The weather is warm and cool

Biological characteristics like warm and humid climate, not cold-resistant, afraid of humidity, afraid of direct light. Avoid continuous cropping. Slope land and slightly shady plots should be selected for cultivation. The upper layer is deep, loose, fertile sandy soil with good drainage, which is suitable for heavy soil. ㄞ

Cultivation techniques include rhizome propagation, hole sowing or strip planting. When picking ginger in autumn, choose thicker and yellowish ones. Glossy, disease-free rhizomes are used as ginger, stored in cellars or stacked in layers with fine sand indoors for later use. In June 5438+0-April in the south and May in the north, the seed difference is taken out and germinated, and then the ginger is cut into small pieces, and each piece has 1-2 strong buds. In hole planting, holes are drilled according to the row spacing of 40cm×30cm, and the depth is 13- 17cm. First, fill the pits with manure water. After the soil permeates, plant 1 slice of ginger horizontally in each pit. Finally, cover with fine compost and soil. Ribbon planting shall be ditched according to the row spacing of 40cm, and planted according to the row spacing of 27cm after applying base fertilizer, and the soil shall be covered and the ground shall be flat. Sichuan production areas pay great attention to the depth of sowing, sowing deep (digging a pit about 30cm), and constantly cultivating soil to form a piece of ginger, which is the source of ginger; Medicinal ginger is made by shallow sowing (digging pit 5- 10cm) and is the source of dried ginger.

Field management found that plants were missing after emergence and replanted in time. Weeding in intertillage for 3-4 times and topdressing for 4 times throughout the year, with organic fertilizer and compound fertilizer as the main fertilizers. The growth period is strict with water, and there is no shortage of water. If there is a factory guide, water and moisturize it in time, and stop watering before harvest 10d.

Pest control diseases include rot, commonly known as ginger temperature, which is easy to occur in high temperature and rainy seasons. Soak the seeds in bordeaux solution 10min, pull out the diseased plants when the disease occurs, and disinfect the diseased spots with lime. The pest is Asian corn borer, which destroys the stem of ginger from August to September. The heart leaves were filled with 90% trichlorfon 1000 solution. Ginger makes butterflies, and butterflies harm leaves with larvae. Spray with 80% dichlorvos 1500 times solution.

Structure and performance of small arch shed

The small arch shed should be north-south, with an area of1.4-1.6m.. First of all, a melon ditch with a width of 60 cm and a depth of 40 cm should be opened in the middle. After fertilization, the soil and fertilizer should be deeply turned to make a turtle-shaped cultivation bed with a width of 60 cm and a height of 10- 15cm. Water ditches with a width of 30 cm should be formed on both sides of the bed. Insert 1-10.2m into the ridge, and form an arch frame with a root length of 2m and a width of 4cm/0.5m and a height of 0.7m.. The frame is fastened with a 2-meter-wide film, and the surrounding area is compacted with soil. The shed spacing is about 1 m. 240-260 bamboos per mu. 0.0 14 mm agricultural film is about 7.5 kg or 0.03 mm agricultural film is about 16 kg, and 0.005 mm plastic film is about 2.5 kg. The minimum temperature of the small arch shed with this structure can be stabilized above 5 degrees in the first ten days of April in general years, which can meet the requirements of watermelon slow seedling stage.

Cultivate grafted seedlings

At present, grafted seedlings are usually cultivated in a simple greenhouse with heating facilities. Pumpkin or gourd is used as rootstock, and the method of docking or grafting is adopted. The seedling age is about 40 days.

1. The seedbed is set in the north-south direction, and the width from east to west is1.2m. The ridge platform is required to be flat, with a width of 30-40cm and a height of 15-20cm.

2. Nutritious soil should be loose, fertile, water-retaining and fertilizer-retaining, free from germs and eggs. Generally, 2 parts of fertile pastoral soil and 1 part of sieved organic fertilizer which has been fully decomposed by high-temperature fermentation in summer are selected, and then 0.5 kg of crushed diamine or 1 kg compound fertilizer, 3-4 parts of 50% carbendazim and 1 part of 50% phoxim are added to each cubic meter, and after being fully mixed, they are put into a container with a diameter of 8 cm and a height of1part. 1 A week before sowing, water the pot thoroughly.

3. Before disinfection and sowing in the greenhouse, use sawdust mixed with 2 kg/mu sulfur powder and 0.2 kg/mu dichlorvos to fumigate the greenhouse for 24 hours.

4. Seed treatment (1) Black-seeded pumpkin seeds have strong dormancy, and the germination rate of seeds in that year is only about 40%. Gibberellin is needed to break dormancy. The specific method is: soak the seeds in warm water for 1-2 hours, scrub to remove impurities, and then soak them in gibberellin for 24 hours. If seeds aged for one year are used, they can be directly soaked for 12 hours. (2) The seed coat of gourd is thick and it is difficult to absorb water. Seeds germinate slowly, irregularly, with low germination potential and germination rate. You can burn it with hot water. Use it first.

Watermelon carving photo gallery (20 photos) immerse the seeds in cold water, then pour in hot water with 80-90 degrees and keep stirring in one direction until the water temperature drops to 70-75 degrees and keeps about 1 min. Finally, pour in cold water to reduce the water temperature to 20-30 degrees, and continue to soak the seeds for 24-36 hours, or refer to the pumpkin seed treatment method and use1min. (3) Watermelon seed treatment: one method is to soak the seeds with 50% carbendazim or 500 times topaz for 30 minutes, take them out and wash them, and then soak them in warm water for 6-8 hours; The other is to blanch the seeds with hot water of 80-90 degrees for 3-5 seconds, then add cold water to reduce the water temperature to about 55 degrees, soak for about 10 minute, and then soak at 20-30 degrees for 6-8 hours.

No matter which method is used to treat seeds, the excess water in the seed coat should be dried or dried before germination, and then wrapped with anhydrous film and placed in an environment of 28-30 degrees to avoid the influence of excessive water and lack of oxygen in the seed kernel on seed germination.

5. Sowing: (1) Docking with pumpkin as rootstock. Soaking pumpkin seeds does not accelerate germination, but sowing watermelon seeds in a nutrition pot at the same time after accelerating germination, sowing two rootstocks and scions, covering with soil 1.5cm, and covering with plastic film. The greenhouse temperature is 30-35 degrees during the day and 18-22 degrees at night, and the soil temperature should be above 18 degrees. After emergence, the temperature dropped to about 25 degrees during the day and to 15~ 16 degrees at night. Watermelon seeds can be sown after germination. Watermelon seeds are sown in the sand table. Scald the sand with boiling water before sowing. After cooling, sow watermelon seeds every 1 cm, cover with soil 1 cm, and cover with plastic film to keep moisture and raise temperature. Put the sand table in a warm place in the greenhouse for about 5-6 days to germinate, and the cotyledons of watermelon seedlings will spread out and turn completely green after a day of sun exposure. At this time, the first true leaf of the gourd has been unfolded, which is the best grafting period for high grafting.

Watermelon seedlings 6. Grafting: (1) Docking of pumpkin and watermelon: When the leaves of pumpkin seeds are flat, remove the growing points, and obliquely cut a knife at the angle of 45 degrees below the cotyledons, with the depth of 2/5- 1/2 of the stem diameter and the incision length of about 1 cm. At the same time, the corresponding part of watermelon scion inclines upward at a 45-degree angle, the depth is 1/2-2/3 neck thickness, and the incision length is the same as that of rootstock. The cut of the scion is embedded into the cut of the rootstock stem, so that the interface between the scion and the rootstock is closely attached and fixed with a grafting clip. After about seven days, the joint healed and the root of the scion was cut off. After 10- 15 days, the grafting clip was removed. (2) Grafting with gourd as rootstock: when grafting, the terminal bud and true leaves of gourd are removed, leaving only two cotyledons, and then a bamboo stick with a 6-8 mm inclined surface at the top is inserted between the vein of the cotyledon of gourd and the stem of gourd, and the inclined surface is inserted downward along the direction of 45 degrees. Cut off the stem of watermelon seedling at the position of 8- 10 mm below the cotyledon, with the section length of 8- 10 mm, remove the bamboo stick, and quickly insert the section of watermelon scion into the gourd rootstock, so that the two sections are close together, and the cotyledons of rootstock and scion cross.

7. Post-grafting management: After grafting, cover the small arch shed in time to moisturize, and shade with a sunshade net. Generally, there is no ventilation for the first three days, 25-28 degrees during the day and 20-22 degrees at night, not less than 18 degrees, and the relative humidity of the air in the small arch shed is kept above 95%. After three days, gradually increase the ventilation and shorten the shading time. After the grafted seedlings survive for about 12 days, the temperature can be reduced to 24-26 degrees during the day and to 16- 18 degrees at night. Pay attention to remove the sprouted lateral buds on the rootstock in time. Spraying drugs to prevent diseases. 3-5 days before planting, the seedlings were exercised at low temperature, and the air release rate was increased during the day, which was 22-24 degrees during the day and decreased to 13- 15 degrees at night.

Adaptability of watermelon (20 pieces) seedlings to small arch shed environment after strong seedling.

Preparation before planting

1. Application of base fertilizer: 2-2.5 cubic meters of fermented chicken manure or 6-8 cubic meters of high-quality manure are applied per mu in combination with ploughing (it is best for qualified households to mix chicken manure and manure for high-temperature fermentation in summer, and it is not easy to burn seedlings after high-temperature fermentation), 30-40 kg of diammonium, 30-40 kg of potassium sulfate and 0/0-urea.

2. Make the bed, cover the ground and buckle the shed.

In late March, make the bed in time on sunny days as required, 7- 10 days before planting, sow on the ground, cover with plastic film, arch, bake and heat.

Field planting

1. Planting date: generally in Shishi and surrounding counties and cities, when the ground temperature of 5 cm in the small arch shed is stable above 12 degrees in late March and early April, you can choose windless sunny days for planting, which, from the phenological point of view, coincides with willow germination and poplar shedding.

2. Planting density: plant two rows per border with a row spacing of not less than 0.7m, and plant 650-700 plants per mu. When planting watermelon flowers, directly punch holes in the covered plastic film according to the plant spacing with a hole opener or a melon shovel, and water the seedlings. Finally, seal the membrane hole with soil and cover the small arch shed in time.

Post-planting management

1. temperature management: (1) colonization-the time from colonization to creeping growth of 5-6 leaves of melon seedlings is about 13- 15 days. Generally, outdoor air is not released in the first three days after planting, which promotes the slow growth of seedlings. After delayed emergence, the ventilation rate can be gradually increased every morning 10:00- 2: 00 pm, so as to reduce the temperature and remove moisture, improve the lighting conditions, reduce the growth rate of plants, improve the stress resistance, and achieve leaf thickness, neck thickness and strong roots. (2) Colorful flag trees and fixed melons: this stage has entered the end of April, and the late frost period has passed, so freeze injury is generally not considered. At this stage, the roots and stems and leaves of plants grow rapidly, which easily leads to difficulties in fruit setting. Therefore, it is necessary to amplify the wind power in the morning and noon, cover the film at night, promote the rational distribution of nutrients, and set fruit early.

2. Pruning method: generally, the three-rattan pruning method is adopted. When the main vine grows to 30 cm long and the branch at the base of the stem reaches 5 cm, two healthy lateral vines with uniform growth are selected for each plant, and the redundant lateral vines are removed as soon as possible.

Generally, the second or third female flower of the main vine is selected for fruit setting, and when the main vine can't sit still, the female flower of the side vine can be selected for fruit setting. Generally, the redundant lateral branches before fruit setting are removed as soon as possible, and 3~6 leaves can be left for topping in the next few sections to increase the leaf area and increase the yield.

3. Fertilizer and water management: When the planting water is sufficient and the length of the main vine is about 50 cm, 5 kg of urea and 5 kg of potassium dihydrogen phosphate 10 kg can be combined with watering. When the young fruit grows to the size of an egg, wash 15 kg of urea and 20 kg of potassium dihydrogen phosphate into each mu with clear water. When the fruit bowl is large, urea 10 kg and potassium dihydrogen phosphate 15 kg can be topdressing per mu according to the soil fertility, and foliar fertilizer can also be sprayed on the cut watermelon to prevent premature senescence of stems and leaves.

4. Artificial pollination: the pollination time is 7- 1 1 every morning, the petals of the male flowers that opened that day are removed, and the pollen is gently smeared on the stigma of the female flowers that have already bloomed. Pay attention to be thoughtful and even in the operation to prevent abnormal fruit.

5. Methods and key technologies of watermelon secondary fruiting: There are two methods. One is vine pruning and regeneration, that is, after the first crop of melons is settled, pay attention to leaving three newly grown vines at the base. After picking the first crop, cut off the old vines 30 cm away from the roots and bear fruit with the new vines at the base. The other is to leave the melon in the new shoots, that is, in the late stage of fruit growth, use the new vines at the top of the main vines and side vines to set the fruit. Generally, it can bloom and set fruit in 7- 10 days. This method is simple in management, but it has high fruit setting, small fruit shape and low yield. The key technology is to prevent disease in the later stage of the first crop of melons, spray fertilizer on the leaves to prevent premature senescence of stems and leaves, clean up the site in time after picking melons, water the roots with rooting agent, and water them with topdressing to promote the healthy growth of new vines.

Cultivation techniques of small gift watermelon

1. Small watermelon has strong adaptability in the cultivation season, and can grow normally when the temperature is above 14℃. Using different cultivation techniques, sowing in summer 1 mid-month to late July, and harvesting in May-10/October.

Protected cultivation in early spring: Seeding and seedling raising in the middle and late February, seedling age 35-40 days, heating and seedling raising, greenhouse planting in the middle and early April, and listing in the early June.

Spring bare land cultivation: sow in late March to late May, and the seedling age is about 30 days. The seedlings in the protected area should be planted in bare land or covered with a small arch shed after the final frost period.

Delayed cultivation in summer protected land: sowing in late July, seedling age is about 20 days. Covered with shed film in early September, covered with thermal insulation straw curtain in early September, and listed around 10.

Second, sowing and seedling raising

Preparation of nutrient soil: There are many methods to prepare nutrient soil. Usually, 2/3 peat soil is mixed with 1/3 seedless melons and screened field soil, or 1/3 decomposed farmyard manure and 2/3 field soil. Add 2 kg of calcium superphosphate to each soil, disinfect with 800 times carbendazim solution, or fumigate with formaldehyde.

Soaking seeds to accelerate germination: soak seeds in warm water at 55℃ for disinfection, and keep stirring until the water temperature drops to about 30℃. After soaking for 4 hours, wash the seeds, then wrap them in a wet towel and put them in an environment of about 30℃ to accelerate germination.

Sowing: The day before sowing, the seedling soil should be thoroughly watered with 800 times of thiophanate methyl solution. When the seed buds grow to about 0.5 cm, plant the seeds in the seedling tray with the buds facing upwards, cover with fine nutrient soil with the thickness of 65438 0.5 cm, and pour 800 times of methyl thiophanate solution through the seedling tray, and keep the temperature at 25-30℃ to ensure the orderly emergence of seedlings. Keep the temperature at 18-28℃ after emergence. The seedbed would rather be dry than wet. In early spring, it is necessary to prevent freezing injury and ensure sufficient light. In summer, seedlings should be prevented from growing in vain at high temperature.

Third, on-site management

Planting: Generally, multi-vine, multi-fruit and whole vine cultivation, the row spacing is 60-80 cm× 180-200 cm, and 530-730 plants can be planted per mu. It can also be cultivated in vertical grid with row spacing of 50 cm× 100— 140 cm, and planted in two rows.

Fertilizer and water: base fertilizer is the main fertilizer, supplemented by topdressing. 53-66 kg of compound fertilizer and 2670 kg of compost should be applied to each mu of base fertilizer, and strip application or spread application should be adopted. After that, the whole growth period is mainly based on "two waters and two fertilizers", that is, spreading vine fertilizer, and after planting for one week, nitrogen fertilizer is mainly applied for irrigation; Expanding melon fertilizer, after one week of fruit setting, mainly applying phosphorus and potassium, irrigation.

The whole vine leaves fruit: the cause and effect are small. In order to obtain high yield, multi-vine and multi-fruit cultivation should be adopted. Generally, 1 main vine and 3-4 secondary vines are kept, or the whole vine is not kept. When keeping fruit, remove the first female flower on the main vine, and the rest can keep the second crop of melon. It is suggested to remove the tendrils below the fruit-setting node as soon as possible.

Pest control: Compared with large watermelon varieties, small watermelon varieties are more resistant to diseases, such as Fusarium wilt, Fusarium wilt, virus disease and anthracnose. It is best to control pests every 7- 10 days.

High-yield cultivation techniques

Watermelon in greenhouse can be harvested 5-6 times at the end of May-June 10, with an average yield of 7500 kg per mu.

Variety selection

Choose Zaojia and other watermelon varieties with early maturity, disease resistance, low temperature and weak light tolerance and strong regeneration ability.

Cultivate strong seedlings

In Nanjing, seeds are usually planted in the middle of June in 5438+ 10, and seedlings are raised in hotbeds with electricity. Make a seedbed with a width of 1 m and a depth of 25 cm in the greenhouse, and the length depends on the number of seedlings. Spread plastic film in the border, sprinkle with fine soil, straw, etc., spread electric heating wire on it, and discharge it into the nutrition bowl. Soak the seeds to accelerate germination until 80% of the seeds are white, and sow each bowl 1 grain. After sowing, cover 0.5 ~ 1 cm thick fine soil and plastic film to build a small arch shed. Cover the small arch shed with a straw curtain at night. Before emergence, the bed temperature was kept at 30 ~ 32℃ during the day and 20 ~ 25℃ at night. 70% of the seedlings are exposed after they are unearthed. After the seedlings are fully sown, the small arch shed should be properly opened to cool down, and the shed temperature should be controlled at 20 ~ 30℃ during the day and at 15 ~ 18℃ at night. Before transplanting, the seedlings gradually cooled down and hardened in 1 week.

Suitable planting time

Before planting, 2,500kg of decomposed organic fertilizer, 0/00kg of decomposed cake fertilizer, 0/0kg of urea/kloc, 50kg of calcium superphosphate, 0/5kg of potassium sulfate/kloc, or 0/00kg of potassium sulfate high-efficiency multi-element compound fertilizer/kloc-were applied per mu. Combined with fertilization, 2 kg of 3% phoxim granules and 2 kg of 50% carbendazim wettable powder were applied per mu to control underground pests and disinfect soil. 1 One month before planting, make two beds in a 5-meter-wide greenhouse with a width of 2 meters and a 30-cm-wide ditch in the middle. From late February to March, the primary selection is to plant in sunny morning, with a spacing of 80 cm per border 1 row and about 330 plants per mu. After planting, water the living trees, cover them with plastic film, build a small arch shed on them and cover them with grass at night.

Temperature and humidity management

Within 10 days after planting, heat preservation management is the main method, and the greenhouse temperature is kept at 25 ~ 32℃ during the day and 18 ~ 20℃ at night. When the greenhouse temperature exceeds 35℃, it should be properly ventilated to cool down. After sitting on the melon, properly increase ventilation. The greenhouse temperature during the expansion and maturity of melon is maintained at 25 ~ 32℃ during the day and at 15 ~ 20℃ at night. The small arch shed was demolished in mid-April. Pay attention to ventilation after the temperature rises in May, and open the skirt film and the top film to cool down at noon on sunny days. In summer, the edge film is removed, leaving the top film to replenish water. In August, the temperature is high and the transpiration of plants is large, so it is necessary to control the water and temperature scientifically.

Plant regulation

Pruned three vines. When the main vine is 60 cm long, two robust lateral vines are selected in 3 ~ 5 nodes, and all other lateral vines are removed to reduce nutrient consumption. After the melon is set, the weak branches, diseased branches, old leaves and diseased leaves are removed to facilitate ventilation and light transmission. Choose a sunny afternoon to press vines with clods.

Guo Hua management

When the size of melon eggs is 12, choose 1 ~ 2 melons per plant. When the diameter of melon is 1.2 cm, the deformed melon and surplus melon are excluded, with an average of 330 melons per plant 1 melon. Turn the melon after sitting 1 time 1 day, and pad the melon with dry straw or fruit. When the first batch of melons are 7 ~ 8 ripe, the second batch of melons is selected from the newly grown vines in the base, and the remaining amount of melons is determined according to the growth of melons and vines. When vines grow vigorously, there will be more melons, otherwise there will be fewer melons. The temperature is high in autumn, so the position of raising melons should be postponed appropriately. Generally, there are two melons left after 20 festivals. When there are too many melons in the third and fourth batches, the fruits should be thinned properly to ensure the quality of melons.

Control pests and diseases

Pay attention to the prevention and control of watermelon damping-off, damping-off, Fusarium wilt, leaf blight, downy mildew, anthracnose, powdery mildew, aphids, red spiders and other pests and diseases.

Timely harvest

Harvest the first batch of melons 37 ~ 40 days after the female flowers open, and then harvest every 30 days 1 time. When picking the first crop of melons, some of the second crop of melons are already seated. Be careful not to pull the vines too much.

Edit this paragraph

control of insect

Host (of parasites)

In the field, it mainly harms melon seedlings, cruciferous vegetable buds, tender roots and strawberries. I like to eat leaves such as rape, mustard, Chinese cabbage, tomato, cucumber, pumpkin, gourd, soybean, cowpea, amaranth, spinach, lettuce and edible fungi.

The characteristics of damage are that buds and tender roots are damaged, resulting in lack of seedlings and broken ridges, and berries are eaten into holes when damaged; The green part of melon seedlings often doesn't grow vines after being damaged. It has a certain impact on production.

Morphological characteristics: Adult is 10- 14 mm long and 5-6 mm wide. 5mm, rectangular, *** 13 nodes, taupe, with 1 pair of linear antennae on the head; The chest has 8 segments, each segment has 1 pair of feet, the abdomen has 7 pairs of abdominal feet, and there are two flaky protrusions at the end of the tail segment. The back of the female adult is dark brown, with faint yellow-brown moire, and each trailing edge has a white edge, while the male insect is darker in color. Oval to ovoid, yellowish brown. The newly hatched larvae are white and translucent, about 1.3- 1.5 mm long and 0.5-0.8 mm wide, and then gradually become deeper, with the appearance similar to that of adults, but different in size and body color.

Life habit: This insect is viviparous and can move freely to feed after leaving its mother. After feeding, the body wall darkens and the body becomes bigger. Every once in a while, it needs to burrow into the soil to molt, and each female can reproduce 1 10. After hatching, the larvae mostly gather with the female adults, begin to live independently after about 1-2.5 months, and mature after 1 year. At 2 1-22 in the evening, it is most active at 7-8 in the morning, and it also comes out on cloudy days. The seedlings and fruits attached to the ground are vulnerable, easy to turn into rotten grass, with negative phototropism and suspended animation, and immediately curl up into a "watermelon" shape after being frightened.

In addition, there is a watermelon worm in China, whose scientific name is Porcellio scaber Latreille, also known as the wife of the hamster. Widely distributed indoors and in damp places, it also harms rape in the field.

Prevention and control methods (1) The vegetable fields near the village and the edges of ponds and gullies should be protected. No weeds are left in the field, and rotten grass is piled up in the ridge to trap and kill. (2) Avoid applying organic fertilizer with insufficient maturity in vegetable fields. (3) Combined with the prevention and control of underground pests, when a large number of pests are found in rape seedling stage, 25% Aikasi EC 1500 times or 20% insecticidal WP 2000 times and 10% imidacloprid WP 2500 times are sprayed.

The damping-off disease is the main disease of watermelon seedling stage, which is widely distributed and can cause the death of big seedlings. Especially in the nursery, it is the easiest to suffer.

1. The parasitic effect of symptom collapse pathogen is weak, and it can only invade when the seedlings are weak or the young stems are not corked. At seedling stage, waterlogging spots were produced at the base of seedling stem, and then the spots turned yellow-brown and shriveled into lines. The disease develops rapidly, the seedlings collapse before cotyledons wither, and the surface contacting the diseased part is easy to fall off after pulling out, and the disease under cotyledons becomes a neck card. Sometimes before the seedlings are unearthed, the embryonic stems and cotyledons have generally rotted. Sometimes the appearance of seedlings is the same as that of healthy seedlings, but they are stuck on the ground and cannot stand upright. Examining the diseased seedling, we can see that the stem base has contracted like a line. When the humidity is high, a layer of white mycelium will grow on the surface of the affected area and its surrounding soil.

2. The pathogen is pythium melonis (eds. ) fitzp. Belongs to pythium. The hyphae are colorless and septate. Swimming sporangium is formed in asexual stage, and spherical oospores are formed in sexual stage.

3. Pathogenic regularity Pathogens overwinter in 12- 18 cm topsoil, and the suitable ground temperature is 10℃. Low temperature is not conducive to the growth of the host, but the bacteria can still move. When the nutrients in the cotyledons of seedlings are basically used up and the new roots are not yet solid, it is the susceptible period. In case of rain and snow, cloudy day or cold current, the disease is more frequent.

4. Pollution-free prevention technology

(1) The nutrient soil in YEATION is disease-free new soil for seedling raising, or the soil for seedling raising is disinfected, or the medicinal soil made of 50% carbendazim wettable powder 0.5 kg and fine soil 100 kg is sown and covered.

(2) Strengthen seedbed management. Select the land with high terrain, low groundwater level and good drainage as the seedbed, and water the soles of the feet once before sowing to control the humidity of the seedbed. Organic fertilizer or compost must be fully decomposed when it is used as the bottom fertilizer of seedbed. After planting, water should be less in the early stage. If it is a greenhouse, it should be ventilated and dehumidified in time.

(3) For chemical control after emergence, 800 ~ 1 1,000 times of 58% toxic manganese zinc wettable powder, 800 ~ 1 1,000 times of 25% toxic metalaxyl wettable powder or 600 ~ 800 times of 40% ethyl aluminum phosphate wettable powder can be sprayed. Or 500-800 times of 70% glyphosate-manganese-zinc wettable powder, or 800- 1 0,000 times of 58% amine-manganese-zinc wettable powder, or 800- 1 0,000 times of 72% bankdew wettable powder, generally sprayed once every 7- 10 days. After each spraying, the outdoor air should be combined to reduce the humidity in the shed, so as to achieve better control effect.

withered

Watermelon Fusarium wilt, also known as vine cutting disease and Fusarium wilt, is widely distributed. Its incidence is generally around 5%, but also more than 30%, or even not produced.

1. Symptoms Watermelon will get sick during the whole growth process. Watermelon buds are damaged, which will rot and die in the soil and cannot sprout. After emergence, the disease occurs, the top is dehydrated, cotyledons and leaves droop, stems and vines shrink, brown and collapse; The diseased vine comes on, the base turns brown, the stem bark cracks longitudinally, often accompanied by resin glue overflow, and turns red and black after drying. Cross-cutting the diseased vines, and the vascular bundles are brown. In the later stage, the cortex of the diseased plant fell off, the xylem was broken, and only brown fibers were seen in the root rot. When the weather is wet, powdery mildew is common in the affected area, that is, the meristem and robe ball of pathogenic bacteria seedlings.

2. The pathogen is Fusarium oxysporum F. niveum (E.F. Smith) Snyber et Hansen, belonging to Hemiptera subfamily.

3. Law of incidence This disease is a soil-borne disease. Pathogenic seedlings mainly overwinter in soil and sick people, and spread through infected seeds, soil, fertilizer, irrigation water, insects and people. The pathogen invades from the top cells of the root wound or root hair of the host. When the seeds with the pathogen germinate, the pathogen can directly invade the young roots. The onset of summer watermelon began in the middle and late June, and the peak period was from mid-July to early August. The main factors of this disease are temperature and humidity. The disease can occur at 8-34℃, 24-32℃ is the optimum temperature for infection, and 16- 18℃ is the most common seedling stage. It is more common in the climatic conditions of sunny days when it is dry or rainy after rain. In addition, slightly acidic soil and partial application of nitrogen fertilizer are more conducive to the occurrence of diseases.

4. Pollution-free prevention technology

(1) Select disease-resistant or disease-tolerant varieties, use disease-free seeds or sterilized seeds, and collect seeds from disease-free fields. Sterilize the seeds. Before sowing, seed is dressed with 50% carbendazim wettable powder which accounts for 0.3% ~ 0.4% of the seed weight, or soaked with 500 times of 50% carbendazim wettable powder 1 hour.

(2) Strictly selecting nutrient soil and disease-free soil for seedling raising, and using new soil or sterilized soil as nutrient bowl for seedling raising can reduce the infection of germs at seedling stage.

(3) Reasonable cultivation management, improving plant disease resistance, advocating paddy-upland rotation, applying decomposed base fertilizer, timely topdressing phosphorus and potassium fertilizer, timely ventilation and reducing greenhouse humidity. Flood irrigation is not allowed to prevent premature senescence of plants and natural cracking of stem base due to uneven soil water supply. When the disease occurs, it is necessary to control the water, remove the diseased plants in time, completely destroy or bury them, and disinfect the soil with lime.

(4) Disinfection of soil seedbed: 8 grams of 50% carbendazim per square meter is used to treat the border surface. Before planting, 50% carbendazim wettable powder (265,438+0 kg) was used every 667m, mixed with 30kg of fine dry soil, and then evenly sprinkled into the planting hole. In the hot summer season, the soil is disinfected by solar energy, that is, after harvest, the soil is turned over, watered, covered with plastic film, and then the shed is closed 15 ~ 20 days. The surface soil temperature can reach above 70℃, which has a good control effect on soil-borne diseases such as Fusarium wilt and nematodes.

(5) Grafting seedlings with black-seeded pumpkin or gourd as rootstock.

(6) At the initial stage of chemical control or before the onset of disease, the roots were irrigated with 3000-6000 times of 10% world high water dispersible granule or 50% wettable powder 1000- 1500 times of liquid, and each plant was irrigated with 0.25 kg of liquid medicine every 5-7 days continuously.

anthrax

Anthracnose is one of the important diseases of watermelon, which occurs everywhere, especially in rainy weather and rainy areas in the south, and is the main reason that affects the stable and high yield of watermelon. This disease not only harms watermelon, but also harms melon.

1. Symptoms Watermelon leaves, vines and fruits can all get sick. At first, the diseased spots on the leaves are round pale yellow water stains, then turn brown, with purple-brown edges and light brown in the middle, with concentric wheel lines and small black spots, and the diseased spots are easy to be perforated. The diseased spots on petioles and vines are spindle-shaped or rectangular, which are yellow-brown at first and then brown. When the fruit is damaged, it is a small dark green oil spot at first, and then it expands into a circle with a slight depression in dark brown. When the air humidity is high, an orange sticky substance grows on the diseased spots, and when it is serious, the diseased spots are contiguous and watermelons rot.

2. The pathogen is [Colletotrichum rotundum (Berk,&; Montana) ARX, alias gourd anthracnose (pass. ) hey. et halst。 ], the small black spot on the lesion is umbilical. Conidia are ovoid or oblong, colorless single cells, with granular inclusions, bristles scattered in conidia, brown, pale at the top and separated.

3. Pathogenic law: Pathogens mainly attach to the residue of the host and stay in the soil for the winter. Seeds can also carry bacteria, and the germs on seeds can survive for 2 years. Under suitable conditions, germs spread through the splash of rain or irrigation water, excessive application of nitrogen fertilizer, poor drainage, poor ventilation and light transmission, and continuous cropping land are all serious. Watermelons harvested in seriously ill fields or after rain will also get sick during storage and transportation.

4. Pollution-free prevention technology

(1) to breed disease-resistant and disease-tolerant varieties. Generally speaking, thick-skinned melon (cantaloupe type) is prone to disease, while thin-skinned melon (common melon) is more susceptible to disease.

(2) The nutrient soil nursery in YEATION should be rotated with non-melons for more than 3 years to prevent the soil from carrying bacteria, and the seedbed soil must be disinfected if it cannot be rotated.

(3) seed treatment: the seeds for production can be soaked in warm water at 50 ~ 565,438+/-0℃ or dressed with 50% carbendazim powder which accounts for 0.3% ~ 0.4% of the weight of the seeds; Or soak the seeds in 200 times formalin solution for 30 minutes, and rinse with clear water to accelerate germination.

(4) Agricultural measures and non-melon crop rotation for more than 3 years. Adopt formula fertilization and apply fully decomposed organic fertilizer. Pay attention to leveling the land, preventing water accumulation in the field, timely draining after rain, and reasonable close planting. Cucumber should be removed in time after harvest.

(5) At the initial stage of the disease, 75% chlorothalonil wettable powder, 80% mancozeb wettable powder, 50% thiophanate-methyl wettable powder, 500-700% carbendazim wettable powder or 10% can be used in chemical control greenhouse or open field.