Watermelon (Citrullus lanatus)is a melon crop of food and fodder value.
Depending on the purpose, they are divided into table watermelon and fodder watermelon.
Table watermelon fruits contain 6-12% sugars, 1-2% pectin, 1.5% fiber, vitamins B 1 , B 3 , B 9 , C, PP (folic acid), minerals (iron), citric acid, malic, succinic and nicotinic acids. The protein content is small, but it is represented by all the essential amino acids.
Table watermelon can also serve as a medicinal plant. Due to the content of iron, it is useful for anemia and anemia, liver disease, gastroenterocolitis and atherosclerosis, with metabolic disorders and insufficient blood circulation. One of the best
diuretics. Recommended for diseases such as nephritis, cystitis, constipation, overweight. Watermelon seeds produce an oil used to treat rickets.
The fruits are eaten fresh, used in the canning and confectionery industry for the manufacture of honey (nardek), candied fruits, molasses, marmalade, marshmallows.
Forage varieties of watermelon are used for livestock feed, they have a milk-producing property. 100 kg of fodder watermelon fruits correspond to 9-10 feed units and contain 40-200 g of digestible protein. For feed it is used fresh, ensiled and frozen. The fruits of fodder watermelon are characterized by good keeping quality.
Whip is also suitable for silage, usually in a mixture with corn , straw and sex crops and grass seeds. 100 kg of whips correspond to 19 feed units. 100 kg of silage from a mixture of watermelon and corn correspond to 13.5-14.2 feed units, contain 1.1-1.8 kg of digestible protein, from a mixture with straw – 12.5 feed units and 0.8 kg, respectively.
Table watermelon is one of the ancient agricultural crops that was known in ancient Egypt 4 thousand years ago. Later, watermelon began to be cultivated in the Arabian Peninsula, Palestine, Syria and Central Asia.
The place of origin is considered to be Central and South Africa, where it occurs in the wild.
In Russia, this culture was known in the VIII-X centuries. It was grown in the Volga region, but it became widespread at the beginning of the 17th century. Watermelon was cultivated as a greenhouse crop even in the northern regions, for example, in Moscow, Vladimir, Kazan, St. Petersburg.
Watermelon is grown in the Middle and Lower Volga regions, the North Caucasus, as well as in Ukraine and Moldova.
The yield of table watermelon on non-irrigated lands is 20-30 t/ha, on irrigated lands – 40-50 t/ha.
The yield of fodder watermelon is 30-60 t/ha.
Watermelon (Citrullus) is an annual plant represented by two species:
- table watermelon (Citrullus edulus Pang. (Lanatus));
- fodder watermelon, or candied fruit (Citrullus colocynthoides Pang.).
The root is taproot, highly branched, penetrates deep into the soil up to 1-5 m, spreads to the sides up to 7 m, and has a large suction capacity. The formation of the root system is completed in the flowering phase.
Stem creeping, creeping, long climbing up to 2-5 m, with 5-10 branches (up to 50), pubescent with stiff hairs, rounded-pentagonal.
The leaves are dissected into pinnatifid lobes, gray-green, stiffly pubescent, long-petiolate.
Flowers are quinary, yellow, dioecious, sometimes bisexual. The plant is monoecious. Cross pollination, with the help of insects (entomophilous). One plant can have up to 150 male flowers, female flowers are about 5 times less. The flowering of male flowers begins earlier than female ones.
The fruit is a multi-seeded false berry (pumpkin) on a long stem, spherical, oval or oblong, painted white-greenish or dark green, usually with a marbled pattern. The bark of the fruit is leathery, fragile, 0.5 to 2 cm thick. The pulp is of various textures, carmine-red, pink, sometimes white or yellow, tastes sweet or slightly sweet. The sugar content in the pulp is 5.7-13%. Fruit weight varies from 2 to 20 kg.
The seeds are flat, ovoid, 0.5-2 cm long, up to 10 mm wide, up to 3 mm thick, with a scar along the edge and a hard skin that has a white, cream, yellow, gray, red, brown and black color, sometimes spotted. pattern of various shapes. Weight of 1000 seeds 60-150 g.
The root system of fodder watermelon is more powerful than that of table watermelon, it penetrates into the depth of the soil by 2-5 m. With sufficient moisture in the upper soil layer, adventitious roots can form from the nodes of the lashes.
The stem is pentagonal, creeping, lashes up to 2-5 m long, strongly branched, pubescent with stiff hairs.
The leaves are deeply dissected, have larger shortened segments, rigidly pubescent.
The flowers are large, dioecious, with a pale yellow or yellow corolla. Male flowers are located on long pedicels, female – on short ones.
The fruits are from spherical to oval-oblong, green or light green in color with dark stripes of a marbled pattern, thick crust. The pulp is pale green, dense, unsweetened, sugar content 1.2-2.6%. Fruit weight from 10-15 to 25-30 kg.
Seeds without rib. Weight of 1000 seeds 100-200 g.
Table watermelon, in comparison with fodder watermelon, is more demanding on growing conditions.
Watermelon is a thermophilic and heat-tolerant plant.
In moist soil, seeds begin to germinate at a temperature of 15-17 °C, seedlings appear after 8-10 days. Seedlings die at a temperature of -1 °C.
The optimum temperature for the growth of stems and leaves is 20-22 °C, fertilization – 18-25 °C, fruit development – 25-30 °C. At temperatures below 15 °C, photosynthesis and growth processes are inhibited.
The sum of active temperatures above 10 °C is 2200-2500 °C.
Watermelon is a very drought-resistant plant due to its powerful developed root system, but it is responsive to irrigation.
Watermelon is a photophilous plant of a short day, does not tolerate shading.
Sandy and sandy loamy chernozem soils are optimally suited.
Loamy and clayey soils are of little use, as they firmly retain moisture and do not warm up well.
Optimal soil acidity pH 6.5-7.5.
Soil properties also affect fruit quality and fruit sugar content.
- first true leaf;
- 5-6 leaves;
- removable ripeness of fruits.
Under watermelon with deep autumn tillage, 15-20 t/ha of manure are applied . Higher doses may delay fruit ripening and reduce fruit quality.
For watermelon, it is recommended to apply N90P135K60 or separately N60P45K50 for autumn processing and N10P15K10 in rows when sowing. The introduction of mineral fertilizers increases the yield of fruits by 25-30%, the sugar content – by 2-3%. (Donetsk Vegetable and Melon Experimental Station).
It is also recommended to fertilize with N30P45K45 during the flowering phase.
Pre-sowing seed treatment
Warming up the seeds helps to increase the yield of watermelons by 11-20% (Donetsk vegetable and melon experimental station, Ukrainian research institute of vegetable and melon growing).
The optimal time for sowing watermelon seeds is when the soil temperature at a depth of 10 cm is 12-14 ° C. Seedlings appear in 9-10 days.
Recommended sowing schemes:
- 2.5×1.5-1.7 m;
- 2.1×2.1-1.4 m;
- 1.8×1.8-1.4 m.
The seeding rate is 1.5-3 kg/ha (2.3-4.6 thousand seeds/ha). The depth of sowing seeds is 6-8 cm. 1-2 plants are planted in one nest.
Cleaning of table watermelon is carried out in 2-3 steps as it ripens, fodder – in one step, before the onset of frost.
Signs of ripening watermelon fruits are drying of the stalk, coarsening of the bark and the appearance of a clear pattern on it.
When harvesting watermelons on fruits, it is recommended to leave the stalks for better keeping quality.
During the last continuous collection of watermelon fruits, one-time harvesting for seeds, it is economically justified to mechanized collection of fruits into swaths using a УПВ-8 swather, followed by the selection of swaths by a ПБВ-1 picker and their soft laying in vehicles. The technology reduces labor costs by 5-8 times compared to harvesting fruits with the removal to the side of the field.
Undamaged fruits are suitable for storage. The storage temperature of watermelons is 2-3 °C and the maximum air humidity is 75-85%.
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V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
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