Longan, commonly known as "Longan", is a rare specialty in the south subtropical region of China. Historically, the south "longan" and the north "ginseng". Longan fruit is rich in nutrition and has been loved by people since ancient times. It is regarded as a precious tonic with obvious nourishing effect. \x0d\ Brief introduction of scientific name Changguomu. The English name Longan \x0d\ alias Longan, Yizhilian and Yang Yan (Yunnan dialect) belong to Sapindaceae and Erguokan. Li Shizhen once had "Shijie, Dawuyuan, Yan Fu, Chu Liang, Yan Guang and Button Ming". According to the analysis, the pulp contains total sugar 12.38-22.55%, reducing sugar 3.85- 10. 16%, total acid 0.096-0. 109% and vitamin c43./kloc-0. Besides fresh food, longan can also be processed, dried, canned and fried. Longan has many functions, such as strengthening yang and benefiting qi, nourishing heart and strengthening spleen, nourishing blood and calming nerves, moistening skin and beautifying face. Can be used for treating anemia, palpitation, insomnia, amnesia, neurasthenia, and physical weakness after illness and postpartum. Modern medical practice has proved that it also has the effects of beauty beauty and prolonging life. Longan is very picky about the production environment, and there are limited places to grow longan in the world. Generally applicable to subtropical areas with mild climate and no severe frost. Among longan varieties, "Shijie" with big meat and small core is the best and the best to sell, and the price is relatively higher than other varieties. Therefore, longan has always been called a good fruit in Lingnan, because it can be eaten fresh and used as medicine, and the market is in short supply. \x0d\ Edit the characteristics of this paragraph \x0d\ Trees are evergreen and there are tall trees. Most of them are even pinnate compound leaves, and the leaflets are opposite or alternate; Panicle terminal or axillary; The fruit is spherical and the seeds are black and shiny. The flowering period is from March to April, and the fruiting period is from July to August. Like temperature and avoid freezing, the average annual temperature is 20 ~ 22℃, which is sensitive to low temperature; Generally, the annual average temperature is < 17.5 ~ 18℃, the Leng Yue average temperature is < 10℃, and the absolute low temperature is