What are the causes of planting watermelon to cause leaf dryness and shrinkage? How can it be preven

Watermelon cultivation is often infected with pathogens, leaf wilting, reduced yield, and reduced harvest, so it is necessary to effectively prevent it and lay a solid foundation for the strong growth and development of plants.

Watermelon downy mildew is caused by the penetration of hospital fungi by pseudodowny mildew of the subphylum Flagellella, which is spread by air currents and rainwater. Powdery mildew is only harmful to watermelon leaves, after infection, watermelon leaves appear water-stained shape faded spots, and then develop into yellow spots, limited by leaf veins into polygonal yellow-brown spots, when wet, purple-red mold grows at the leaves and other spots, and when the disease is serious, the disease spots combine to cause the leaves to shrink.

Watermelon downy mildew symptoms.

The disease spreads upwards from the lower leaves, and when severe, only the top 3 or 5 young leaves remain. Generally speaking, the temperature difference between day and night is large, rainy, foggy, dew condensation, and diseases are prone to occur.

Symptoms of watermelon powdery mildew leaf damage.

Agricultural prevention and control: When planting and planting strong seedlings, it is strictly forbidden to rob tombs. Please choose a plot with high terrain and good drainage for planting. Apply corrosive organic fertilizers, increase phosphorus and potassium fertilizers, avoid comfortable application of nitrogen fertilizers, prevent plant growth, form shade, and poor ventilation.

Strengthen warehouse management: In greenhouses, greenhouses or mulch-covered cultivation, the temperature and humidity should be strictly controlled, and attention should be paid to well-ventilated light. Adjust the water properly, watering until 12 a.m. on a sunny day, and do not water or flood on a cloudy day. After rain, pay attention to field drainage.

Supplement nutrients to plants: The disease of plants is often related to the imbalance of "carbon and nitrogen ratio" in the body, and strengthening leaf nutrition can improve disease resistance. Urea:

Glucose (or sugar): water = 1: 1:

The ratio of 100 prepared solution, once every 3 5 days, sprayed 4 times in a row, the preventive effect is better.

Pesticide prevention: In order to improve and strengthen the physiological and metabolic function of plants, strengthen the active resistance mechanism of watermelon itself, reasonable mixing of aluminum ethyl phosphorus and potassium dihydrogen phosphate, foliar spraying, and achieve obvious disease prevention effect and yield increase effect. Or use 72% Kelu humidifying powder 700 times, Frick homemade 800 1000 times, 69% amphetamine zinc humidifying powder 800 1000 times, or 1:

: 240 320 times.

The cause is caused by powdery mildew. After months of infection, watermelon appears as a small spot in the shape of a water stain, and then develops into a small yellow spot. Yellow-brown spots that turn into polygons after limiting.

In severe cases, it can cause cucumber leaves to wither. When planting and setting the value of strong seedlings, choose plots with high terrain and good drainage. Use corrosive organic fertilizers to increase phosphorus and potassium fertilizers, and avoid nitrogen fertilizers.

There are two causes of planting watermelon to cause the leaves to dry up and shrink, the first is that it may be tired, there are small insects on the leaves, the second reason may be the lack of water, the solution is to bring the medicine to her when the watermelon is just growing, to prevent small insects on the leaves, and to pay attention to the dry and hot weather, to water the watermelon.

The cause of dry and curly leaves may be the occurrence of pests and diseases in the plant or the dryness caused by too high temperatures. In the event of a disease, plant insecticides should be sprayed evenly on the leaves. If the temperature is too high, water the leaves of the plant in moderation to lower the temperature.

The dry edge of watermelon leaves is leaf blight, which is mainly eroded from the edge of the leaf and the tip of the leaf, and the disease in the lower part is more serious. When the condition is mild, it is necessary to remove the diseased leaves in time and ensure the ventilation of the environment, and in severe cases, it is necessary to spray the diluted meconazole solution. The dry edges of watermelon leaves may be caused by a lack of nutrients, and nitrogen, phosphorus and potassium compound fertilizers need to be applied to alleviate them.

Watermelon leaf edge dry is leaf blight, leaf blight usually breaks out in July and October every year, mainly from the leaf edge, leaf tip and other parts of the erosion, the lower part of the plant disease will be more serious, mostly due to high temperature and humidity, poor ventilation and other reasons.

When the leaf blight of watermelon is relatively mild, it is necessary to remove the diseased leaves in time, sterilize and disinfect them, and then ensure the ventilation of the environment, and give appropriate astigmatism irradiation, and properly turn the soil to ensure the air permeability of the soil. If the condition is severe, diluted distilloconazole solution should be sprayed on the leaves every 7 days**.

The yellowing of the leaf edge of the watermelon may also be that there is no fertilization for a long time, resulting in the lack of nutrients in the seedlings, so that the leaf edge appears to grow and decline, and the leaf edge is yellow.

Applying excessive concentration of chemical fertilizer to the watermelon, or not applying rotten organic fertilizer, will cause the watermelon to burn the roots due to fertilizer damage, so that the edge of the watermelon leaves appear yellow, at this time, it is necessary to water the watermelon, dilute the fertilizer at the roots, and then strengthen the ventilation of the field, so that the watermelon can recover as soon as possible.

What are the causes of planting watermelon to cause leaf dryness and shrinkage? How can it be prevented?

The cause is caused by powdery mildew. After the watermelon is intracted, it appears in the shape of a water stain and then develops into a yellow dot. Yellow-brown spots that turn into polygons after limiting.

When the weight of the Yan Tan plum pants will cause the cucumber leaves to wither. When planting and setting the value of strong seedlings, choose plots with high terrain and good drainage. Use corrosive organic fertilizers to increase phosphorus and reduce potassium fertilizers and avoid nitrogen fertilizers.

Too much rain, lack of oxygen in the soil, anaerobic respiration by the roots to produce alcohol, toxic to the root cells.

Reason 2: You can't lack water when planting watermelons, but you are afraid of waterlogging. If there is too much rain and there is water in the ground, pests and diseases will appear.

The root system of watermelon is drought-tolerant orange bannier, avoid moisture, not resistant to waterlogging, the roots of the melon field rot after waterlogging, resulting in the death of the whole field, and the southern region is rainy and waterlogged, so the southern region should choose the fields with higher terrain, flat, low groundwater level, and easy to drain and irrigate.

1.Seed carriers cause leaf blight The seeds themselves carry bacteria, which is the main cause of leaf blight. 2.

Continuous cropping of watermelon causes leaf blight. 3.Suitable environmental conditions lead to the occurrence of coarse leaf blight The main channel for pathogenic bacteria to invade plants is the stomata transformed from leaf dust.

Loss Brother Town 4Poor cultivation management leads to leaf blight.

Watermelon leaf blight is caused by the fungus Alternaria melonii by the subphylum Alternaria hemiphyta. The pathogen overwinters with mycelium and conidia in the soil surface and seeds, and after sowing watermelon in the following year, the temperature and humidity are suitable, causing the initial infection, and then a large number of conidia occur, which are spread by wind and rain to infect again, resulting in the continuous spread of the disease. The bacterium can grow in the range of 3-45, with 28-32 being the most suitable.

The incidence of the disease is closely related to humidity, when there is a lot of rain and heavy rainfall, and when the relative humidity is high, the disease of nuclear wear is serious; If the humidity is below 70%, it is difficult to get sick. In addition, continuous cropping, planting density, weeds, nitrogen fertilizer application rate, and severe disease.

It can be affected by the environment, it will be affected by the air, it will be affected by the seasons, it will be affected by rain, it will also be affected by the soil.

The main reason for the shrinkage of watermelon leaves is the lack of water in the soil.

The main reason is the lack of water in the soil, the temperature in the greenhouse will rise on a sunny day, the water loss is fast, and the root system is not developed, and it is easy to roll leaves. It may also be that the environment is uncomfortable, it is infected with a viral disease, in which case the leaves will become smaller and blinder, and it will also be curly. Early sowing can achieve early emergence of seedlings, early flowering and setting of melons, so that the development stage is advanced, so that the plant can avoid the disease period or reduce the disease.

Strengthen field management. It is necessary to increase the application of phosphorus and potassium fertilizers to promote the growth of plants, and at the same time to prevent excessive dry welding in the field. Do not tidy up the diseased plants when pruning and pruning, and pull out the diseased plants and bury them deeply after the healthy plants are finished.

Eliminate aphids in a timely manner. Remove weeds in and around the melon field to prevent aphid breeding. Spray aphids in time to control aphids before they migrate.

A small amount of inorganic fertilizer can also be added. Nitrogen, phosphorus, and potassium are indispensable for fertilizers.

How watermelons are maintained

Three-vine pruning is the most commonly used pruning method, when the main vine grows 8 or 9 leaves, in addition to the main vine, two side vines with better growth should be selected. When the melon vine grows to 50cm, press the vine with soil, and press the vine in combination with pruning, and then repeat the operation at intervals of 3 4 sections, and press each branch 2 3 times. When the plant grows to the size of an egg, it means that it will soon enter the swelling period, and then it should be applied to it in time according to the growth of watermelon.

Watering should be in the morning and evening, the temperature is low, and the watering is not easy to damage the watermelon. And after the rain, the stagnant water in the melon field should be discharged in time. After the watermelon is planted, it is necessary to strengthen management, increase phosphorus and potassium fertilizer, and organic fertilizer in time to promote more robust growth, which can improve disease resistance.

It is also necessary to water in a timely manner, and the plot should not be too dry. The diseased plants that are usually sorted out should be completely eliminated to avoid infection with pests and diseases.