Persimmon belongs to the genus Persimmon in the family Persimmon, with about 25 species in the world and 3 species in China. Among them, edible persimmon has the greatest economic value. Persimmon grows vigorously, can adapt to all kinds of soil, has long life, high yield, less pests and diseases, easy cultivation and management, less labor, low cost and large income. Persimmon fruit is one of the popular fruits with bright color, beautiful posture, sweet taste and rich nutrition. Persimmon can replace grain to satisfy hunger, so it is called "woody grain". Persimmon fruit is not only a precious food, but also a rare Chinese medicine. Persimmon cream, for example, has a significant function in treating lung heat, dry cough, dry throat and sore throat, and sores on the mouth and tongue. Persimmon leaves can also be processed into persimmon leaf tea, which is suitable for patients with hepatitis, nephritis, coronary heart disease and hypertension to drink all the year round, and has the effects of stabilizing blood pressure, softening blood vessels, diminishing inflammation and removing heat. Persimmon paint is an important industrial raw material, so it can be seen that persimmon trees and persimmon fruits are widely used.
China is the hometown of persimmon trees, and wild persimmon trees are distributed in Yunnan, Sichuan, Hubei, Jiangsu, Zhejiang and other places. Today, the persimmon trees we cultivate are cultivated by the working people in our country from wild persimmon trees. In our country, people began to cultivate persimmon trees in the Zhou Dynasty, and it has a history of more than 3, years. It is recorded in ancient books such as Shangshu, Shennong Herbal Medicine and Erya. For a long time, through people's collection and selection, especially the grafting technology, a wide variety of persimmon varieties have been cultivated. At present, there are about 2-3 varieties cultivated all over the country. Due to the long-term influence of geographical conditions, these varieties are different in biological characteristics, which can be roughly divided into two groups: northern type and southern type. The northern persimmon has strong cold tolerance, likes cool and drought tolerance, thin skin and light yellow fruit color; The southern type has weak cold tolerance, poor drought resistance, thick peel and strong fruit color.
Persimmon trees are native to the Yangtze River valley with warm climate, which requires high temperature for growth, but also has considerable cold resistance. The annual average temperature in the suitable cultivation area must be greater than 9℃, and the absolute minimum temperature must be above -2℃. If the temperature drops below -2℃, persimmon trees will die from freezing injury. For example, in 1948, when the low temperature of -22℃ occurred in Xi 'an, Shaanxi Province, most persimmon trees were frozen to death. Persimmon is also a kind of fruit tree that likes light. Only in sunny environment can it grow well and have good quality. Therefore, persimmon cultivation should choose sunny slope. Persimmon is a drought-tolerant fruit tree, which is often planted on land with less water, such as hilly slopes, and can still grow normally. Usually planted in areas with annual rainfall of more than 5 mm, it can be irrigated without irrigation. However, the fruit-setting period is in the hot summer. If there is no rain for a long time, it must be irrigated in time to prevent fruit from falling and ensure high yield. Persimmon has a well-developed root system, strong water and fertilizer absorption capacity, and strong adaptability to soil, which can grow in both mountainous hills and sandy barren land. However, it is generally appropriate to use the soil with heavy texture, deep soil layer and neutral soil.
persimmon trees are widely distributed because of their strong adaptability to climate and soil. It is cultivated in all provinces and regions except Heilongjiang, Jilin, Inner Mongolia, Ningxia, Qinghai, Xinjiang and Tibet, which are extremely cold. The northern boundary of its distribution is roughly along the southern foot of Yanshan Mountain to Changping, turning to the southern foot of Taihang Mountain, passing through Huguan-Xixian County, Shanxi, entering Yichuan-Luochuan-Xianxian-Changwu, Shaanxi, and reaching Pingliang, Gansu. The western boundary starts from Pingliang in the north, goes south along the eastern foot of Liupanshan, passes through Tianshui to Ganzi, Sichuan, and reaches the territory of Yunnan Province directly. In the south and east of these two lines, the annual average temperature is above 1℃, and the annual rainfall is above 5 mm. Natural conditions such as light, heat, moisture and soil are conducive to the growth and development of persimmon trees, especially in central and southern Shaanxi, southwestern Shanxi, southwestern Hebei and central Henan and Shandong provinces, where the climate is cool and dry, which is more conducive to the growth of persimmon trees. The cultivated persimmon trees have high yield and good quality, and are well-known throughout the country. For example, a persimmon with a single fruit weighing 2-3g, orange flesh, sweet and greasy juice, can be transported and stored easily, and the fresh fruit can be stored until next February. Pointed persimmon produced in Fuping, Shaanxi Province, with a yield of 1,5-2, kg per plant, orange-red fruit color, dense pulp, thick slurry, sweet taste and most seedless, is most suitable for processing persimmon. In addition, there are sweet persimmons in Yixian County, Hebei Province and golden bottle persimmons in Qingdao, Shandong Province, which are also excellent varieties suitable for fresh eating and processing persimmons.
The geographical distribution of persimmon trees in China is not only restricted by latitude, but also closely related to altitude. The higher the latitude, the lower the altitude distribution. For example, the upper limit of persimmon distribution is 28 meters in the Anning River basin of Sichuan at 27-28 north latitude. In Taibai Mountain, Shaanxi Province, which is 33 59' north latitude, it is distributed at an altitude of 76 meters. This is mainly due to the rising latitude and decreasing temperature.
At present, persimmon production in China covers 18 provinces (cities, autonomous regions) such as Hebei, Henan, Shandong, Shanxi, Beijing, Tianjin, Anhui, Jiangsu, Zhejiang, Jiangxi, Hubei, Hunan, Guangdong, Guangxi, Yunnan, Guizhou, Shaanxi and Gansu. In 1985, the national persimmon output reached 13.596 million tons, an increase of 4.9% compared with 9.648 million tons in 1982. Among them, it accounts for about 72.3% of the total persimmon production in China. It is abundant in Shaanxi, Hebei, Henan, Shanxi and Shandong provinces, with Shaanxi producing the most, accounting for about 17% of the country. Followed by Hebei and Henan, accounting for 15% and 13.6% respectively.