Cultivation techniques of 8482 unicorn melon
Second, border field preparation and fertilization
(1) Sow Gua Tian in spring. Before winter, we should plough deeply for 20-30 cm, only plough without harrowing, and freeze in the sun, which is beneficial to soil weathering, freezing injury, snow accumulation and moisture storage. In early spring, borrow soil moisture as appropriate and rake it flat. Then, according to the cultivation method, it is planned to dig melon ditch (also called high-yield ditch). Digging melon ditch can thicken active soil layer, promote root extension and facilitate centralized application of base fertilizer. Guagou is mostly east-west and arranged north and south. According to the line spacing of 1.6- 1.8m, dig a trench with a width of 50-60cm and a depth of 40cm, with a 20cm meter on the south side and a bottom on the north side of the trench.
(2) Watermelon with basal fertilizer has lush stems and leaves, short growth period, high yield and large fertilizer demand. Sufficient base fertilizer must be applied to provide basic nutrients for the whole growth period of watermelon. Especially in plastic film mulching cultivation, topdressing is inconvenient, such as insufficient base fertilizer, which is easy to cause premature senescence of plants and affect fruit development. The base fertilizer is mainly long-acting organic fertilizer, and then an appropriate amount of chemical fertilizer is added. 1. Fertilization amount depends on soil fertility. 3000-5000 kg of high-quality manure or cake fertilizer 150-200 kg can be applied per mu in the middle and lower parts. For plots with good fertility, 2000-2500 kg of manure or cake fertilizer 100 kg can be applied. The soil in suburban counties of our city is generally short of phosphorus and the sand is short of potassium, so the proportion of phosphorus and potassium fertilizer should be increased. For example, 50-70 kg of calcium superphosphate and 10- 15 kg of potassium sulfate can be added per mu. 2. The base fertilizer application method can recover most of the coarse fertilizer before winter ploughing, leaving a small part of high-quality coarse fertilizer mixed with all the cake fertilizer for fermentation and decomposition, concentrated in melon ditch. Part of the topsoil on the south side of the ditch is mixed with fertilizer and applied into the ditch, and then the remaining topsoil is reduced and leveled.
(3) making a watering and film-covering frame; Management, etc. Need to make a suitable bed. 1, high ridge horizontal ridge 2, furrow ridge horizontal ridge (hole ridge horizontal ridge) 3, wave ridge 4, sawtooth ridge l, 3 are suitable for clay or clay loam 2, 4 are suitable for sandy soil or sandy loam.
[/pre][pre] (4) Water along the ditch 2-3 days before sowing. The amount of water should be adequate and not excessive, so as to avoid fertilizer loss.
Third, seed selection and seed treatment
(1) Selecting excellent varieties is the premise of high yield and high quality. At present, excellent varieties suitable for production in our city are: Zhengza No.5, No.7, Shuangxing ll, Xin Jing 1 and so on. Early maturity and medium maturity; Zhongyu 6, Fengshou 3, Jinhua Bao (Pz), Jinzhong Guanlong and Xinyou 2 in Guanlong series; Late-maturing Xinhongbao, Xinhongbao Series Jubao 1, Huaxia Xinhongbao, etc. Can be purchased according to the variety specifications of the sales unit and local cultivation conditions. Impurities and impurities of the selected varieties should also be strictly eliminated, and seeds with shriveled grains, miscellaneous grains and moldy grains should be detected to facilitate the vigorous development of buds.
(2) Before disinfection, melon farmers scalded their seeds with hot water, because the temperature and time were not well mastered, which was not suitable. The applicable methods are: 1. Soak the seeds in warm soup. 55℃ warm water (two open and one cool), the amount of water is 5-6 times of the amount of seeds, soak the seeds for 30 minutes, stir while soaking, and naturally cool. Don't use aluminum pot, in case the water temperature drops too fast, which can't achieve the purpose of disinfection. After 30 minutes, soak in cold water at 20℃. 2. Sterilize the seeds with warm soup. Soak the seeds in cold water for 2 hours or dry them in cold water for 4 hours, and then disinfect the seeds with drugs. (l) Soak the seeds in formalin which is 0/00 times of/kloc-0 for 0/0 minute, and then rinse them with liquid medicine several times. It can kill Fusarium wilt and anthracnose on seed coat. (2) Seed soaking with 10% sodium phosphate solution for 20 minutes can kill the virus. (3) Soaking seeds with 2%-4% bleaching powder solution for 30 minutes can kill germs.
(3) Soak the sterilized seeds to accelerate germination, soak them in water at 20℃ for 6- 12 hours (depending on the thickness of seed coat), wipe off the mucus with a towel, wrap them with a wet cloth, and accelerate germination at 25-30℃. Generally, 1-2 days later, the seeds are "exposed". Check the temperature and humidity frequently. When rinsing water, the water temperature is 30℃; The heat source for accelerating germination can be electric mattress, soil temperature box and fire resistance. With the help of human body temperature, it is safer and more reliable to carry around. The "exposure" of seeds is less than 3 mm, and too long will affect sowing. Some "exposed" seeds of 2-3 mm should be picked out in time and placed at room temperature of 65438 05℃ to inhibit elongation and make them stout. When 80%-90% of the seeds germinate, they can be planted.
Fourth, sow seeds.
(1) The standard of sowing date in the open field is 10 cm, the ground temperature is stable above 15℃, and the final frost has passed at the time of emergence, which is a safe sowing date. The suburban counties of our city are generally on April 20th 15. If the single film mulching is flat, the sowing can be delayed for 2-3 days. If the plastic film ditch is empty, 0 to 2 seedlings with real leaves will grow under the film, and the sowing date can be half a month earlier than that in the open field. If the small shed is covered with plastic film, it is suitable to sow in the middle and late March. Seedling raising in sunny beds can be sown in early March, transplanted and planted in early April, and covered with a small bow shed. Wheat interplanting should be on May 20-25. Summer sowing of wheat stubble should be in July 15-30 to avoid the early rainy season.
(2) Planting density Watermelon planting density varies with varieties, cultivation methods, management level and soil fertility. Only 300—40O plants should be planted thinly and 2000 plants should be planted densely per mu. The density can be determined from the following aspects: 1. According to varieties, the weak and early-maturing varieties are per mu 1000 plants. There are about 800 medium-mature tree species with vigorous growth per mu. Late-maturing varieties of big melons can be planted with 500-600 plants/mu. 2. According to the cultivation method, it is decided that the cultivation in the open field should be sparse rather than dense. Cultivation in protected areas should be closely planted. The purpose is to make full use of land, space and growth time and improve economic benefits. 3. According to soil fertility and management level, it is determined that thin land should be dense and good land should be sparse. If the management level is high and the labor force is sufficient, it can be planted closely, and vice versa. 4. At present, foreign countries take low-density measures, give full play to the advantages of individual plants, produce more melons and improve yield and quality. For example, Japan only breeds 1 10 plants per mu, with only 300 plant heights, 370-400 plants cultivated in greenhouse, and 144 plants cultivated in open field in the United States. These situations are for reference only.
(3) The sowing method is generally ditch sowing, which requires fine soil preparation and sufficient soil moisture. Shallow furrowing and deep mulching should be adopted for sowing through film in the open field. That is, the gully is 2-3cm deep, 3-4cm wide and12cm long. If the soil moisture is insufficient, water is needed. 4 seeds per hole, 3 cm apart. The seeds lay flat at the bottom of the ditch with the buds facing down. Don't sow upright, so as not to bring out the seeds with shells. After sowing, cover with wet cheese and press gently. Cover another small mound and pat the surface steady. After 4-6 days, when the buds bend their necks, the mounds are removed and the seedlings can appear. Sow first, then cover with plastic film, do not cover the mound, and the sowing depth should not exceed 2 cm. The seeds that accelerate germination should be planted in different grades according to the bud length, so that the emergence of seedlings is neat and consistent.
5. The application of plastic film mulching technology began in Japan and was introduced to China in the late 1970s. Therefore, this technology is simple, mature early, increase production and income, and is well received by melon farmers. 1986, more than 50% of the land in Gua Tian of northern China was covered with plastic film. At present, it has become a conventional technique for early-maturing cultivation. Watermelon planting in spring has been basically covered with plastic film.
(1) There are two kinds of mulch film: colorless transparent film and colored film. At present, the thickness of common high-pressure polyethylene film is 0.015-0.02 mm. In recent years, 0.007-0.009mm ultra-thin film, wheat field interplanting and summer sowing have been popularized. Silver-gray film is used to prevent aphids, and black silver-gray two-color film is used to prevent weeds.
(2) The film covering method is 1. In general, the film is laid flat on the whole flat ridge or high ridge. Then the membrane is tightened and flat as a mirror, and the four sides are ditched and buried, compacted and sealed. 2. The improved method (ditch-hole empty cover method) is improved on the basis of the common method. (l) Empty hole cover: Cover the holes and ridges on the plane with film, and narrow film can be used. The cave is 5 cm deep and 10- 12 cm in diameter. Before pulling out the cross, the seedlings grow in the hole. (2) Ridge and furrow covering: cover the ridge and furrow with a film with a width of 90- 100 cm, without covering the border. The ditch is 7-8cm deep, 0/5-20cm wide and 7-8cm high. The height from the bottom of the ditch to the membrane is 12- 14 cm. Four true leaves of the seedling once grew in the ditch. In order to prevent membrane jumping, a layer can be placed in the ditch every 3-4 plants to make the membrane dense, which is called ditch-hole combination. 3. Sunward type, such as sawtooth type, covers the film into sunny slope, making the film into a miniature sun room. But you need to put a strip under the film every 40-50 cm. 4. The small arch-shed covering (also known as the ceiling-shed covering) is inserted into a small arch back with purple spikes or bamboo pieces, with a height of 25-30 cm and a width of 50 cm, and one is inserted every 40-50 cm. The upper membrane is in the shape of an arched shed, and the seedlings grow in the shed until they are clustered or elongated. (3) Plastic film coverage requirements 1. Plastic film has narrow coverage width, small coverage area, low efficiency of warming and moisture conservation, and excessive investment, resulting in waste. Generally, 60-80 cm ultra-thin film or universal film should be used. The improved ditch cover and anode cover adopt 80- 100 cm universal membrane. General membrane should be adopted for small bow shed, and the width is 100- 120 cm. 2. The film covering operation must be smooth and tight, and the film edge should be buried, compacted and sealed. Try to keep the film surface intact, clean and large in light receiving area. The damaged membrane should be repaired in time.
Intransitive verb Tian Tuan management
(1) Seedling management focuses on protecting seedlings and cultivating strong seedlings, and different cultivation methods have their own emphasis. 1. The emphasis of spring sowing in open field cultivation is to preserve soil moisture, raise ground temperature, carefully cultivate the soil before breaking the heart, and promote rooting. When the true leaves of 1 are unfolded, the seedlings should be fixed and strong. When the true leaves are spread (pulled horizontally), apply seedling fertilizer in the ditch. Apply 2-3g urea and 2-3g diammonium to each plant. Pay attention to the weak seedlings, 8- 10cm away from the seedlings, not too concentrated, to avoid burning the seedlings with fertilizer. Water it properly. 4-6 When leaves really grow, it is necessary to look at the seedling situation, skillfully fertilize the trees and water them properly. Deep intertillage is generally used for weeding once or twice in the field. It is not suitable to plough the pier early when trapped trees, and intertillage and loosening the soil will not hurt the roots. 2. Common plastic film cultivation, timely plastic film seedling raising, fixed seedling raising time and early prevention and control of underground pests are the key points. Pay attention to the weather forecast, put seedlings to prevent cold, and generally do not topdress or water at seedling stage. 3. Improved, sunny and shed-covered cultivation should focus on outdoor exercise, pest control and weeding, and generally do not water at seedling stage to prevent pole jumping. Outdoor exercise can be started when the temperature in the film exceeds 35℃ after emergence. The improved type and the positive bed type should be opened above the seedlings to breathe fresh air, and then used as a channel for putting the seedlings out of the film. Open your mouth from small to large and gradually strengthen exercise. In case of sudden cooling. Cover it with grass. When the outside air temperature is stable above 20℃ or the seedling leaves are covered with film, the seedlings can be released and covered. However, in case of low temperature, the emergence of seedlings should be delayed, and the anti-baked seedlings should be padded with clods under the film. The temperature in the shed should be kept at 22-25℃ when the small bow shed is covered twice, and it can be released when the outdoor air exceeds 25℃ in sunny morning (it often reaches above 35℃ at noon). Open the shed on the lee side and gradually increase it. After full exercise, the outdoor average daily temperature can reach above 20℃.
(2) Topdressing
1. The amount of topdressing should be determined according to the absorption law of watermelon. The fertilizer absorption capacity of watermelon can be roughly divided into three stages: the seedling stage (before overgrowth) is a slow absorption stage, absorbing 0.5% of the total amount of three elements; The jointing stage is an accelerated absorption stage, accounting for 14.5%-30% of the total, and the fruiting stage is a high-speed absorption stage, accounting for 70%-85% of the total. During the growth of watermelon, nitrogen was absorbed earlier, the jointing stage increased rapidly, and the fruit swelling stage reached its peak. Phosphorus was absorbed more at seedling stage, the peak of absorption appeared earlier, and the fruit expansion period gradually decreased. Potassium was absorbed less at seedling stage, increased slowly from vine extension stage to fruit setting stage, and increased sharply at fruit expansion stage. Therefore, the amount of topdressing should be well controlled: applying seedling fertilizer lightly, applying vine fertilizer skillfully, applying fruit swelling fertilizer again, and applying rejuvenation fertilizer quickly after picking the first crop of melons.
2. The types of topdressing are mainly quick-acting fertilizers, or fermented cake fertilizers and dry fertilizers. Some people think that a large amount of chemical fertilizer will make watermelon poor in quality and not sweet. According to the experiment, otherwise, as long as the three elements are properly matched, they can completely replace organic fertilizer and further improve the yield and quality. Single application of nitrogen fertilizer or excessive application of nitrogen fertilizer will reduce quality.
3. Time and method of topdressing (1) Fertilizers for seedlings vary from seedling to seedling. Generally, topdressing is applied when the true leaves are unfolded. Open cultivation must be adopted; Plastic film mulching is generally not applied, or weak seedlings. 4-5g of urea or 4-5g of diammonium hydrogen phosphate, or 2-3g of both, are used for each plant, and the furrow is ditched 8 8- 10/0cm away from the seedlings, and the furrow is covered after application. (2) Spreading rattan fertilizer should be cultivated in the open field when the bush is growing (4-6 leaves), and topdressing should be carried out when the film is covered, and a small amount of chemical fertilizer should be added when the cake is fully decomposed. Must be combined with nitrogen, phosphorus and potassium. Generally, 25-50 kg cake fertilizer plus 10- 15 kg calcium superphosphate and 5-7 kg urea per mu is called vine-promoting fertilizer. The method is: on one side of the vine, ditch 20 cm away from the seedlings, with the depth and width of 10 cm respectively, apply human fertilizer and bury it with soil. (3) Fruit swelling fertilizer, that is, when the second and third female flowers set fruit, quick-acting chemical fertilizer should be applied when the young fruit eggs are large. Mainly phosphorus and potassium, combined with nitrogen fertilizer, generally using phosphorus and potassium15-20kg per mu, plus urea10kg and potassium sulfate10kg. Or diammonium phosphate 15 kg, potassium sulfate 10 kg, urea 5 kg and calcium magnesium phosphate 5 kg. If coated on the back of melon vines, you can cut the ground, and ditching is not allowed to avoid damaging the roots. Generally, topdressing (especially nitrogen fertilizer) is not needed in the frosting period to avoid fruit and leucorrhea (yellow and white flesh center and pedicel to fruit pedicel). However, when the vine leaves are aged and yellow, potassium dihydrogen phosphate and urea 1: 1 can be mixed to make a 0.3% solution and sprayed with fertilizer.
(3) Watering According to the water demand of different growth stages of watermelon, timely watering is the guarantee of high yield. There is little water demand at seedling stage, so it is generally not watered to avoid lowering the soil temperature. Mainly through saving water and squatting seedlings, the root system is promoted. When cultivated in the open field, water should be given in time (that is, insufficient soil moisture should be supplemented) to prevent dry and hard seedlings from appearing. The method is: combined with applying seedling fertilizer, pour small water in the fertilizer ditch, and bury the soil after the water seeps out (called dark pouring), preferably in sunny morning, so as not to cause the ground temperature to drop. When the trees are clustered, it is necessary to combine the forced stretching of vine fertilizer with dark irrigation to promote vines, and slowly irrigate the soil with small water, depending on the sky, the ground and the seedlings. The fruit must be watered during the expansion period, which is the key moisture to ensure high yield. After taking out the swollen fruit, water it slowly until it is soaked. Water every 5-7 days, and use the border to keep the ground moist. If the cultivation is covered, it can be poured in the ditch between two vines, so as not to be soaked.
(4) pruning and squeezing vines
1. Full-branch watermelon has strong axillary bud germination ability, which is easy to form multiple branches and consumes a lot of nutrients. Insufficient fertility will inevitably lead to small melons and poor quality. Therefore, it is necessary to straighten properly to form a reasonable vegetative body, which is conducive to ventilation and light transmission, improve photosynthetic efficiency and promote fruit setting and fruit growth. (l) Pruning method: It varies with varieties, fertility and density. Generally applicable methods are: single vine, double vine and three vine pruning. Single vine means that only the main vine is left, which is suitable for high-density breeding and cultivation in greenhouses. Double vine straightening is to choose a strong lateral vine at the base of the main vine to climb parallel or with its back to the main vine. Suitable for medium-density early-maturing varieties. Three vines pruning is to select two strong lateral vines at the base to go hand in hand with the main vine, commonly known as one horse and three arrows. It is suitable for large melon varieties with low density, high fertilizer and water content and developed nutrition. Now some only manage fertilizer and water, do not prune, indulge in growth and save manpower. This variety with weak branching ability can also achieve a good harvest, but it is not suitable for use because of its large amount of fertile soil, small melon, poor quality and low output value. In particular, varieties with strong branching schools will reduce production by more than 30% without pruning.
(2) The whole school time: it is advisable to cultivate in the open field as soon as possible, and you can start pruning as soon as the faucet is turned. Covering cultivation should be carried out later. When the length of the main vine is 40-50 cm and the length of the lateral branches at the base is 15 cm, it is not conducive to root growth too early. Too late will consume more nutrition. After sitting on the melon, it is generally not trimmed except for 2-3 lateral branches in front and behind the melon.
2. First of all, we should press the vines (also known as cultivating piers or stabilizing seedlings). After the trees are overgrown, they are top-heavy when cultivated in the open field and are easily blown off by the wind. The base of the seedling must be stable. First, the dry soil at the base is gently pulled open, and the seedlings are crushed with wet soil along the direction of vine extension, thus cultivating a small mound. Generally, there is no pier in the small bow shed. When the main vine is 60-80 cm long, wire rods are used to prevent the membrane at the tip of the vine from being burnt. The functions of pressing vines are as follows: First, the vines are fixed to prevent the seedlings from being blown by the wind, which will cause damage to vines and young fruits. Second, the main lateral vines are evenly distributed between rows to improve photosynthetic efficiency. Thirdly, the relationship between vegetative growth and reproductive growth can be adjusted, so that the leaves of lianas can accumulate more nutrients and become stout, which is beneficial to fruit setting and fruit growth. Fourthly, pressing vines can promote adventitious roots in vine nodes and expand the absorption area. The methods of pressing vines are divided into open pressing and dark pressing. Open pressure is to use clods to press between tendrils. First scrape the lower surface of the vine flat, then take the compacted wet block with a melon shovel and tighten the vine. Dark pressure is to bury a section of melon and vine in a crowd. First, level the ground with a melon shovel, insert it into the soil to a depth of 6-8 cm, swing the melon shovel and squeeze it into a groove, or make it into a small groove with a width of 3-4 cm and a length of 8- 10 cm. Put the vines in the trough and gently squeeze them with soil to bury them, so that the vines and petioles will not be injured and the leaves will not stick to the ground. Open pressure is suitable for areas with thick and humid soil and high groundwater level. Areas with dry sand and little rain and low groundwater level are suitable for dark pressure. Press vines in the afternoon. In the morning, vines are brittle and easy to break. The light weight of rattan can adjust the growth of rattan leaves. If the vine grows vigorously, it will be pressed close to the top of the vine with heavy pressure, leaving only a small part of the top, which can control the growth of the top of the vine, promote the sturdiness of the middle and lower leaves and facilitate fruit setting. Weak growth should be lightly pressed to accelerate the growth of rattan leaves. Using back pressure on the vine is to press the vine back, and then come back, even the main vine touches the top, pick the heart and change the main side. Generally, pressing rattan three times is called three knives, and the interval between each knife is about 50 cm. The first knife is important, the second knife is hard, and the third knife is to press the melon firmly. As long as you sit on the melon, you won't press it again. (5) Fruit setting management
1. The ideal fruit setting position is the second and third female flowers on the main vine. Most of the first female flowers are stunted and form small fruits, which are deformed, thick-skinned and easy to be hollow. The reason is that the temperature is low when flowering and fruit setting, the vegetative body is small, the leaves are less nutritious, and the fruit grows slowly, so it should be picked as soon as possible. Carry out artificial pollination to ensure that the second and third female flowers set fruit. Pollination time: 7- 10 on sunny days and 8-10 on cloudy days, but the fruit setting rate is the highest within 2 hours after flowering, and the stigma secretes mucus after10, which affects pollination and fruiting. Rainfall is the biggest obstacle to pollination and fertilization, and the female flowers that cannot be pollinated and fertilized will inevitably fall off. If it rains 3 hours after pollination, pollen tubes have entered between columns, which generally has little effect on fruit setting. Pay attention to the weather forecast, prepare a small paper bucket to cover the pollinated female flowers against rain, and take them out two days later.
2. Generally, the number of melons is one plant, which is a strong tree. From the end of frost on the main vine to a fixed time, choose a melon on the side vine. Integrated technology of three rattan. The main vine does not sit on the melon, leaving one vine on each side, which is called Erlong Zhu Tie. At the same time, top the main vine and knock it down on different poles. For sister melons (divided into two sections), twin melons (two in one section) are weak and strong. Thereby reducing nutrient consumption.
3. Protect the melon and make a melon table. Tilt the table with wet soil, and put the young melon on the table to prevent the rain from soaking. Pay attention to prevent the sun, turn the melon gradually along the veins, prevent the rain from rotting, and make the skin color uniform.
VII. Maturity and Harvest
(I) Identification of Watermelon Maturity The sign of watermelon maturity is the seed. The pulp of watermelon presents the unique color of this variety, and the seed coat becomes hard. Fruit maturity is the main aspect to measure the quality of watermelon products. The melon with poor maturity has thick skin, light color and low sweetness. Overripe melon has disintegrated pulp cells, soft tissue, inverted pulp, chaff core and hollow. Identification methods include calculation, watching, listening and trying: it takes 28-30 days for early-maturing varieties to blossom and mature; It takes 3 1-35 days for middle and late maturing varieties; Late-maturing varieties need 36-40 days. Marking in batches during flowering or artificial pollination, so as to harvest in stages. The same variety, in the fruit growth period, has high temperature, sufficient sunlight, early maturity and low temperature on rainy days. But the accumulated temperature of physiological maturity is equal. Early maturity is 700-800℃, middle maturity is about 900℃, and late maturity is about 1000℃. Look: Cooked melons indicate that the skin is aging and shiny (oily skin), and the cream disappears in large quantities. The shadow turns yellow. Most of the patterns outside the skin grow from the fruit stalk to the pedicel, which is called the pattern heel. The top of the melon is sunken and the bristles on the handle are sparse. Listen: Listen to the sound with your hands. Ripe melons are popping. For example, popping is raw melons, low tooting is overripe, and coarse melons are hollow or rotten melons. And the variety with thick skin and much meat, although low in voice, is unfamiliar. Although the crisp and thin-skinned variety has a clear voice, the melon is ripe and the test is fluctuating. Try: Hold the melon in your left hand and pat it gently with your right hand. If the left hand feels obvious fluctuation, it is a ripe melon. If there is little or no fluctuation, it is not very ripe or raw. The reason is that the cavity of pulp cells of mature melons and fruits is enlarged, the inner glue layer is dissociated, the gap is enlarged and filled with gas, so the vibration wave is transmitted quickly.
(2) Appropriate harvest maturity should be considered from the aspects of variety, place of sale and shelf life. For varieties with thin and easy-to-crack skin, such as Xin Jing 1, 9-minute ripe melons should be harvested for local supply and 8-minute ripe melons for long-distance supply. For varieties with strict maturity requirements, such as Xinhongbao series and Guanlong series, nine-minute ripe melons should be used for long-distance transportation and marketing, and 10 ripe melons should be used for local supply. 8-9 minutes ripe melons need to be harvested for a week. Matters needing attention during harvesting: 1. Cutting the melon handle with a knife is beneficial to distinguish freshness from freshness. Second, harvest in the early hours of sunny days, do not harvest in rainy days, and harvest slowly after rain. Don't get exposed to the sun or rain after harvest. Third, handle with care when harvesting. Fourth, you can't hurt consumers by being raw and cooked. Selling more money just for an early listing is often counterproductive.
Eight, the second achievement technology
(1) The principle of long root life of secondary fruit watermelon. After harvesting, the early-maturing cultivated head melon is in a period when light, heat and rain are suitable for watermelon growth, which can restore the vegetative growth of the aboveground part. By strengthening the management of fertilizer and water, the old vines and the hidden buds on the base will germinate, blossom and bear fruit again, and the second crop of melons can be harvested in 40-45 days. According to the practice in Shandong and Henan, the yield per mu of the second crop of melons can reach 1000-2000 kg, which is 25%-40% of that of the first crop of melons.
(B) the way of secondary results
1. The growth of vine leaves almost stops when the new shoots leave fruit and the head melon expands. After the head melon is fixed, the top ends of the main vine and the auxiliary vine resume to grow and send out new buds. 7- 10 day after the first melon harvest. Because of the high node position, it is not conducive to nutrient transportation, small fruit shape and low yield. But the method is simple.
2. Auxiliary vines set fruit, cut off the main vines of melons from the base, cut with the harvest, clear out the fields for ventilation and light transmission, and reduce germs. Then, the yield of melon using auxiliary vines is higher. But the second crop of melons was not neat.
3. Regeneration by pruning vines After harvesting the first crop of melons, cut off the rotten old seedlings at a distance of 30cm from the roots, and use the buds hidden at the base to germinate. The new technology can grow in 3-5 days after cutting vines, and can set fruit in 10- 15 days. The fruit expands rapidly, and the melon is large and tidy, about 500 kilograms higher than the main and auxiliary vines.
(C) the key technology of secondary fruit setting
1. should be implemented on the basis of early-maturing varieties, early-maturing cultivation and adequate nutrition, and only one melon should be left per plant.
2 timely prevention and control of pests and diseases, especially powdery mildew, epidemic disease, virus disease and aphids. Remove weeds, rotten fruits and diseased plant residues in the field.
3. Rational fertilization and watering. Immediately after harvest, each plant should be applied with 15-20g urea combined with watering to promote the formation of new vines. When sitting melons, young melons and walnuts are 70%-80% big, apply 25-30 kg of phosphorus, potassium and ammonium nitrate (compound fertilizer).