What is the distribution of red dates?

Deciduous perennial fruit trees and small trees of Zizyphus in Rhamnaceae. Also known as Jujube, Jujube and China Jujube. The scientific name is Zizyphus jujuba.

Origin and distribution

There are about 50 species of Zizyphus plants, but the main variety in fruit tree cultivation is Zizyphus jujuba, which originated in China and is one of the oldest fruit trees cultivated in China. China's ancient book The Book of Songs records "peeling dates in August"; "The Warring States Policy" describes that "there are dates and chestnuts in the north, and people are not allowed to go to the fields. Jujube chestnuts are solid and sufficient for the people "; Biography of Historical Records of Huo Zhi records that thousands of jujube trees were planted in Anyi, and its wealth can be compared with that of thousands of households. There are many varieties of jujube, including more than two species (2nd century BC) 10, 24 species in Western Jin Dynasty, 45 species in Qi Yao Min Shu in Northern Wei Dynasty, 73 species in Jujube Shop in Yuan Dynasty and 87 species in Textual Research on Plant Names and Facts in Qing Dynasty. Miocene jujube leaf fossils (from180,000 years ago) were discovered in Linqu County, Shandong Province. Zizyphus jujuba And jujube. They were found in Hemudu (6960-4887 BC) in Yuyao, Zhejiang Province and Qianshanyang (2750 BC) in Zhejiang Province. In recent years, carbonized jujube fruit and jujube stones have also been found in other areas, such as the tombs of Zenghou and Jingzhou River in Suixian County, Hubei Province, the Han Tomb of Mawangdui in Changsha, Hunan Province (dates and jujube stones unearthed from Tumawangdui), and the tombs of Lianyungang, Guangdong, Guangzhou, Zhao Hua, Sichuan, Wuwei, Gansu and Gao Changguo, Xinjiang.

Jujube is distributed in the range of N23 ~42.5 and E76 ~ 124 in China, almost all over the country. According to the 15℃ isotherm, the jujube cultivation areas are divided into two major flora, namely, the southern flora and the northern flora. The main distribution centers of the northern system are Shaanxi, Shanxi, Hebei, Shandong, Henan and other provinces; The main distribution centers of the Southern System are Sichuan, Hubei, Anhui, Zhejiang and other provinces. In Yunnan, Guizhou, Sichuan and other low latitude provinces, the distribution is as high as 2000 meters above sea level; Although the highest altitude in North China and Northwest China is 1.800 m, most of them are distributed in river valleys and beaches with an altitude of 1.000 ~ 1.000 m.. 1988, the output of fresh dates in China reached 520,000 tons.

China jujube spread to many parts of Asia in BC, such as Korea, Afghanistan, India, Pakistan, Thailand and the Asian part of the Soviet Union. 1 century spread to some countries along the Mediterranean coast, to Japan in the 8th and 9th centuries, and 1837 spread to the United States through Europe. However, few countries grow dates in the world economy.

Features and characteristics

Jujube varieties are different, but their morphological characteristics and fruiting habits have the same characteristics.

morphological character

The height of the tree is about 10 meter, and the trunk and old branches are light gray, cracked or cracked. Branches have acupuncture, stipules are abnormal, bending is different, and dates have no acupuncture; The fruit leaves and droops, and falls off in the autumn of that year. Leaves alternate, ovate or ovate-lanceolate, with three main veins. Small flowers, axillary incomplete cymes, round disk, rich in honey; Stamens 5, style 2-lobed. The fruit is drupe, and its shape and size vary with varieties, including round, oval, oval, chicken heart-shaped, spindle-shaped, long cylindrical, gourd-shaped and so on. The peel is bright red, purplish red or purplish brown; The nucleus is sharp and hard, and some nuclei degenerate into membranes, with or without nucleoli inside.

Growth habit

Jujube trees have a long life span, usually 70 to 80 years. Some jujube producing areas in China have preserved ancient jujube trees for hundreds of years and more than 1000 years, and they are still bearing fruit. For example, a lying jujube in Zhouyin Village, Zhanghou Township, Qingyun County, Shandong Province is estimated to be 1300 years old, and now it bears 50 ~ 100 kg of fruit all the year round; A jujube tree in Wangsuli Village, Laoshe Ancient Town, Qingjian County, Shaanxi Province, is estimated to be 900 years old and can still bear fruit every year. The root system of jujube has strong growth ability and developed horizontal roots, which are 3 ~ 6 times larger than the crown diameter, and most of them are in the deep soil layer of 15 ~ 40 cm, which is prone to root tillering; Vertical roots grow weakly. There are main buds (positive buds or winter buds) and secondary buds (summer buds) between the axils of jujube branches. The main bud is planted on the top or side of jujube head and jujube receptacle between the axils of primary and secondary branches of jujube head. Most of them do not germinate in the current year, but germinate into jujube receptacle or new jujube head in the next year, and sometimes they do not germinate into hidden buds. The life span of this hidden bud is as long as 30 years. Secondary buds are attached to the nodes of primary and secondary branches, and only secondary branches, tertiary branches or jujube hanging can be germinated. They germinated that year and could not survive the winter. Jujube branches are divided into jujube heads, jujube stocks and jujube hangings. Both jujube head and jujube rootstock germinate from the main bud, but the secondary branch of jujube head germinates from the secondary bud, which is the main branch of jujube rootstock. Jujube hanging is the fruiting branch of jujube tree, which is formed by germination and growth of jujube rootstock and auxiliary buds at the base of jujube head. Generally, it is 10 ~ 18 nodes, with the largest leaf area and the largest fruit setting in the middle node (see figure).

Fruiting habit

Jujube trees bear fruit early and can blossom and bear fruit in the same year of planting. The results mainly depend on the jujube rootstock, which is the unique shortened fruiting mother branch of jujube, and the annual growth is very small, only about 0.2 cm. Once formed, jujube hangs on it every year to blossom and bear fruit. Generally, 3-5-year-old jujube stocks are strong. Only 1 ~ 2 is too weak to hang 3 ~ 5 jujubes on a jujube rootstock. There is an inflorescence between the axils of each leaf, usually about 8 flowers, and at most about 12 flowers. Jujube with a length of 15 cm blooms 40 ~ 80 flowers on average, and generally bears 1 ~ 4 flowers a day. Jujube has a long flowering period, about 2-3 months. As long as the conditions are suitable, the flowers at all stages can bear fruit, but the later flowering is poor. Jujube has a large number of flowers and fruits, for example, the fruit setting rate of Shandong Laoling Jinsixiaozao is 0.42- 1.60%.

phenophase

Jujube trees germinate and bloom later than other deciduous fruit trees. In North China, it usually germinates in late April, blooms in late May, fruits are colored in late August, and mature in late September. The growth period is about 175 days.

Requirements for environmental conditions

Jujube has a wide range of temperature adaptation, which is both heat-resistant and cold-resistant. It can withstand the high temperature of 40℃ in growth period and the low temperature of -35℃ in dormancy period. Generally, the average annual temperature suitable for the growth of northern jujube is 9 ~ 14℃, and that of southern jujube is 15℃. Different phenological periods have different requirements on temperature: in general, the average daily temperature in spring reaches 13 ~ 16℃, when it reaches 17℃, it begins to sprout, spread leaves and differentiate flower buds, when it reaches 20℃, it enters full bloom at 22 ~ 25℃, and when it reaches 24 ~ 25℃, it is favorable for pollen germination. The suitable temperature for fruit ripening is 18 ~ 22℃, the soil temperature for root growth is above 7.2℃, and the growth peak is 22 ~ 25℃.

Jujube has a wide range of adaptation to precipitation. Jujube trees can also grow normally in places where the annual precipitation in Zhejiang and Anhui is 1000 ~ 1200mm and that in Guangdong is 1500mm. Jujube grows well in the production areas with annual precipitation of 200 ~ 300mm in Gansu and 400 ~ 600mm in North China. Jujube trees need high air humidity when they bloom. For example, when the air relative humidity of jujube is lower than 40%, the pollen germination rate is only 8.5%, and when the air relative humidity is higher than 70%, it is beneficial to pollination and fertilization. Fruit ripening requires low air humidity. If continuous rainfall affects fruit development and sugar accumulation, it will cause fruit cracking and rotten fruit, resulting in reduced production.

Jujube is a light-loving tree species. Too dense planting will affect the growth of branches, and the growth of jujube head and jujube hanging is poor, resulting in less fruit. As far as light is concerned, jujube trees should be planted on sunny and semi-sunny slopes in mountainous areas.

Jujube has a wide adaptability to soil. Besides heavy clay, it can adapt to gravel soil, sandy soil, loam soil, clay loam soil or clay, acid soil or alkaline soil. Mountains, hills and plains can be planted. Generally, it grows vigorously on sandy loam with deep soil layer and has high yield; The suitable soil pH value is 5.5 ~ 8.4. Jujube also has strong salt tolerance, which is normal in soil with total salt content below 0.2 ~ 0.3%.

principal item

There are about 500 jujube varieties in China, including jujube and jujube.

jujube

The fruit is large, with an average weight of more than 8 grams. This kind of tree is strong, adaptable, with large crown and dark leaves. Varieties are ① Zanhuang Jujube. Produced in Zanhuang, Hebei Province, it is a variety of fresh food and dry food. The developing branches have strong ductility, poor branching and sparse crown. The fruit is large, tidy and rectangular, with an average weight of15 ~17g; The peel is thick and dark red; The pulp is dense, with little juice, and the drying rate is 47%. Drought and barren tolerance, early fruit and high yield, poor self-flowering intensity, Zanhuang production areas are mostly equipped with spotted jujube as pollination trees. ② Fuping jujube. Also known as broken stove. Produced in Fuping, Hebei. Strong dryness, poor branching ability, short fruit branches, stable fruit setting and high yield. The fruit is large, oblong or cylindrical, and the average fruit weight is10 ~14g. The peel is deep red, the pulp is thick, the juice is less, the soluble solid content is about 26%, and the drying rate is 53.438 0%. Mature in late September. Suitable for drying, and can also be made into jujube and candied jujube. Drought resistance, barren resistance and saline-alkali resistance are very strong, and it is easy to crack fruit when it rains at maturity. ③ Junzao. Main production: Jiaocheng, Shanxi. The tree has great potential, moderate branching ability and high yield, but it is not stable. The fruit is large, cylindrical or obovate, with an average weight of 22.3 grams; The skin is thin, crimson, the meat is thick and crisp, the sugar content is 28.7%, it can be eaten fresh or dried, and the drying rate is 40%. Mature in the middle and late September. Cold, drought and waterlogging resistance. 4 pears and dates. Also known as big bell jujube and crisp jujube. Produced in northern Shandong, with the same name as Shanxi Lizao, both of them have the characteristics of early fruiting, high and stable yield. The difference is that the fruit of Shandong Lizao is smaller, with an average of15 ~ 20g; Shanxi pear jujube fruit is big and weighs about 30 grams. In addition, the pollen of the former is abortive, while that of the latter is normal. Both are early-maturing fresh food species. ⑤ Jujube. Henan Xinzheng, Zhengzhou, Zhongmou area. This tree is weak and productive. The fruit is large and rectangular, with an average weight of10.2g; The peel is medium thick and brownish red; The pulp is dense, the juice is less, the sugar content is about 30% and the drying rate is 43%. Both fresh food and dry food are used, and they mature in the middle and late September. Poor drought resistance. 6 jujube. Produced in Binxian and Changwu counties of Shaanxi Province. Strong trees, thick and hard branches, long life of jujube rootstock, high yield, but unstable. The fruit is very large, cylindrical or rectangular, with an average weight of 34 grams and a maximum of 60-70 grams, with irregular size; Peel thin, reddish brown; The pulp is crisp and tender, dense and juicy, with a sugar content of 28% and a drying rate of about 35%. Fresh food and dry food are both used, and they mature in late September. Strong ability to adapt to local conditions, but poor tolerance to barren land, like rich water. ⑦ Yiwu jujube. Zhejiang Yiwu, Lanxi and Yoichi Higashi. The tree has medium potential, strong dryness, medium branching ability, low self-flowering intensity, and high pollination yield of mixed jujube. The fruit is large, rectangular, with an average weight of 15.4g, red ochre, thin skin and thick flesh, loose texture, less juice and even sugar absorption, so it is an excellent variety for processing candied dates. In mid-August, Yiwu entered the white ripening stage of harvesting and processing. ⑧ Guanyang jujube. Also known as milk jujube. Guanyang, Jinxian, Lingui and other places in Guangxi. The tree is strong, with many flowers and many fruits, with an average of 2 fruits per jujube and high yield. The fruit is large, long and cylindrical, with an average weight of 14.3g: the meat is crisp, with a sugar content of 27.9% and a small stone. It is mainly used for processing candied dates, and can also be used for fresh eating and drying dried dates. From mid-August to early September, it turns red and mature. When the fruit is ripe, it will crack easily when it rains. Pet-name ruby winter jujube. Also known as frozen jujube and apple jujube. Produced in the northeast of the mountain, Cangzhou, Hebei, and Gucheng, the number is small. The tree is weak and open. The fruit is large, nearly round, slightly flat, with a blush on the sunny side, beautiful appearance, neat size, average single fruit weight 12.8g, thin skin, thick meat, tender meat, sweet and sour, and excellent fresh food. 65438+ 10 expires in the first half of the month.

jujube

The fruit is small, with an average weight of about 5 grams. The tree is weak, with a small crown and light leaves. Varieties are: ① Ziziphus jujuba. Location: Laoling, Shandong, Cangxian and xian county, Hebei. The tree is weak, the crown is small, the flowers are big, the fruit is good and the yield is high. The fruit is oval or obovate, with an average weight of 4-6 grams; The peel is thin and bright red; The pulp is dense and crisp, with sugar content of 34-38%, suitable for drying, and the drying rate is 55-58%, which is the best variety of dried jujube. Mature in the middle and late September. Saline-alkali tolerance, in the saline-alkali land with pH8.4 and total salt content of 0.3%, the growth and fruit are normal, but it is easy to crack when it matures in rain. ② Seedless jujube. Also known as hollow jujube. Mainly produced in Laoling, Shandong, Cangxian, Hebei, and planted sporadically. The branching ability is weak, the crown is sparse, and other characteristics are very similar to those of Jinsixiaozao. The fruit is oblong, with an average weight of 4.6 grams, red; Thin skin, thin meat, thin juice, few cores and soft. Mature in mid-September. Suitable for fresh food and drying. Like fat water, ripe fruits crack easily when it rains. ③ Ma Lian jujube. Produced in Zaoqiang County, Hebei Province. Jujube hangs for a long time, and the fruit setting rate is high. Each jujube hangs 2 ~ 3 fruits, which has strong high yield, adaptability and waterlogging tolerance. The average fruit weight is 4.4 ~ 8.3 grams, which is suitable for fresh eating and sun drying. 4 chicken heart jujube. Also known as Xinzheng jujube. Location: Xinzheng, Henan. Strong resistance, high and stable yield. The average weight of the fruit is 4.9 grams, and the meat is dense and juicy, suitable for drying, and the drying rate is about 55%. ⑤ Jishan jujube. Mainly produces Jishan and Xiangfen in Shanxi. This tree has great potential, early fruiting and high yield. The fruit is large, obovate, with an average weight of 8.9 grams, dark red skin, thick pulp and sugar content of 33.7%. Mature in the middle and late September, suitable for fresh food and drying. Not tolerant of salt and alkali, like fertile soil.

Key points of cultivation techniques

type

Grafting and ramet propagation are commonly used. Rootstocks are mostly autogenous rootstocks and Zizyphus jujuba, and there are also Cyclocarya paliurus as rootstocks. Copper coin tree is a deciduous tree belonging to Hemerocallis of Rhamnaceae, which has strong adaptability, easy reproduction, fast growth, developed root system and resistance to pests and diseases. The survival rate of jujube grafting is over 80%. But it is not cold-tolerant, and can be used in areas with abundant rainfall south of the Yangtze River. Xylem bud grafting, tongue grafting and cutting grafting are convenient to operate and have high survival rate. May-August is suitable for bud grafting, and April-September can be used for branch grafting.

get a first reign title after the founding of a dynasty

Jujube trees are mainly planted in wide rows and close density, with a general row spacing of 6-8m (jujube-grain intercropping12-20m) and a row spacing of 3-5m, which is appropriately changed according to terrain, soil, varieties and meteorological factors. It can be planted in spring and autumn, but it is very cold in winter, and the temperature in 65438+1October is lower than that in Yichun -8℃. Pollination varieties should be configured when planting, and the number of rows of pollinated trees should not be less than 1/4 of the main varieties.

Fertilization and irrigation

Base fertilizers, such as ring fertilizer, green manure, human excrement and urine, should be applied in time after jujube fruit is harvested, and applied in radial ditch or full garden ditch; Available nitrogen and phosphorus fertilizers can be applied 3 ~ 5 times a year. Water jujube trees during germination, flowering and young fruit drought, and pay attention to drainage in rainy season in low-lying areas.

Plastic trimming

The sparse layered and heart-shaped jujube trees have good light transmission and high yield. But pay attention to the fixed dry height of young trees after planting. The dry height of pure jujube orchard is 1 ~ 1.2 m, and the dry height of jujube-grain intercropping is1.2 ~1.4 m. Pruning jujube trees should be combined in winter and summer, and pruning in winter should be carried out before germination, which mainly includes: ① removing the vertical branches at the base of main and lateral branches and the vertical branches at the top of crown. (2) No secondary branch can be produced or the secondary branch is very weak when the jujube head with the length less than 30 cm is thinned; (3) Regeneration of fruiting branches through selection, bud cutting and retraction. With the growth of tree age, the pruning amount should be increased, and both winter and summer pruning should be paid equal attention.

Pruning in summer is usually carried out after germination and before the jujube head stops growing, mainly by thinning branches and removing the heart, and generally 1/3 of jujube head is cut off. Make the whole tree grow evenly, with moderate strength and transparent ventilation.

Old and weak trees are mainly updated and pruned. According to the updated light, medium and heavy, the main branches are retracted 1/3, 1/2 and 2/3 respectively to promote new shoots.

Jujube and grain intercropping

There is a habit of intercropping jujube and grain in jujube tree cultivation in China, but it is necessary to avoid the contradiction between fertilizer and water demand and realize the double harvest of jujube and grain. Experience around the world has proved that intercropping peanuts, beans and rape in jujube orchards is more beneficial.

Protect flowers and fruits

In order to improve the yield, in addition to meeting the ecological conditions such as temperature, moisture, light and soil, some measures can be taken to protect flowers and fruits: ① girdling, also known as opening nails. Generally, the girdling width of the trunk base is 0.3 ~ 0.6 cm in early June, which significantly improves the fruit setting rate. ② Spray water at flowering stage. Spraying water 2 ~ 3 times in the evening or morning at full flowering stage can obviously improve the fruit setting rate. (3) bees are released during flowering. ④ Spraying gibberellin (10 ~ 15 ppm) and borax at flowering stage is effective.

choose

Due to different uses, the harvesting period can be divided into three stages: white ripening, crisp ripening and complete ripening. Ethephon can speed up the harvest, and shake it manually or mechanically. Spread a cloth under the tree to prevent the fruit from being damaged.

Eliminate pests and diseases

1 jujube step. Also known as jujube inchworm. Larvae eat branches, leaves and buds, which often greatly reduce the yield of jujube trees, or even fail to harvest them. In autumn and winter, the jujube orchard is turned over to collect pupae, and the trunk is wrapped with plastic film to prevent female moths from laying eggs on the trees, and drugs are sprayed to kill larvae. ② Jujube armyworm. Also known as jujube moth. Larvae eat leaves and fruits. Scraping bark in winter to kill winter pupae, trapping and killing adults, and spraying medicine in larval stage. ③ Jujube witches' broom. This is a devastating jujube disease. In addition to removing diseased branches and trees in time, we should also pay attention to cultivating disease-resistant varieties. In addition, other diseases and pests of jujube trees should be actively controlled, such as moths, peach fruit borers, weevils, leaf lice, scale insects, jujube rust and so on.

economic value

Jujube is rich in nutrition. 100g fresh jujube fruit contains 400 ~ 600 mg of vitamin C, P3.358 mg of vitamin P, 0.2% of protein/kloc-0, 0.2% of fat and minerals such as calcium, phosphorus and iron. Besides being eaten fresh, jujube can also be processed into jujube, candied jujube, drunken jujube, jujube wine, jujube paste and jujube cake. You can also make dried dates, which are resistant to storage and transportation. Jujube is also an important traditional Chinese medicine, which has the effects of moistening the heart and lungs, relieving cough, nourishing the five internal organs, treating deficiency and eliminating stomach addiction; The pulp contains rutin, an effective component for lowering blood pressure. Jujube flowers contain a lot of honey and are the main nectar source plants. Wood is hard and fine-grained, which is the raw material for making furniture and handicrafts. This kind of jujube. ) it's beautiful and can be seen.

Jujube crane

The fallen leaves of jujube trees bear branches. Jujube hanging is the main part of jujube tree that bears leaves, flowers and fruits, and it is a dual-function organ of jujube tree photosynthesis and flowering and fruiting. It is slender, soft and drooping, so it is called jujube hanging (see figure). The hanging length of jujube varies with varieties and tree vigor, generally about 15 ~ 35cm, 10 ~ 25 knots; Uniaxial growth, few branches; The nodes are simply alternated, and the leaf order is1/2; Inflorescences and fruits are born in leaf axils without axillary buds. In the early stage of jujube hanging growth, the bud primordium in leaf axils differentiated into inflorescences, and a few differentiated into branches, which aborted halfway. How many dates hang on jujube branches, and a few grow on jujube heads, which occurs with the growth of jujube branches and jujube heads in spring and leaves fall off from the base in autumn. Due to the serious flowering and fruit dropping of jujube trees, many jujube pendants are flowering and fruitless, and a few jujube pendants have no inflorescences. (Li)

Jujube rootstock

The shortened fruiting mother branch of jujube (see figure). It is germinated from the main bud of the first branch of jujube tree and its secondary branch that does not fall off. In the second year, the main bud on the secondary branch is jujube rootstock. The annual growth of jujube rootstock is very small about 1 ~ 2 mm, and the length of 7-8 years is only10 mm. The terminal bud of jujube rootstock is a compound bud composed of a central main bud and several side buds. After germination in spring, the main bud extends forward slightly, and the secondary bud forms branching (jujube hanging). The life span of jujube rootstock can reach more than 10 years, and the fruiting ability is the strongest in 3 ~ 8 years. Jujube rootstock has 2 ~ 10 branches every year, and the number varies with the age of jujube rootstock and the strength of the tree. The rootstocks of old and new jujube trees grow weakly, and there are few fallen branches. Because of the long life and short length of jujube rootstock, the fruiting part of jujube is relatively stable. A few jujube strands can be bifurcated by lateral buds to form bifurcated jujube strands. Some jujube rootstocks grow vigorously due to the influence of nutrition or pruning, and their neck buds can also germinate into jujube heads.

kitchen range

Developmental branches of jujube. It is the basis for the formation of backbone branches and fruiting base branches (branches). In those days, jujube heads were composed of primary branches, secondary branches and tertiary branches (see figure).

The first branch is the axial branch of jujube head, and its length can reach 1 ~ 2 meters. There are terminal buds at the top; The 3 ~ 8 nodes at the base are leafless short nodes, and the fallen secondary branches have leaves on each node, and the axils of leaves often bloom, but most of them cannot bear fruit; Above the short nodes are long nodes, the number varies from a few nodes to more than a dozen nodes. Each node has leaves, the leaf order is 2/5, and it grows zigzag. Each node has a main bud and a secondary bud. The main bud does not germinate in the same year, and the secondary bud germinates into a secondary branch that does not fall off.

The secondary branches germinate and grow with the elongation of the primary branches, the number of nodes is 7 ~ 15, there is no terminal bud, each node has leaves, the leaf order is 1/2, each node has a primary bud and a secondary bud, the primary bud does not germinate in that year, and the secondary bud germinates into three branches.

The third branch germinates and grows with the elongation of the second branch, belonging to deciduous branches, generally with 10 ~ 25 nodes, and falls off at the same time as the leaves in autumn. In the following spring, the terminal bud of the first branch can generally continue to germinate jujube heads, while the main buds of other nodes germinate into jujube rootstocks or jujube heads, and some become hidden buds. Hidden buds have a long life and can germinate into jujube heads or rootstocks when stimulated. Most of the main buds of each node on the secondary branch germinate as jujube rootstocks, and a few germinate as jujube heads. Jujube head not only has the function of expanding crown and forming backbone branches, but also forms a large number of secondary branches, forming a large number of jujube rootstocks and increasing fruit-bearing parts.