Characteristics: watermelon main root system, the main root depth of more than 1 m, the root group is mainly distributed in the 20 cm - 30 cm of the cultivated layer, the root is slender and easy to break, regeneration is weak, intolerant of transplantation. Seedling stems are erect, elongating between 4 - 5 nodes, creeping growth after 5 - 6 leaves, strong branching, can form 3 - 4 levels of lateral branches. Leaves alternate, y lobed, lobed and entire. Dioecious and monoecious, male flowers appear at nodes 3--5 of the main stem, female flowers at nodes 5--7, and a few hermaphroditic flowers may appear at the peak of flowering. Corolla yellow. Ovary inferior, lateral membranous placentation. Both male and female flowers are nectarous, insect-mediated flowers, flowers open early in the morning and close in the afternoon. Fruits are globular, ovoid, ellipsoid, cylindrical, etc. The surface of the fruit is smooth or furrowed. The surface of the fruit is smooth or furrowed, and the epidermis is greenish-white, green, dark green, dark green, black, with fine reticulation or stripes. The flesh is creamy white, light yellow, dark yellow, light red, big red and other colors. The flesh is divided into tight flesh and sandy flesh. Seeds are flat, ovoid or long ovoid, smooth or cracked. Seed coat white, light brown, brown, black or brown, monochromatic or mixed colors. Seed weight per thousand is 100g--150g for large-seeded types, 40g--60g for medium-seeded types, and 20g--25g for small-seeded types. Seed melon type 150 grams - 200 grams.
Cultivation Watermelon likes high temperature and dry climate. Growth temperature of 25 ~ 30 ℃, 6 ~ 10 ℃ when susceptible to cold damage. The average monthly temperature of 19 ℃ above the month of the year more than 3 months of the region is feasible for open field cultivation. Is a long day plants, like strong light, light saturation point of 80,000 lux. Suitable for hot and dry climate, strong drought tolerance, requires well-drained, deep sandy loam soil. Soil pH 5-7 is suitable. China's watermelon cultivation in a variety of ways. The open field ones are dry pond cultivation and sand field cultivation in Northwest China, flat bed cultivation in North China, and raised bed cultivation south of the Yangtze River, etc. The protected field ones are windbreak cultivation in Beijing, reed hair cultivation in Baoding, as well as ground film cover cultivation, plastic greenhouse cultivation and greenhouse cultivation, etc. Whether it is open field or protected field cultivation, the cultivation of watermelon can be done in a variety of different ways. Regardless of the open ground or protected cultivation, are in the spring first protected seedlings, and then planting. Base fertilizer to organic fertilizer, with calcium superphosphate and potassium sulfate can improve the sugar content of the fruit. Planting density is generally mu planted 500 to 600 plants. North China rows rectification, a plant a vine a melon; South China does not rectification, a plant more vines more melon. From sowing to harvesting about 80 to 120 days, from the female flowers open to fruit ripening about 30 to 50 days. The main diseases are blight, anthracnose, powdery mildew, etc. The main insect pests are aphids, seed flies, and melon guards.
Origin Most of the country can be cultivated. There are a lot of cultivation in Laixi, Shandong Province, and the Nanlan watermelon produced in Hetoudian Town of Laixi City is famous for its sandy flesh, sweet flavor, much water and rich nutrition.
Use Watermelon fruit is the main fruit in summer. In addition to the large amount of water contained in the mature fruit, the sugar content of the flesh is generally 5 to 12%, including glucose, fructose and sucrose. The sweetness increases with the increase of sucrose in the late ripening stage. A few do not contain starch, and the sweetness will be reduced due to the hydrolysis of disaccharide to monosaccharide during postharvest storage. Melon seeds can be used as tea, melon rind can be processed into watermelon sauce. In Chinese medicine to melon juice and melon rind into medicine, function of summer heat relief.
Also known as summer melon, cold melon, known as the king of melons, because in the Han Dynasty when introduced from the West, so called watermelon. Watermelon also belongs to the cucurbitaceae annual herbaceous plants, native to Africa, in addition to a few remote cold areas, all over the country are planted, the fruit taste sweet and cold.
Watermelon is the typical fruit of summer, but also the main fruit of summer, we should cherish more.
In the hot summer days or sweltering tropical night, as long as there is a frozen watermelon, it will have the effect of eliminating the summer heat.
Varieties: watermelon to use different, can be divided into three categories: ordinary watermelon, melon melon, small watermelon
China is the world's largest producer of watermelon, but the watermelon did not originate in China. The native place of watermelon is in Africa, it was originally a wild plant of the cucurbit family, and then artificially cultivated to become edible watermelon.
As early as four thousand years ago, the Egyptians planted watermelon, and then gradually moved north, initially by the Mediterranean coast to northern Europe, and then south into the Middle East, India and other places, the fourth and fifth centuries, by the western region into our country, so it is called "watermelon".
According to the Ming Dynasty scientist Xu Guangqi, "Agricultural Politics Book" records: "watermelon, planted out of the West, so the name." Ming Li Shizhen in the "Compendium of Materia Medica" recorded: "According to Hu Jiao in Huihe got melon seeds, the name is watermelon. The watermelon since the Five Dynasties when it began to enter China; now both north and south." This shows that the cultivation of watermelon in China has a long history.
How to get seedless watermelon
Now the production of cultivated seedless watermelon, are triploid (3X) watermelon. It is by the tetraploid (4X) watermelon as the mother, diploid (2X) watermelon as the father for hybridization and generation of hybrids. Currently cultivated seedless watermelon is not completely without seeds, there are undeveloped like young cucumber seeds like a small and white seed coat, eat the feeling of seedless, so called seedless watermelon.
Other methods of producing seedless watermelon
1. natural hormone method
This method is based on the watermelon has a "unisexual fruiting" characteristics, the use of fewer seeds (tetraploid) watermelon flowers contain natural hormones, stimulate diploid watermelon seeded ovary, so that it does not occur in the process of fertilization, but through its internal physiological role, to promote the normal (diploid) seeded watermelon. Through its internal physiological action, the common (diploid) watermelon plant is prompted to sit and grow into seedless watermelon, which is a new way to rapidly produce seedless watermelon. It has the characteristics of easy to take materials, simple methods, convenient operation, etc., can produce seedless watermelon that year, and the fruit type is upright, thin skin, not hollow, the texture and flavor of watermelon is the same with the original common watermelon varieties, from growth to maturity without special cultivation measures, to avoid the low germination rate of the seedless watermelon, the low rate of seedling and the low rate of fruition and other problems.
Hubei Provincial Academy of Agricultural Sciences has proved over the years after many tests, the use of the method of production of seedless watermelon, and triploid seedless watermelon similar to the fruit contains only white edible blighted seeds, no hollow, enameled up to 9% to 10%, the thickness of the rind and flavor are the same as the ordinary watermelon varieties selected. Test results, to choose Xingcheng red as the mother of the production of seedless watermelon is the best, the performance of thin skin, crisp sandy flesh, high sugar content, good flavor, small and few white seeds. Honey Bao, all three watermelon as the mother of the production of seedless watermelon, the specific production technology points are:
(1) choose a good parent: selected as the father of the less seeded watermelon, the number of seeds in the fruit required, pollen quality of good varieties, and the requirement of robust plant growth. Selected as the mother of the ordinary watermelon, the number of seeds in the fruit should be less, the fruit skin is thin, high sugar content, good quality varieties, and requires robust plant growth.
(2) timely pollination: the male flowers selected as the parent and the female flowers selected as the parent should be bagged or artificially girdled for protection in the afternoon of the day before flowering. The next morning when the male and female flowers open, remove the male flowers in time, remove the bag or girdle, the female flowers for artificial pollination, pollination should be fully and carefully carried out, so as not to damage the female flowers. After pollination, the female flowers are still bagged or girdled to prevent the pollen of common watermelon from falling onto the stigma. Generally 3 days after pollination, young melon sitting that should be promptly removed from the bag to promote the normal growth and development of young melon.
(3) get rid of shaped melon: in the use of natural hormones to produce seedless watermelon in the melon field, the melon to stay in the melon field after sitting, timely removal without artificial pollination and naturally sitting melon, to prevent the production of shaped melon and seeded watermelon. Otherwise, due to the strong competitiveness of ordinary watermelon, hormone watermelon growth competitiveness is weak and cause young melon growth or melting melon.
(4) strengthen fertilizer management: due to the natural hormone stimulation and the generation of seedless watermelon is unfertilized embryo growth, so its growth and development is relatively fragile, must be given a good fertilizer conditions and to strengthen the finishing work of the vines, in order to promote its normal growth and development.
(5) timely harvesting: the use of the method of production of seedless watermelon, medium-maturity varieties of the appropriate harvesting period for about 30 days after flowering, harvesting too early, sugar content is not high, poor quality; harvesting too late, the blight within the fruit increases, affecting the taste. Seedless watermelon after harvest should be sold or eaten immediately, not easy to store for a long time, otherwise the fruit within the blighted seeds harden, quality deterioration.
2. synthetic hormone method
Practice has proved that the use of certain hormone substances for artificial induction, can also make ordinary diploid watermelon watermelon, and the knot into a watermelon, but also only with the embryo of the white tender seed coat, eat as seedless watermelon. Specific production points are:
(1) Selection of good varieties: test proved that the early flower is the current use of synthetic hormones to produce seedless watermelon varieties, in other measures when the right time, the rate of seedless watermelon up to 90%, and the varieties of artificial pollination of seeded watermelon produced by artificial pollination of watermelon rate is basically the same. Other varieties such as Zhengzhou 3, Le honey 1, in the breeding 6, Lu watermelon 1, etc. is also better.
(2) treatment method: first with distilled water with 100 ppm of sodium naphthalene acetic acid, 25 ppm of gibberellin and 25 ppm of 2,4 ~ D and other three solutions. Then use these three solutions of equal amount of mixing solution (mixing ratio of 1:1:1) to deal with watermelon female flowers. The mixing solution is required to be used as needed, and the mixture is used up on the same day. Treatment of female flowers of Wanfa is, in the afternoon before the opening of female flowers first bag or clip flowers to protect (such as hermaphroditic flowers should be strictly de-male), the next morning when the female flowers are open, remove the bag or restraints, with a new brush dipped in the mixture coated with the stigma of the female flowers and the base of the ovary, the amount of each flower per dosage of about 1 milliliter. The corolla must still be clamped or bagged for protection after application. Remove the bag on the fourth day after applying the drug and apply the mixture once, or apply a 20 ppm solution of cytokinin 6 ~ furanaminopurine, to improve the rate of melon formation are with obvious effect. Tests have proved that the main vine (double vine branching) the second female flower treatment is the most ideal. Coating should choose a sunny day, such as coating rain, rain should be re-coated 1 time.
(3) Fine field management: The plants should be strong before flowering. After the drug treatment, it is necessary to pinch off the main vine leaf axils of the lateral vines and growth points, and press the melon vines, to promote nutrient delivery to the melon. Coated with the first drug, such as the discovery of young melon skin color dark, to supplement the coating 1 time, can effectively prevent the melons. About 10 days after the first coating treatment, you can pinch off the growth point of the second melon vine. Don't keep the untreated young melon on the two vines of the same plant, because the seeded melon and seedless melon at the same time on a plant, the nutrients are easily competed by the seeded melon, and cause the seedless melon to melt melon. Other female flowers should be removed in time to prevent seeded melons from sitting. About 12 days after the first coating treatment, reaching the safety period, watering and fertilizer should be carried out. However, the amount of watering should not be too large, in order to small watering is appropriate, generally each time each mu watering 3 to 4 cubic meters can be, every 2 to 3 days watering. Fertilizer should be applied in a furrow on one side of the plant, 30 to 40 kilograms of three yuan compound fertilizer per mu.
3. Cultivation of cuttings
See the section "Cultivation of cuttings" for details.
4. Tissue culture method
Tissue culture is the use of a part of the plant tissues or organs in sterile conditions, cultivated into a complete plant a new method of reproduction. Our country from 1979 that began to carry out this work, at present, Shanghai, Beijing, Shandong, Hebei, Shanxi, Gansu and Heilongjiang and other provinces and cities of many units have been used to produce a large number of high-quality, high-yield seedless watermelon supply market, and achieved significant economic and social benefits. Specific methods are:
(1) culture materials: according to domestic and foreign reports, watermelon seed embryo, stem tip, root tip, pollen and ovary, etc. can be used for tissue culture, but at present the most used is the seed embryo and stem tip tissue culture.
(2) culture medium: watermelon tissue culture culture medium selected materials and culture stage of different different. Generally can be divided into bud mass differentiation medium, seed embryo medium and rooting medium and so on three kinds.
①Watermelon bud group medium: per liter of medium with large elements of ammonium nitrate (NH4NO3) 500 mg, potassium nitrate (KNO3) 1000 mg, calcium chloride (CaC12) 440 mg, magnesium sulfate (MgSO4-7H2O) 370 mg, potassium dihydrogen phosphate (KH2PO4) 370 mg, iron salt EDTA-Na2) 745 mg; with trace elements of sulfuric acid, potassium phosphate (KH2PO4) 370 mg. milligrams; there are trace elements ferrous sulfate (FeSO4-7H2O) 55.7 grams, manganese sulfate (MnSO4-4H2O) 22.3 milligrams, boric acid (H3BO3) 6.2 milligrams, potassium iodide (KI) 0.83 milligrams, sodium molybdate (Na2MoO4-2H2O) 0.25 milligrams, zinc sulfate (ZnSO4-7H2O) 8.6 milligrams, copper sulfate (CuSO4-5H2O) 0.5 milligrams. CuSO4-5H2O) 0.025 mg, cobalt chloride (CoC12-6H2O) 0.025 mg; containing organic matter inositol 100 mg, vitamin B10.4 mg, vitamin B60.5 mg, glycine 2 mg, niacin 0.5 mg; containing the hormone indole acetic acid (IAA) 1 mg, 6-benzyl purine (6-BA) 0.5 mg; containing agar 7 g Sucrose was changed to 20 grams per liter (33.3 grams of white sugar). pH was adjusted to 6-6.4.
③Watermelon rooting medium: in addition to ① hormone 6-benzylpurine and indoleacetic acid removed, replaced with indolebutyric acid (IBA) 1mg, the rest of the various types of elements and ① exactly the same.
(3) Cultivation method: first of all, the culture material is sterilized. If the material is taken as seeds, first soak the seeds in 70～80℃ warm water, stirring to about 30℃, soak for one day and night, then sterilize with 75% alcohol for 30 seconds, peel off the seed coat under aseptic conditions, sterilize with 0.1% open mercury for 2 minutes, and then rinse with aseptic water for 4～5 times, inoculate on the medium, and put it into the cultivation room for cultivation. The radicle sprouted first, and when the 2 cotyledons unfolded and turned green after 2 weeks, the radicle with cotyledons was cut for transfer culture. Later, the terminal and lateral buds were separated by cutting every 3 to 4 weeks, and then succeeded to culture.
If the stem tip or lateral buds are taken directly from triploid watermelon seedlings in the field, the material taken should be rinsed with tap water, then sterilized with 75% alcohol for 10 seconds, then sterilized with 0.1% mercuric acid ascension for 2 bells, and finally rinsed with sterile water for 4-5 times, inoculated on the medium, and put into the incubation room for cultivation.
(4) Medium and culture conditions: The basic medium used was M5 and 1/2MS, with different hormones attached according to the specific requirements for different aspects of seedling differentiation, growth and rooting, plus 3% sucrose, 0.7% agar, and pH adjusted to 5.8. Autoclave the plants at a pressure of 1 kg/cm2 for 20 minutes, and then carry out the inoculation, and then inoculate the inoculated explants at a temperature of 26℃. The inoculated explants were cultured in a culture room at a temperature of 26±1°C, light intensity of 1000 lux, and light illumination of 14 h/day.
(5) Grafting and management: The shoots proliferated by tissue culture can be directly cultivated into seedlings for production or grafted and cultivated into grafted seedlings for production, with the latter being preferred. If cultivating grafted seedlings, the differentiated sprouts need to be heightened before grafting. The method is to transfer the sprouts to agonist-free MS+IBA0.5~1.0+GA0.5 rooting medium, so that the base of the sprouts gradually rooted, along with the growth of the roots, the young stems are rapidly heightened, robust development, and improve the quality of the scion. The rootstock used for grafting was sown in a plastic nutrient bowl containing ordinary soil, and the rootstock terminal bud was removed for grafting when the cotyledons unfolded and the true leaves were slightly exposed. The selection of rootstocks and grafting operation methods refer to the "grafting cultivation" section. Immediately after grafting into the healing shed healing, shed temperature 25 ~ 35 ℃, relative humidity of 95% or more, under these conditions, the grafted seedlings can generally be healed in about 10 days, and then transferred to the greenhouse, exercise 3 ~ 4 days. Attention should be paid to air ventilation during this period, so that it will gradually enhance the adaptability. Finally transplanted to the field. Field cultivation and management measures are similar to those of seedless watermelon cultivation and management measures.
When was watermelon introduced to China
Watermelon, native to Africa. Egypt has been cultivating watermelon for five or six thousand years. In the past, some people cited the Song Dynasty Ouyang Xiu "New Five Dynasties History - four barbarians appendix," said: five generations of Tongzhou Heyang County, the highest peak of the Qidan "began to eat watermelon", "Qidan broke the Huihe to get this kind of cow dung covered with trellises and planting, as big as China's winter melon and the taste of sweet", "Zhou Guangshun three years (three years) (the first two years of the Zhou Guangshun). "Zhou Guangshun three years (953) ...... highest peak return". Thus, the watermelon from the Five Dynasties by the Western region into China, seems to have become the final word. In recent years, the newspaper articles talking about watermelon more than this statement. 1981 Hunan People's Publishing House published extracurricular reading material for secondary school students, "food, clothing, housing and transportation history" in the "watermelon began in the Five Dynasties" section. In fact, this statement is not accurate.
Ming Dynasty Li Shizhen in the "Materia Medica Compendium" pointed out: watermelon is also known as cold melon. "Tao Hongjing (North and South Dynasties) note melon tip that Yongjia (Jin Huaidi year number) has a cold melon is very large, can be hidden until the spring sound, that is, this is also. Cover five generations of the first melon species has entered zhejiang east, but no watermelon name, not all over China." Southern History - Teng Tanguong biography, said Tanguong "five years old, his mother Yang's fever, want to eat cold watermelon, the local custom is not produced. Teng Tanguong visited all the time can not get, articulated sadness and grief. Then, he met a sangmen who asked him the reason, and Tanguang told him everything. He said, 'I have two melons, so I will leave you one of them. Returned with the mother, the room was surprised, looking for the door, do not know where". Tang Dynasty Duan Chengshi's "Youyang Miscellany Chopping Block" Volume 19 records the Hidden Marquis (Shen Yao) of the "line garden" poem: "Cold melon square lying ridge, autumn bushes are full of pei. The purple eggplant is a firm favorite, and the green taro is all over the place." From the poem about the cold melon lying in the ridge of the season, is consistent with the watermelon. In addition, the old Beijing had said that the first listing of watermelon as "watermelon", after the listing of the "cold melon"; today, I visited the old farmers, also said that the late watermelon is indeed "cold melon" a name. It seems that the above literature can be corroborated with Li Shizhen's statement. However, Li Shizhen's claim over the centuries does not seem to have attracted attention. 1976, Guangxi Guixian Western Han Dynasty tomb coffin room sludge was found in watermelon seeds; in 1980, Jiangsu Province, Yangzhou, western suburbs of Ganjiang County Han Tomb buried in the lacquer watermelon seeds, the owner of the tomb died in the first three years of Emperor Xuandi of the Han Dynasty (71 years ago). This irrefutably proves the reliability of Li Shizhen's record.
Watermelon, as its name implies, is a melon that came from the West. Before the Five Dynasties, since it has been introduced to China's southeastern coastal areas, but not called watermelon, but because of its nature of cold to relieve heat, called cold melon. Therefore, the watermelon is from the Western region of China's claim seems to be questionable. Then, it is from what route into China?
The author speculates that it is by the "Maritime Silk Road" into China. Emperor Wu of the Han Dynasty had sent "translation of the long", collect merchants and people, with silk, by sea to the Western countries "city pearl, Bili displaced, strange stone, foreign objects. Sea ship from the Leizhou Peninsula sail, along the west coast of the Gulf of Tonkin and the coast of Vietnam sailing, around the southern tip of Vietnam Maujiao, and then along the Gulf of Siam, along the coast of the Malay Peninsula south to Singapore, and the west fold, across the Strait of Malacca, along the Bay of Bengal to reach has been Cheng not the country, "Han's interpretation of the make since then also carry on" ("Han Shu - Geography Zhi"); this sea, the sea road, is the so-called "Maritime Silk Road". This is the so-called "Maritime Silk Road".
What is the place of today, most scholars believe is Sri Lanka, and some say it is Abyssinia in eastern Africa. Whichever is right, it shows that the sea route for transportation between China and Africa had been opened in the era of Emperor Wu of Han Dynasty. Because in the Han Dynasty, the Arabs had mastered the secret of the trade winds in the Indian Ocean and were able to sail east and west through the Indian Ocean. In this way, it is entirely possible that Sri Lanka and the Southern Ocean Islands could have become a transit point for transportation between China and Africa. Watermelons from Africa could have passed through Sri Lanka or the Nanyang Islands before being introduced to China. Watermelon seeds unearthed from Han tombs in Guangxi and Jiangsu are evidence that the Maritime Silk Road bridged cultural exchanges between China and Africa.
Additionally, according to the February 24, 1959 Guangming Daily, watermelon seeds have been found in the Neolithic site of Shuitianfan in Hangzhou, Zhejiang Province. If this archaeological harvest is indeed reliable, China has a history of watermelon at least four thousand years, and watermelon originated in Africa, another story.