaozhou, Shandong Province, he personally cultivated seedlings, cut vines and branches, and harvested them in autumn, so he got a lot of potatoes, which were widely circulated and planted in competition. Sweet potato soon spread in North China.

During the Qianlong period, many places were planted by the government. In Zhili, the emperor even "encouraged planting in Zhili". Thanks to the active promotion of the government and the public, sweet potato soon spread widely throughout the country, becoming the fourth largest food crop in China after rice, wheat and corn. Sweet potato 1733 spread to Sichuan, 1735 spread to Yunnan and 1752 spread to Guizhou. Since then, traces of sweet potatoes have spread all over the southwest. [7]

morphological character

Panicum miliaceum, the underground part has round, oval or spindle-shaped roots. The shape, skin color and flesh color of tuberous roots vary with varieties or soils. Stems procumbent or ascending, occasionally twining, multi-branched, cylindrical or angular, green or purple, sparsely pilose or hairless, and stems are prone to adventitious roots.