Giant pumpkins are huge in shape and can weigh more than 100 kilograms per fruit. They are beautiful in appearance and come in red, white, and yellow colors. At the same time, it not only demonstrates the development of modern agricultural breeding and cultivation technology but also is the highlight of agricultural science education. It has broad application prospects in leisure and sightseeing agriculture and is of great development and promotion value.

1 Variety Selection

The variety chooses giant pumpkin, which has huge fruit, red or orange skin, leaves up to 70 cm wide, a strong root system, thick stems, vigorous growth, and a growth period of 120-150 days. This variety has the characteristics of fast growth, easy melon seating, thick flesh, high yield, easy management, and storage and transportation resistance. It has great promotion and development value and is suitable for sightseeing parks, exhibitions, etc.

2 Nursery

2.1 Substrate selection and ratio

Usually, a matrix with good air permeability, water permeability and fertilizer retention is used. The mixed matrix prepared by peat, vermiculite and perlite in a certain proportion is commonly used. The proportion of the matrix is quantified by volume ratio. Stone: perlite = 2:2:1, add 1 kg of compound fertilizer per cubic meter of substrate, and spray or spread 100 g of chlorothalonil or mancozeb. In abnormal weather, the amount of perlite can be increased appropriately to ensure the air permeability of the mixed matrix.

2.2 Seed treatment

Giant pumpkins have thick seed coats and slow germination, so they need to be accelerated. Usually, the method of soaking seeds in warm soup is used for treatment. Soak seeds in warm water at 55-60 °C for 10-15 minutes, add warm water and stir several times, keep the water temperature at 55 °C, and then let the water temperature drop to a normal temperature to soak seeds for 5-8 hours. For the sticky matter on the skin, when the seeds are slightly soft, wrap them with gauze to keep them moist, place them in a constant temperature box at 25-30°C to accelerate germination, and sow after more than 70% of the seeds are white.

2.3 Sowing

Due to the large size of giant pumpkin seeds, you can choose a 16 cm × 16 cm nutrient pot for seedling cultivation. Put the germinated seeds into the nutrient pot (the dewy direction is downward), and the depth of the soil is about 1.0 cm, and then cover it with 1.5 cm. 0-1.5 cm thick vermiculite (perlite can be used instead in winter). If the temperature is low during seedling cultivation, it is necessary to cover with plastic film to keep warm and remove the plastic film after 5-7 days of germination. During the growth of melon seedlings, the 21 cm × 21 cm nutrient pot can be replaced according to the actual growth needs. Under normal weather, the seedling period is 25-35 days, and when the seedlings grow to 4-5 true leaves, they can be planted. Generally, the sowing period is arranged from March to May in the south and April to June in the north.

During the emergence period, the key point is to keep warm and moisturize. The temperature in the shed is preferably 25-30 ℃ during the day, 18-20 ℃ at night, and the relative air humidity is 70%-85%. About 10 days after the melon seedlings emerge, the management should be properly ventilated, the light should be increased, and the temperature should be lowered. The temperature should be 22-26 °C during the day and 15-18 °C at night.

After the cotyledons of the seedlings are developed, spray Puliq according to the safe interval of medication and the actual growth status, aiming at preventing damping-off and blight. 2 to 3 days before transplanting the seedlings, pour 1000 times dilution of 70% dexon powder once to prevent the seedlings from being attacked by pathogens after transplanting.

3 Soil Preparation And Fertilization

The giant pumpkin has a larger shape and a higher yield per plant, so it requires a large amount of fertilizer. The fertilization ratio N:P2O5:K2O=2:1:3, the total amount of fertilizer N per plant is 0.50 kg, and P2O5 is 0. .25 kg, K2O is 0.75 kg, and the planting density is 10-20 m2/plant.

15-20 days before planting, dig 1.5 m3 planting pits (length x width x height = 1.0 m x 1.0 m x 1.5 m), and fill each pit with 60 cm of mushroom dregs and 60 cm of peat , 40 kg of organic fertilizer, and 50 kg of decomposed chicken manure. Mix these fertilizers and substrates evenly in proportion and fill them into the planting pit. After pouring enough bottom water, cover the top with 15-20 cm of peat. Can be used for planting.

4 Field Planting

Plant the melon seedlings of the right age with 4 to 6 leaves and strong growth in the center of the pit, add a small amount of compound fertilizer to the backfill matrix, and water thoroughly, and use a small hoe to lightly loosen the surface on the second or third day when the upper matrix is not sticky. Matrix, increases aeration. After planting slow seedlings, topdress with thin nitrogen fertilizer with water to promote rapid growth of plants. After 7-10 days, start topdressing successively with a concentration of about 5‰. Loosen the surface substrate in time after topdressing and watering to avoid poor ventilation and rotten roots occur.

5 Daily Management

5.1 Timely topping

When planting giant pumpkins, it is usually necessary to keep 2 to 3 main vines, and the side vines are basically not removed. Generally, topping measures are taken when they grow to 7 to 10 leaves (the purpose is to increase the functional leaf area). All the male and female flowers should be removed, and the thicker main vines should be selected to keep the melons. The nodes of the melons should be selected after 20 leaves (the length of the vines is about 2.5-3.0m), and 2-3 melons should be reserved for artificial cultivation. After pollination, when the young fruit grows to the size of a tennis ball, select a positive fruit for cultivation.

5.2 Pollination

The optimum temperature for pollination is 25°C, so as not to cause melons to melt due to high temperature. The pollination time is selected before 8:00 am on a sunny day. When pollinating, pick a fresh male flower, remove the outer petals, shake off the pollen from the stamen to the stigma of the female flower, and then choose two or three petals to cover the pollinated flower. on the female flower. To be on the safe side, dip the prepared forchlorfenuron solution with a brush at the same time, smear the entire melon tire evenly, and finally lay a foam board underneath to avoid contact with the ground. The remaining two or three female flowers are treated in the same way (either on the same day or the next day), and the female flowers that will be produced later will all be removed.

5.3 Pumpkin Protection

The position of the sitting melon should be flat, and at the same time, it should be raised with a foam board, and a growing space of about 1 m2 should be reserved. During this period, the melon vines should also be trimmed. When the melon vines grow to 8-10 m, the growth point of the main vines should be pinched off, and the newly grown side vines should also be headed when they retain about 5 leaves. The male and female flowers that appear should also be removed at any time, and at the same time, they should be accompanied by pressing vines (with a distance of 2-3 m) to increase the root area[5], so as to ensure sufficient nutrients for the growth of pumpkins.

5.4 Fertilizer and water management

Big pumpkin grows very fast, from May to August is the vigorous growth period, and a leaf can grow into a leaf in 3 to 4 days, and enters the period of rapid fruit expansion about 5 days after artificial pollination. At this time, strengthen fertilizer and water management, and fertilize the main root every week Once (rotational application of organic fertilizer and compound fertilizer), the amount of fertilizer applied to each plant is 7.5-15.0 kg, and the fertilization position is 30-60 cm away from the root. In the early stage, nitrogen fertilizer is mainly used, and in the later stage, the lateral roots produced by vine pressure are applied with EM mushroom cake fertilizer every week. Once, apply 50-100 mL of fertilizer to each lateral root position, and the fertilization position is 30 cm away from the root. It is better to stagger the fertilization time of the main lateral root.

6 Pest Control

6.1 Physical control

①After the pumpkin sits down, pad foam boards and other materials underneath to prevent the bottom of the pumpkin from being bitten by pests or some rotten diseases. ② Hang yellow boards and blue boards to prevent and control aphids, whiteflies and leaf miners. The hanging height should be 15-30 cm from the height of the leaves, and one board should be hung every 2-3 m. It should not be too high, as it will affect the preventive effect . ③ Remove aging yellow leaves and failed flowers in time to prevent mildew caused by high humidity.

6.2 Chemical control

The main diseases of giant pumpkin are powdery mildew, viral disease, downy mildew and so on.

6.2.1 Powdery mildew

White mildew spots appear on the leaves or tender stems when damaged, and in severe cases, the entire leaves are covered with white powder. The disease can occur at 10-30 °C, and the optimum temperature is 20-25 °C. The disease develops rapidly in high-temperature dry and humid alternately. You can choose 600-fold dilution of 2% Kasugami (kasugamycin) aqueous solution, or 25% Amida (Azoxystrobin) suspension, or 10% Shigao (difenoconazole) water dispersible granules 8 000-fold dilution, or 50% Tribe (Kysstrobin) dry suspension concentrate 3 000-4 000-fold dilution for control, cross use, and spray 3 to 4 times.

6.2.2 Viral diseases

The high temperature in summer is very easy to cause virus damage, which mainly relies on piercing and sucking mouthparts such as aphids to feed and transmit viruses. Prevention should be the main focus and comprehensive control should be carried out. The preventive and control agents usually include morpholinidine hydrochloride, virus A, 32% nucleoside bromomorpholine, etc. Due to its main source of transmission, imidacloprid, abamectin, pyridine, etc. Insecticides such as chrysanthemum for prevention and control of virus carriers. Under normal circumstances, if the virus disease is not serious, it is generally enough to use any of the above-mentioned pesticides for three times, but if the disease is serious and the environmental conditions are not conducive to the growth of melon seedlings, the seriously diseased plants should be pulled out as soon as possible.

6.2.3 Downy mildew

Greenhouses and greenhouses are prone to disease when the temperature is 15-25 °C and the relative humidity is higher than 80%. When the weather is rainy, dewy, foggy or continuously rainy weather, the disease will be early and severe. Prevention and control agents can be selected from Dupont Kelu, propamocarb hydrochloride, anti-virus alum, etc. for prevention and control.

6.2.4 Pest control

The main pests of pumpkin cultivation in the greenhouse are aphids, whitefly, and leafminer. Aphids have strong fecundity and can produce 10 to 30 generations a year. The generation overlap phenomenon is prominent. They cluster on the back of plant leaves, tender stems, growth points and flowers, and suck juice from leaves. In severe cases, the plants stop growing, and even the whole plant wilts and dies. ; whitefly has strong fecundity, can parthenogenetic reproduction, population growth is fast, cluster damage, the damaged leaves turn green, turn yellow, wilt, and even the whole plant dies; the occurrence rule of Liriomyza sativae can occur 8 to 10 generations per year in northern areas , of which 4-5 generations occurred in the protected area, and the generations overlapped seriously in the protected area from April to early June and from October to November. Prevention and control agents can be matrine, pyrethrins, chlorpyrifos, emamectin, cyhalothrin, cyromazine, imidacloprid, acetamiprid or isoprocarb fumigants, etc. for prevention and control.