Open-field Melon Cultivation Techniques and Management Key Points
1. Production site conditions: 1.1 Temperature conditions The minimum temperature required for thick-skinned melons is 15°C, the optimum temperature is 18°C-32°C, and the effective accumulated temperature ≥15°C required throughout the growth period is above 1500°C. 1.2 Soil conditions The soil layer is deep, with a pH of 7.0-8.0 being suitable, soil salt content below 0.3%, and a loam or sandy loam texture...
1. Production site conditions:
1.1 Temperature conditions
The minimum temperature required for thick-skinned melons is 15°C, the optimum temperature is 18°C-32°C, and the effective accumulated temperature ≥15°C required throughout the growth period is above 1500°C.
1.2 Soil conditions
The soil layer is deep, with a pH of 7.0-8.0 being suitable, soil salt content below 0.3%, and a loam or sandy loam texture. Organic matter content above 1%, with a crop rotation of more than 5 years.
1.3 Irrigation conditions
The terrain is flat, and Yellow River water (or machine wells) can be used for irrigation, with irrigation and drainage facilities matched.
1.4 Production site environment
Select sites with good ecological conditions and far from pollution sources; the test results for air, water quality and soil should meet the requirements of ny/t391-2000 (Green Food Production Site Environmental Quality Standard).
2 Seeds and their treatment
2.1 Variety selection
2.1.1 Melon variety selection:
According to market demand, select varieties that adapt to local environmental conditions with high yield, good quality, disease resistance and storage-transport tolerance, such as Zao Huanghou, Ganmibao, Keqi Mibao, Youmibao, Yujinxiang, Xicheng No. 3, etc.
2.2 Seed quality
Purity above 95%, cleanliness above 98%, germination rate above 90%, and moisture content below 7%.
2.3 Seed treatment
2.3.1 First soak seeds in warm water, using 55°C warm water (two parts boiling water mixed with one part cold water) while stirring continuously for 15 minutes, then add cold water to bring to room temperature. Then soak the seeds in 0.2% potassium permanganate solution or 500 times diluted carbendazim solution for half an hour, then soak in clean water for 4-6 hours.
3. Land preparation and fertilization
3.1 Base fertilizer: Combined with autumn plowing, apply 3000-5000 kg of decomposed organic fertilizer per mu, and irrigate after plowing to preserve soil moisture.
3.2 Land preparation
Before sowing, harrow, rake and roll in a timely manner to achieve a level, loose plot free of root stubble and with good soil moisture.
3.3 Seed fertilizer
Before sowing, apply 20 kg/mu of diammonium phosphate, 5 kg/mu of urea, and 10 kg of potassium sulfate compound fertilizer in a concentrated deep application, mixed and applied deeply at one time. Or apply 50 kg/mu of melon-specific fertilizer in a concentrated deep application.
3.4 Fertilization method and soil disinfection
Draw lines at a row spacing of 3 m, use a three-leg seed drill, with the middle leg 40 cm from both sides of the line, and sow the seed fertilizer and poisoned soil. Place the seed fertilizer in the two side legs and the poisoned soil in the middle leg. To prepare the poisoned soil, mix 0.2-0.3 kg of 50% carbendazim or dexon with 15 kg of sieved fine soil per mu evenly.
4 Sowing
4.1 Digging furrows and making beds
Adopt the cultivation method of digging furrows, high beds and film mulching, using the line as the center and opening furrows with a plow or by hand. The furrow opening width is 50 cm, bottom width 30 cm, depth 25-30 cm, ensuring the furrow bottom is flat and straight and the furrow ridges and slopes are neat and uniform.
4.2 Film mulching method
After digging the furrow, cover one film on each side of the furrow edge with 70 cm plastic film, or use 140 cm plastic film to cover the furrow together; dig the furrow and cover the film at the same time, pull the film tight and press it firmly to prevent moisture loss.
4.3 Sowing time
4.3.1 Melon sowing time
For open-field film-mulched sowing, it should be done when the soil temperature at a depth of 10 cm stably passes 15°C, and the seedling emergence period should be set at the end of late frost. For early-maturing cultivation, the sowing period should be April 15-20; for mid-to-late-maturing cultivation, the sowing period can last from early May to early June.
4.4 Planting density
4.4.1 For small-fruit varieties, use a center-to-center row spacing of 300 cm, with a small row of 70-80 cm, a large row of 220-230 cm, and a plant spacing of 50 cm, leaving 890 plants per mu.
4.4.2 For large-fruit mid-to-late-maturing varieties, the row spacing is 300 cm, plant spacing 55 cm, leaving 800 plants per mu.
4.5 Sowing method
Seeds should be sown 10-15 cm from the furrow ridge, between the two fertilizer bands. For early-maturing cultivation, make a 10 cm sowing hole under the film and sow the seeds at the bottom of the hole, then cover with 1.5 cm of fine soil. For mid-to-late-maturing sowing, the sowing depth should not exceed 3 cm; open holes for dibbling and leave seedlings in a triangle, sowing 2 seeds per hole.
5 Field management
5.1 Checking seedlings and final thinning
After the seedlings emerge, check the seedlings promptly, replant after sprouting, cultivate and weed in a timely manner, and thin to the final stand when there are 2-3 true leaves.
5.2 Pruning and fruit setting
5.2.1 Single-vine pruning (one-dragon pruning)
Remove the secondary vines that emerge from nodes 1-7 of the main vine, retain fruit on the secondary vines that emerge from nodes 8-10, and pinch the fruiting secondary vine 2 leaves after the fruit. When the fruit grows to a diameter of 6-8 cm, set the fruit, selecting and retaining only one fruit per plant. Remove the secondary vines that emerge from nodes 11-18 on the main vine; after node 18, no more pruning is done, and pinch the main vine at 25 leaves.
5.2.2 Improved single-vine pruning
Secondary vines emerging from nodes 1-4 of the main vine are pinched at 2 leaves, secondary vines from nodes 5-7 are removed, and fruit is retained on secondary vines emerging from nodes 8-10; when the fruit grows to 6-8 cm, set the fruit. Select and retain only one fruit per plant. Remove secondary vines emerging from nodes 11-18 and pinch at 25 leaves. Compared with single-vine pruning, improved single-vine pruning not only increases leaf area but also benefits normal root growth, creating conditions for high yield and good quality.
5.3 Watering and fertilization
Generally no watering during the seedling stage; give the first light watering during the vine extension stage; during the fruit expansion stage (fruit diameter 6-8 cm), give the second watering, and at the same time topdress 15 kg of potassium sulfate compound fertilizer and 15 kg of urea per mu; the watering should not exceed 2/3 of the furrow depth, and water must never overflow onto the bed surface.
5.4 Foliar fertilization
After the first pruning (at 6-7 leaves), spray 0.2-0.3% urea once together with pest and disease control; after fruit setting, spray 2-3 more times with 0.2-0.3% monopotassium phosphate and other foliar fertilizers together with disease control, with an interval of 7 to 10 days between each spraying; foliar spraying is prohibited during the flowering period.
5.5 Fruit management
Carry out fruit selection, fruit setting, fruit cushioning and fruit turning in a timely manner. Fruit setting is done when the young fruit is the size of an egg; fruit cushioning and fruit turning are carried out in the late fruit expansion stage of the melon.
5.6 Pest and disease prevention
Before disease onset, spray 27% high-fat film emulsion at 80-100 times dilution to form a protective film on the leaf surface, which can reduce disease occurrence.
5.7 Pest and disease control
At present, the main diseases harming melons are: bacterial diseases, fungal diseases and viral diseases. Bacterial diseases include bacterial leaf spot (fruit spot disease) and bacterial angular leaf spot; fungal diseases include gummy stem blight, downy mildew, powdery mildew, leaf blight (black spot disease), and fusarium wilt; the main insect pests are leafminers and aphids.
5.7.1 Control of bacterial leaf spot and bacterial angular leaf spot:
Spray with agricultural streptomycin, 7 g per bag added to 45 kg of water, or new phytomycin 0.2 ml/L, or 50% copper hydroxide wettable microgranule powder at 400 times dilution, or 60% baijuntong wettable powder at 500 times dilution.
5.7.2 Control of gummy stem blight:
Spray with 75% chlorothalonil wettable powder at 600 times dilution, or 70% thiophanate-methyl wettable powder at 800-1000 times dilution, or 80% mancozeb wettable powder at 800 times dilution. For stem disease, use 1:50 thiophanate-methyl or add a small amount of oxadixyl or streptomycin liquid to make a paste and apply it to the diseased part.
5.7.3 Control of downy mildew:
Spray with 47% kasugamycin-copper hydroxide wettable powder at 600 times dilution, or 72% cymoxanil wettable powder at 600 times dilution, or 72.2% propamocarb aqueous solution at 600-800 times dilution, or 64% oxadixyl at 600 times dilution, or 25% metalaxyl wettable powder at 500 times dilution.
5.7.4 Control of powdery mildew:
Spray with 2% agricultural antibiotic 120 aqueous solution at 200 times dilution, or 47% kasugamycin-copper hydroxide wettable powder at 600 times dilution, or 40% flusilazole emulsifiable concentrate at 800 times dilution, or 10% myclobutanil at 2500 times dilution, or 20% triadimefon emulsifiable concentrate at 1000 times dilution. Use the above pesticides alternately, applying once every 7-10 days for 2-3 consecutive applications.
5.7.5 Control of melon leaf blight (black spot disease):
Spray with 75% chlorothalonil wettable powder at 500 times dilution, or 50% iprodione wettable powder at 1000-1500 times dilution, or agricultural antibiotic 120 aqueous solution at 200 times dilution, or 50% procymidone wettable powder at 1000-2000 times dilution.
5.7.6 Control of fusarium wilt:
Use 58% metalaxyl-mancozeb wettable powder at 500 times dilution, or 64% oxadixyl at 400 times dilution, or 95% lüheng No. 1 at 3000 times dilution for root drenching and spraying.
5.7.7 Control of melon viral disease:
Spray with 20% virus A wettable powder at 500-700 times dilution, or antiviral agent No. 1 at 300 times dilution, or 1.5% zhibingling at 800-1000 times dilution.
5.7.8 Control of leafminers:
Spray with 40% lücaibao wettable powder at 1000-1500 times dilution, or 1.8% abamectin at 6000-8000 times dilution, or 20% fenvalerate at 1500 times dilution.
5.7.9 Control of aphids:
Spray with 10% imidacloprid wettable powder at 2500-3000 times dilution, or 50% pirimicarb wettable powder at 2000 times dilution, or 2.5% deltamethrin, 2.5% kung fu, 21% mieshabi emulsifiable concentrate at 4000 times dilution.
During one growth period of melons, each pesticide is allowed to be used only once, and no chemically synthesized pesticide may be used within 10 days before harvest.
6. Management before maturity
In the late fruit expansion stage of melons, turn and cushion the fruit in a timely manner, turning once every 5-7 days, preferably in the afternoon, turning in one direction, and the turning angle should not be too large each time.
When the melon begins to show netting, use grass or melon vines to shade the melon, or use old newspaper bags to prevent sunscald.
7. Harvest
Determine the appropriate harvest time according to the market and the distance of transport. If sold locally, harvest when maturity reaches above 90%; for long-distance transport and sale, harvest at 80% maturity. When harvesting, leave a 3-4 cm fruit stalk to prevent wound infection by pathogens. Collect and store separately, and do not store mixed with non-pollution-free food watermelons.