What should I do if cucumber leaf burn occurs?

Cucumber is a relatively common vegetable in our life, and in our rural areas of Guangxi, many cucumbers can now be picked and harvested. In the process of planting cucumbers, we often encounter the occurrence of cucumber leaf burning, for example.

If it is not carried out in time, it will lead to a reduction in cucumber yield. So how to prevent cucumber leaf burn?

A brief introduction to leaf burn

Leaf burn disease is a disease of plants, often occurs on cucumber crops, once cucumber is contaminated with this disease, cucumber leaves and stems will turn green, and then appear yellowing, seriously affect the normal development and growth of cucumber, reduce the yield and quality of cucumber, and is very unfavorable to the production of cucumber.

Symptom recognition

After sowing, the air temperature and ground temperature are too low, the seed germination and emergence are delayed, the seedlings are weak, the yellow seedlings are weak, and the orange seeds may fall down and root rot. The edge of the cotyledons of the unearthed seedlings appears white, the leaves turn yellow, and the root system is neither rotten nor long. The seedlings grow slowly, retreat, and the leaf color is light, which is called the edge withered yellow.

Growth is stagnant, the plant does not rot and does not grow, the seedlings wilt, the leaf margins are yellow, and the melons are few and small. When the adult plant is lightly damaged, the leaf tissue fades green and turns yellowish-white. If the temperature is low for a long time, the plant often does not take root or differentiate the flower buds.

In severe cases, part of the mesophyll tissue dies, resulting in the death of some leaves. Severely damaged plants begin to be water-stained and later dry up and die. When the plant is attacked by the cold current, the young tissues are water-stained necrosis, and the yellow-brown water-stained shape is formed along the leaf veins in the middle leaf at the initial stage of damage, and then forms palm-shaped yellow veins.

Methods for treating cucumber leaf burn

First of all, it is necessary to control the water, for the cucumber plant, it is not that the more water, the more beneficial, it is necessary to drain the water in time, otherwise the water will flood the roots for a long time, which will cause the roots to produce alcohol by anaerobic respiration, which will cause root rot, and may also be contaminated with fungi, resulting in the occurrence of root rot.

Secondly, it is necessary to manage the soil, keep the soil pH appropriate, and avoid the soil clumping cucumber roots can not breathe.

Finally, to prevent pests and supplement nutrients, cucumber plant insect control ability is relatively weak, in addition to fixed-point spraying drugs, Ah Kun suggested that you can properly sprinkle some vinegar on the foliage, which can effectively prevent pests from gnawing, so that you can also supplement some nutrients.

When the temperature is high, we should uncover the membranes on both sides of the greenhouse in time to ventilate and ventilate to make the temperature in the shed balanced.

To control the temperature. Leaf burning disease caused by high temperatures mainly occurs when growing in greenhouses, and leaves that are close to or in contact with greenhouse film are prone to growth. This is mainly due to the high temperature of the greenhouse.

When the temperature in the greenhouse reaches more than 40 degrees and the temperature is lower than 80%, it is easy to cause high temperature damage, especially when the sun is strong. When growing cucumbers in greenhouses, they must be ventilated and cooled down in time. During the day, the temperature inside the greenhouse should be kept below 30 degrees and the ground temperature should not be higher than 25 degrees.

At night, the temperature should be controlled at 18-20 degrees, so that cucumbers can grow better in such a temperature environment and are not suitable for overgrowth.

You can control the moisture first, maintain the pH of the soil, carry out an appropriate amount of fertilizer, and sprinkle some vinegar to prevent pests.

1. Element-deficient yellow leaves: Element-deficient yellow leaves are divided into two situations: middle and lower old leaves and middle and upper young leaves.

The middle and lower leaves are yellow, and most of the missing elements are the elements that are easy to be reused in the plant, such as nitrogen, potassium, magnesium, zinc, etc. (1) The growth of the whole plant is resisted, and the whole leaf lacks green first, which is nitrogen deficiency. The control countermeasure is to spray urea solution 2 3 times on the foliar surface.

2) The whole plant growth has no obvious resistance to the loss of green and yellow, the loss of green and yellow between the leaf veins, the leaf edge is green, or there are residual green spots, no curl, magnesium deficiency. The control countermeasure is foliar spraying of 1% 2% magnesium sulfate solution. (3) There is no obvious inhibition of plant growth, and the leaf edge loses green to necrosis, and sometimes there are green to necrotic spots on the leaves, which is potassium deficiency.

The control countermeasure is to spray potassium dihydrogen phosphate solution 2 3 times. (4) Plant growth without obvious resistance, whole.

Leaves that are green to necrotic spots or streaks are zinc deficient. The control countermeasure is foliar spraying of zinc sulfate solution.

The middle and upper young leaves are yellow first, and most of the missing elements are elements that are not easy to be reused in the plant, such as calcium, sulfur, iron, etc. (1) The growth point is dead, and the leaves lose green, shrink to necrosis; The root system is underdeveloped, and it rarely bears melons, which is calcium deficiency. Control measuresFoliar spraying of calcium chloride solution 2 times a week.

2) The growth point does not die, the leaf color is light green, and the stem is small and lacks sulfur. The control countermeasure is foliar spraying of 1% potassium sulfate solution. (3) The growth point does not die, and the leaf color is yellow and white, which is iron deficiency.

The control countermeasure is foliar spraying of ferric sulfate solution.

2. Downy mildew yellow leaves: downy mildew is a common and serious disease during the growth period of cucumbers. At the seedling stage, the leaves turn green and yellow, and finally die.

At the adult stage, the leaves are diseased, and they begin to appear water-stained yellow round spots on the back of the leaves, especially in the morning, and gradually develop into yellow-brown polygonal lesions with yellow-green edges. Under high temperature conditions, a gray-brown mold layer grows on the back of the lesions, and in severe cases, the lesions become patches, the whole leaves are yellow-brown, and the leaf margins are curled and wilted. The control countermeasure is to use 500 times of Ruixin, manganese-zinc 58% wettable powder or 75% chlorothalonil wettable powder, 50% lysohydrate wettable powder 600 times liquid for foliar spraying, once every 7 days, generally spraying 3 4 times.

3. Yellow leaves of Fusarium wilt: Fusarium wilt is commonly known as "dead seedlings". In the early stage of the disease, some leaves wilt at noon, and can recover in the morning and evening, and do not recover after a few days.

The leaf color gradually changes from yellow-green to yellow-brown, and gradually expands to the whole plant from bottom to top. The main vine near the ground is brown and water-stained and rotten, thinning or longitudinally cracked, gradually drying up, and the whole plant is dead. Amber gelatinous flows out of the diseased part of the rhizome, and when the temperature is high, white or pink mold is produced on the surface, and when the stem or taproot is broken, the inside can be seen to turn brown.

Prevention and control measures: It is to irrigate the roots with 500 times of 50% carbendazim wettable powder, or 500 times of 500 times of methyl tobuzin wettable powder, not less than 250ml of each plant, irrigated once every 5 6 days, and irrigated 2 3 times.

Remove the diseased leaves and spray carbendazim on the line.

No ** can not be accurately judged, cucumber fruiting period requires a large amount of water, suspected lack of water or bacterial wilt.

Bacterial wilt is also known as bacterial wilt, grafting cucumber in the shed is common, this disease is very harmful to production, and the whole greenhouse plant dies when the disease is serious. Cucumber bacterial wilt disease occurs quickly on grafted cucumbers, slower in self-root cultivation, can occur at seedling stage and adult plant stage, and seriously occurs at flowering and melon setting stage.

At the beginning of the disease, the stem at the base of the plant shrinks and becomes thinner, and the lower leaves are dull and wilted, which is obvious at noon. The disease progressed gradually, the shrinking stems and vines expanded upward, and the leaves gradually wilted upward, as if lacking water, and the whole plant died after 3 5 days.

Prevention and control: 1. It can be rotated with non-melon vegetables for more than 2 years.

2. Remove diseased leaves during the growth period and after harvest, and bury them deep in time. Drain water in time in rainy days, and watering should be less and more frequent to prevent flooding. Increase the application of organic fertilizer and reduce the amount of chemical fertilizer.

Potassium fertilizer can be increased during the peak flowering and fruiting period, and potassium dihydrogen phosphate can be sprayed on the foliar surface to improve the disease resistance of plants.

3. In the early stage of the disease, use 60% amber in time? Irrigate roots with 500 times of acephosphine aluminum, or 4000 times of 72% agricultural streptomycin wettable powder, with 150 200 ml per plant. Irrigate the roots every 10 days, 2 3 times in a row.

Cucumbers are a common vegetable in life. Because it is rich in nutrients and has the effect of improving the body's metabolism, it is often used in the diet. What's more, many people raise cucumbers at home, but many people encounter the problem of cucumbers shrinking before they grow.

1. How do cucumbers shrink when they don't grow? Cucumbers should be fertilized reasonably during the growth period. If they are left unfertilized for a long time or lack nutrients, they will shrunk when they grow up.

Generally speaking, it is recommended to fertilize cucumber every 7 to 10 days during the growing season, and foliar fertilizer can also be sprayed appropriately to be more conducive to its growth and maturity. If cucumbers shrink when they grow, it may be caused by pests and diseases. In this case, we can only pull out the badly damaged cucumber to prevent the spread of the disease.

At the same time, spray some fungicide on it. 2. Why do melons wither? Cucumbers are planted in many families, and the reason why they wilt before they grow is a problem.

Most of them are caused by lack of water. It needs a lot of water during its growing season, and hot weather can stunt its growth. If nutrient deficiency can also lead to this, we should fertilize it regularly during its growing season.

If cucumbers are infected with pests and diseases, the fruit will shrivel when it grows up. It is advisable to spray chemicals in a timely manner. 3. How can cucumbers grow well?

The root system of pure wild cucumber is relatively shallow. Organic fertilizer should be used as the base in cultivation to improve soil permeability and fertilizer supplementation. The soil nutrient absorption capacity of cucumbers is lower than that of melons, and top dressing requires "eating less and eating more", and the same is true for water requirements during the fruiting period.

The fertilizer is a water-soluble fertilizer for the fertile field. Start with the stems and leaves. During the growing season, depending on the growth, it is best to prune and pinch the branches in the afternoon.

Keep 12 leaves after fruiting and pinch off the tendrils to reduce unnecessary nutrient consumption. Temperature control. Generally, during photosynthesis, cucumber respiration above 32 will be enhanced, but the conversion rate will be reduced.

When the temperature exceeds 40, the flowers will fall and photosynthesis will decrease, which is not conducive to fruit growth. Pest control. Proper spraying of pesticides to ensure healthy growth of cucumber plants, thereby increasing yields.

Identify the root cause of the disease.

If you want to treat the problem of yellowing of cucumber leaves, you need to figure out what causes it. We must carefully observe the symptoms of yellowing leaves, find out what factors are at work, whether it is environmental factors, or operational factors, or fertilization or what problems, whether it is a deficiency type of yellow leaves, downy mildew yellow leaves, wilt yellow leaves, etc., or other diseases, we must find out clearly, so as to prescribe the right medicine.

end fertilizer control.

Appearance: Yellowing of the edges of the leaves, salinization of the soil, etc.

Causes: Too much fertilization.

Control measures: In order to reduce the concentration of soil solution, we need to water many times, but pay attention to the amount of water, do not water too much at one time, in addition, we should pay attention to scientific fertilization, control the concentration of fertilization, it is best to use biological fertilizer (humic acid fertilizer can also be).

Appearance: Element-deficient yellow leaves.

Reason: Long-term lack of fertilizer.

Control measures: Due to the different kinds of elements contained in the fertilizer, the corresponding fertilizer spraying is selected according to the different positions and appearances of the manifestation of the deficiency yellow leaves. For example, potassium deficiency, nitrogen deficiency, and calcium deficiency need to be sprayed with different fertilizer solutions to prescribe the right medicine.

end external factors.

Prevention and control measures: we must learn to use effective control to reduce the impact of external environmental mutations on cucumber leaves, such as trying to control the environmental temperature, greenhouse farming, greenhouse farming, etc., to effectively reduce environmental damage.

Appearance: Yellow-green mottled leaf surface.

Causes: Pest and disease effects.

Control measures: Some fungicides can be sprayed (pay attention to the corresponding pest species, so as not to negatively affect the normal development of cucumber plants).

Appearance: The leaves are generally yellowish and slightly wilted.

Cause: Overwatering (possibly).

Nitrogen deficiency fertilizer 2 Deficiency of micro fertilizer (such as green loss caused by iron deficiency) 3. Caused by fungi and bacteria (such as downy mildew), etc. Symptomatic application can be applied according to the seedling condition and condition! It should not be caused by lack of water, the marginal leaves are slightly yellow, if there is no sunlight for a long time, the whole leaf will fall, the two biggest possibilities:

1 is caused by the lack of fertilizer, you can add some iron-containing fertilizer, 2, another one, if the fertilizer is too large, the new leaf tip yellow or the flower yellow, you can stop making the fertilizer can be rinsed with water!

A vegetable garden cannot be planted with cucumbers for several years, which will lead to an imbalance of soil nutrients, so change vegetables every three years, and tomatoes, eggplants, etc. can be planted in turn;

It is likely to be leaf blight, and it should be sprayed evenly on the leaves of the plant with a special insecticide for plants in a timely manner, and it should not be watered during the medication, otherwise there is no effect, and it can be sprayed several times to consolidate it.

Apply more fertilizer. Water more. You can go to a professional place for a consultation, and they can also give you good advice.

This is the lack of trace elements of the element, supplement the water-soluble micro fertilizer seedlings to make money, containing manganese, zinc, boron and other elements, high content, good fertilizer effect, quick effect, such as manganese can promote the development and growth of cucumbers, promote the formation of cucumber chlorophyll, lack of manganese cucumber plants dwarf, narrow and short leaves, serious dark brown spots, zinc, boron, copper and other elements can also be conducive to the growth and development of cucumbers.

You can buy some pesticides to beat cucumbers, tell the merchant according to the corresponding **, the merchant will match you with the corresponding pesticides, you just need to bring it back to fight.

If you want to remedy it, you must determine the cause, if it is because of pests and diseases, you should buy pesticides to spray, if it is because of malnutrition, you should strengthen fertilization.