1. Preliminary preparation

1. Selection and preparation of melon fields: Sandy loam soil with higher terrain, convenient irrigation and drainage, sufficient light and fertile soil is suitable for melon fields, and no other melons have been planted in 3-5 years. The melon fields are deep-frozen in autumn and winter, and the drainage ditches are opened. About a week before planting, the land is prepared and ridges are applied, and 50kg of compound fertilizer, 10kg of urea, 20kg of potassium fertilizer, 100kg of cake fertilizer, and 1000-2000kg of farmyard manure are applied per mu as base fertilizer. Dig drainage ditches around, and in rainy areas, cover with plastic film while the moisture is good.

2. Preparation and disinfection of nutrient soil The nutrient soil should be fertile, complete in nutrients, good in permeability, free from insects, sterile and without grass seeds. The nutritious soil can be prepared by mixing 70% garden soil (unplanted melons) plus 30% decomposed compost, and adding 0.5kg compound fertilizer per 100 kilograms of nutritious soil. disinfect.

The timely sowing

1. Sowing timing and method Sowing between the Jianghuai and Huaihe Rivers is in the middle and late March, and in the south of the Yangtze River, it is appropriate to sow from the end of February to the first ten days of March. To ensure the temperature, double sheds are generally used to cover and heat the seedlings. The timing of seed soaking is carried out when the tail is cold and the head is warm. One week before soaking, the seeds should be fully sun-dried to improve the permeability of the seed coat, improve the vigor of the seeds, and effectively kill the pathogenic bacteria attached to the surface of the seeds and reduce the seedling stage diseases. The occurrence of seedlings can effectively improve the germination rate and seedling rate of seeds. The seeds can be soaked in warm water at 55°C under natural cooling for about 2.0 hours. After thorough washing (washing with detergent or sand), the seed hilum is opened with teeth or pliers, and then germination is initiated. When priming, first place the seeds at a temperature of 32-35°C for 4-5 hours to promote rapid germination, and then continue priming at a temperature of 28-30°C, and start sowing when the seed buds are 1.0cm. The method of sowing is as follows: one day before sowing, the nutrient bowl is fully poured through the bottom water and covered with plastic film for use. When sowing, first make a small hole about 1cm deep in the center of the nutrient bowl, put the tip of the bud downward, stick the soil on one side of the bud, lay the seeds flat on the soil surface, and then cover with soil, with a thickness of about 1-1.5cm. Transplanting is carried out when the two leaves are in one heart, and the plant spacing is set as: 0.6-0.8m. When planting seedless watermelon, one-tenth of the ratio should be planted with ordinary seeded watermelon as the pollen source, supplemented by artificial pollination.

2. Seedbed management

 (1) Temperature management From after sowing to before emergence, the seedbed must maintain a high temperature to facilitate rapid germination. At this time, the temperature should preferably be kept at 30 °C ± 5 °C; after unearthed, the temperature can be maintained at 20-25℃ to prevent leggy growth caused by high temperature and high humidity; after one leaf and one heart, it should be gradually ventilated and cooled from small to large until it is consistent with the external environment, so as to cultivate strong seedlings and make them adaptable to the outside world after transplanting condition.

(2) Humidity management During the whole seedbed period, water supplementation is not recommended in principle. If the normal growth of seedlings is affected by insufficient water, the seedbed water supplementation can be considered.

(3) Other management measures: ① Manual shelling (cap removal): When seedless watermelons emerge, they are generally unearthed with their shells unearthed. If the shells are not shelled in time, the normal growth of the seedlings will be affected. Dehulling should be carried out the morning after the seedlings are unearthed. ② Surrounding soil: After the seedlings are unearthed, in order to reduce the humidity of the seedbed, prevent the occurrence of diseases in the seedling stage and prevent the seedlings from falling down, 100 times of dry medicinal soil (thiophanate-methyl) can be used to surround the roots.

3. Colonization and early field management When the external temperature is stable above 15 ℃, the seedlings can be transplanted during the period of two leaves and one heart. Transplanting should be done in the morning on a sunny day. The method is: first make a hole in the planting site, put the seedlings in the hole, put fine soil around it, and pour enough water to fix the roots. After planting, cover with mulch. Seedless watermelon grows slowly in the seedling stage and has poor disease resistance. Therefore, special attention should be paid to the prevention and control of pests and diseases during the seedling stage. The more serious pests and diseases in the seedling stage include: blight, anthracnose, aphids, cutworms, etc.

4. Field Management

1. Fertilizer and water management The fertilizer and water management of seedless watermelon is based on the principle of promoting before, controlling in the middle, and promoting afterward. After the colonization survives, the supply of fertilizer and water should be strengthened. At this time, the top dressing should be based on quick-acting fertilizer, and 3-4kg of urea per mu should be applied to promote its early development; when the vine is about 30cm long, strengthen the control of fertilizer and water to control its prosperity. Long, promote its early fruit. 7-10 days after fruit setting, topdressing should be done in time, 5-10kg of urea, 15-20kg of compound fertilizer, and 10kg of potassium fertilizer per mu to promote the rapid expansion of the fruit. Fertilization can be applied in stages and in batches, supplemented by irrigation. In the early stage of fruit expansion, water should be irrigated every 3-4 days. In the peak period of fruit expansion, the number of irrigation should be considered according to weather conditions. Irrigation is based on the principle of a small amount of time to reduce the occurrence of hollow deformed fruit, and do not become dry and wet.

2. Pruning and pressing vines When the main vine grows to about 70cm, it should be pruned and pressed in time. Generally, 3-4 vines are used for pruning. Strictly prune before fruit setting, remove excess lateral vines and sun vines, and let them grow after fruit setting. During the growth period, if there is a lot of rain, it can be considered to cover a layer of wheat straw or rapeseed straw in the field to fix the stems and vines, reduce the field humidity, and reduce the occurrence of rotten vines and diseases.

3. Artificial assisted pollination Seedless need to use artificial assisted pollination, and pollination is carried out in the morning when the female flowers are fully opened. When pollinating, the action should be gentle, and the amount of pollination should be sufficient and even, so as to improve the fruit setting rate and reduce the proportion of deformed fruit. In rainy days, caps should be taken for pollination.

4. Fruit thinning, fruit padding and fruit turning. Seedless watermelons have good fruit setting habits. One plant can bear many fruits, but the fruit with 15-30 female flowers is the best, and the one that is too close or too far from the main root is on top. The fruits are generally small, hollow and deformed, and most of the low-node fruits will have more colored and deflated seeds. The fruits are not commercially available and are generally not reserved. Fruit thinning can be carried out 5-10 days after fruit setting, 2-3 fruits are retained per plant, and a pad is placed under the retained fruits to prevent mechanical damage and rotten fruit. 25 days after fruit setting, the fruit should be turned over in time to promote the fruit to be evenly ripe and the color to be consistent.

5. Prevention and control of diseases and insect pests The principle of prevention and control of diseases and pests should be the principle of combination of prevention and control. The diseases and insect pests that damage watermelon mainly include the following: seedling disease, anthracnose, blight and fusarium wilt. Diseases at the seedling stage should be prevented and treated by soil disinfection, seed disinfection, reducing soil moisture and surrounding roots with medicinal soil. Anthrax and blight mainly occur under suitable temperature and high humidity conditions, and special attention should be paid to prevention with Bordeaux mixture at this time. Immediately after the onset of the disease, it should be treated with 800-fold liquid of Keto or green milk copper. Fusarium wilt should be prevented by avoiding repeated cropping or by grafting. After the onset of the disease, the supply of fertilizer and water should be controlled, the diseased plants should be removed immediately, and the roots should be irrigated with 600 times liquid of thiophanate, Kangkuling, and Rhizoma. Insect pest control: Underground pests are mainly soil disinfection, manual hunting and trapping; aboveground pests are generally controlled by chemical agents, and BT and chlorfenurin can be used for chemical control. Pesticide control of diseases and insect pests should pay attention to the frequent use of alternate.

5. Harvest in time Seedless watermelon can mature in about 35 days after setting fruit. At this time, the mature fruits can be harvested in batches, and a small piece of stem can be appropriately taken when harvesting. Freshly picked melons do not need to be listed immediately, but should be stored in a ventilated, dry and cool place for 3-5 days before being listed, which can not only make the color of the melon flesh better, but also make the melon skin thinner and have a better flavor. .

 (Note: This article is reproduced for reference only)