When Chinese cabbage is planted, what are the characteristics of being harmed by leafhoppers? How ca

The characteristic is that the rhizome of Chinese cabbage, there are different degrees of spots on the leaves, and there are moldy substances, obviously soft, the way to reduce the harm is to use pesticides, and to water, strengthen the volatilization of medicinal properties, and then go to hoe and ventilate.

When planting Chinese cabbage, the harm of leafhoppers is that it will eat the leaves, resulting in a decrease in water and nutrients, and the Chinese cabbage does not grow large, so it is necessary to use pesticides in advance and reduce the temperature to reduce the harm.

The leaves will be mottled, which will also cause the leaves to appear yellow, and the leaves will dry out. In normal times, it should be watered and fertilized in time to ensure sufficient sunlight, and some nutrient solution should be sprayed regularly to ensure the fertility of the soil.

There will be a lot of black spots on the leaves of Chinese cabbage, the leaves will turn yellow, they will not grow much, and pus will come out of the roots. Spray pesticides at the time of planting so that the harm can be reduced.

Leafhoppers feed on young shoots, young leaves, flower spikes and young juice with adults and nymphs, causing wilting of shoots, distortion of young leaves, loss of green leaves and flower and fruit drops when severe. Honeydew secreted by adult worms can induce soot disease and affect photosynthesis.

Chinese cabbage is susceptible to the harm of black rot in the planting process, this bacterial disease is very harmful to the planting of Chinese cabbage, which directly affects the quality and yield of Chinese cabbage, black rot is also called hemiplegia, which is a very serious disease that harms Chinese cabbage. So how can we effectively reduce the harm of this bacteria?

The first thing to do is to reduce the black rot bacteria in the soilBefore planting Chinese cabbage, we must clean up the weeds, diseased plants and dead leaves in the soil in time, and it is best to burn or bury these diseased residues to prevent pathogenic bacteria from overwintering in the soil.

The soil should be turned deeply, and the large pieces of soil inside should be broken up to loosen the soil, and then covered with mulch, and the weather should be exposed to the sun for a week, so that the soil is deprived of oxygen to kill bacteria and pests.

Carbendazim can also be diluted with water and poured into the soil for disinfection and sterilization, generally black rot can survive in the soil for a year, so it is best not to crop together with cruciferous vegetables, you can plant eggplant, cucumber and other vegetables, which can reduce the bacteria in the soil.

Second, choose seeds that are healthy and not contaminatedIn this way, the infection of black rot can be eliminated at all, and if it is uncertain whether it has black rot, the seeds can be sterilized. You can soak the seeds in cold water for 10 minutes, and then soak them in hot water above 50 degrees for about 30 minutes, black rot will die if it exceeds 50 degrees, so the water should not be too high, otherwise it is easy to scald the seeds to death.

Generally, Chinese cabbage is selected for seedling transplanting, and the distance between the cabbages should be ensured when the value is fixed, so as to ensure that the cabbage will not be too crowded during the adult period, which is not only conducive to the rapid growth of cabbage, but also conducive to spraying pesticides and insects. Reasonable watering and fertilization, it is best to choose a morning watering when the weather is clear.

Have enough nutrientsIf the fertilizer is insufficient, it will reduce the development and growth of cabbage, and the disease resistance will be reduced and cause pests and diseases, so fertilization should be carried out with the growth of cabbage, and the basal fertilizer in the soil must be sufficient.

IfIf you find that you have black rot, you must remove it in time, and disinfect the soil and the surrounding cabbage and use chemicals to prevent and control itIf black rot is not timely, it will break out in a large area.

By spraying a certain amount of pesticides to stop the loss in time, it can also be moved to the greenhouse for breeding.

I think that when Chinese cabbage encounters black rot infestation, it should be sprayed with pesticides in time, and farmers should often inspect Chinese cabbage during the growth period, which can effectively reduce the harm.

If you want to reduce the harm, then you should use pesticides, and you should also have a good environment for Chinese cabbage.

The vegetables planted are easy to be bitten by insects, indicating that no pesticides have been applied. It represents more green and healthy, if the insect infestation is relatively large, you can also spray some pesticides to kill insects, which is also the best way to remove insects in vegetable planting at present. If you are not too troublesome, you can also use the leafy vegetables grown in the countryside are prone to insect pests, and when the leaves are serious, the leaves are full of holes, and the leaves are full of feces pulled by the insects of the cabbage insects, and the vegetables have no edible value at this time.

The prevention and control of insect pests must be early, because there are eggs of pests everywhere, and it is inevitable that there will be insect pests in only planted vegetables, so pesticides and insecticides are indispensable. Although it is not very serious, it can be used manually to eliminate pests, but it is difficult to cure the root cause, after all, after the occurrence of insect pests, there will definitely be insect eggs, and manual removal can only eliminate some adult insects, although I am in the countryside, and I have also planted vegetables, but I really don't understand if I don't put medicine, but the soil method is soaked in lime water, and the plant ash seems to be able to cure some kind of disease, sprinkled on the top of the vegetables, not the soil that puts the roots, I have only seen it, I don't know your situation, whether you can grow vegetables people will know, Therefore, pests cannot be avoided.

<>, some people will say that the vegetables that have been bitten by insects are healthier and safer, and the ** of this statement is that they themselves think that the vegetables bitten by insects are not sprayed with pesticides, or that there are very few pesticides sprayed, which is not a science ** You plant mainly leafy vegetables, leafy vegetables are indeed very attractive to insects, especially cabbage worms are a lot, the way to deal with cabbage worms, in addition to manually catching insects is spraying pesticides, but I see that your vegetable planting area is not large, I will introduce you to a good way to prevent insects, It is normal for the fields to be covered with mesh and open spaces to grow vegetables that are susceptible to insect infestations.

So after all, there are still a lot of pests, such as the eggs left on cultivated land, the pests migrated from other areas, and the pests that hide and inhabit in grass, trees and other areas, etc., are all insect pests.

It can cause the yield of Chinese cabbage to decrease, and the quality will also change to a certain extent, which is very bad, because these flies and insects especially like Chinese cabbage.

The adult flies lay eggs in the leaf tissue, and the hatched larvae feed between the mesophyll and the epidermis, forming a curved white linear food mark. When the damage is serious, the leaves are covered with latent marks, causing the leaves to yellowing or scorching, and they are inedible. 1. The annual occurrence generation of the vegetable submarine fly is unknown, and it is estimated that the insect has at least 20 generations of occurrence in Taiwan.

2. The peak period of occurrence of vegetable submarine flies is April and June every year. 3. The larvae of the vegetable submarine fly drill out of the harmful place after they are old and mature, and pupate on the surface of the leaf or bounce into the soil near the surface.

The instar larvae eat the mesophyll on the back of the leaf, leaving a thin and transparent epidermis, and the larvae above the 3rd instar eat significantly more, and the leaves can be eaten into holes or missing carvings, affecting the normal growth and core of Chinese cabbage. If the larvae are wrapped in the ball, the larvae feed on the leaf balls and excrete feces to contaminate the cabbage, reducing the value of the Chinese cabbage. Its wounds are also prone to the occurrence of soft rot of Chinese cabbage.

Pests and diseases of Chinese cabbage seedlings.

The first is whiteflies, leafhoppers, gray planthoppers, blind bugs, thrips, etc., which harm the leaves. The characteristic of the hazard is to suck the sap of the leaves, causing the leaves to fade green, turn yellow, wilt, affect the normal growth of cabbage, and even the leaves or the whole plant die, and can also spread diseases;

The second is the boring leaf-eating pests diamondback moth, heartworm, cotton bollworm, beet armyworm, cabbage worm, etc. The larvae feed on the leaves, and eat the heart leaves and rhizomes, resulting in direct death of seedlings, or the cabbage has no heart, giving birth to tillers, affecting the cabbage core, and the pest secretions seriously pollute the leaves, causing the occurrence of mold disease, so that the cabbage loses its edible value;

The third is underground pests such as ground tigers, grubs, needleworms, etc. biting the roots or outer cortex underground or drilling the column from the root upwards, resulting in the death of aboveground wilting; Fourth, the surrounding environment has migrated into pests such as Tuhuang and crickets, which can eat up the leaves or the whole plant.

Control methods: 1. Remove environmental weeds and reduce the source of insects. If necessary, pesticides can be used in advance to control weeds and insect pests in the environment around the cabbage field.

Second, crickets, locusts, etc., can be used poison bait to prevent and control and cure tigers, cabbage sowing, with 50% phosphine or 48% chlorpyrifos one or two, mixed into 10 catties of chopped fresh vegetables, or fried wheat bran or cottonseed cake powder. The humidity after mixing the dry ingredients should be hand-held but not dripping. The poisonous bait should be sprinkled around the vegetable field or the whole field in the evening, and be careful not to sprinkle it on the cabbage ditch or cabbage seedlings, so as not to cause pesticide damage.

Third, the principle of pest control at the seedling stage of cabbage is: early medication, mixed medication, the use of low-toxicity, high-efficiency and residue-free agents, to be targeted, to treat a variety of pests, reduce the number of drugs, and control the harm before the cabbage seedlings.

Here's how:

1. It is mainly to protect the seedlings, the first spraying of cabbage seedlings is carried out for 2-3 days, the pressure of the sprayer should be small when spraying, and the nozzle should be close to the vegetable seedlings, so that the liquid medicine can penetrate into the soil through the seedlings to achieve the effect of spraying.

2. The number of spraying is determined according to the insect situation, generally about 5 days apart, and if you eat cabbage when you set the seedlings, you must stop the medicine for more than 7 days before you can eat it.

3. Cabbage seedlings are not resistant, and the spraying concentration must be controlled while choosing a good agent, so as not to cause white hearts and burning seedlings.

Formula 1, the use of cypermethrin or other pyrethrin, 15 ml per sprayer water or 10 ml of 5% emamectin benzoate or 5 ml of 20% chlorantraniliprole suspension emulsion; Mix 15 g of 10% imidacloprid, or 50% pymetrozine, or 10 g of 10% dimethoxamin.

Recipe 2: Use 40% chlorant. 4 grams of thiamethoxam aqueous dispersant

Cabbage black rot, also known as hemiplegia, is one of the main diseases of Chinese cabbage, which occurs in cabbage planting areas across the country, mostly in the high temperature and rainy season, in addition to harming cabbage, it also harms cabbage, cauliflower, cabbage, rape, cabbage and other cruciferous vegetables; Let's take a look at the symptoms, occurrence rules and prevention methods of cabbage black rot

1. Onset of symptoms;

Black rot can occur during the growth and development of cabbage. seedling damage; The cotyledons are water-stained and gradually wilt or spread to the true leaves, and the roots turn black, causing the seedlings to wilt and die; Adult plants are damaged, lesions occur on the leaf margins of multiple leaves, at night or at wounds, and gradually develop downward, forming "V" shaped yellow-brown lesions, which expand and spread and become black-brown, resulting in partial or entire leaf decay and death; The pathogen develops along the veins to the petiole and spreads to the stem and root of the plant, and the pathogen will develop down the vascular bundles, resulting in brown dry rot of vascular tubes, bending the leaves like normal, and in severe cases, the leaves die.

Second, the incidence of the disease;

Cabbage black rot is caused by the bacterial infection of the diseased species caused by Xantomonas wild rapeseed and wild rape black rot, the pathogen overwinters through the diseased residues in the infected seeds or red soil or unrotted compost, the growth temperature range of the pathogen is 5 to 38, and the suitable temperature range is 25 to 30, and the suitable environment is suitable. It will become the initial source of infection of cabbage planted in winter and spring protected areas. After the seedlings are planted, the pathogens invade the plants through leaf water holes, stomata or wounds, and spread through irrigation, watering, wind and rain, farm tools, and agricultural operations.

3. Prevention and control methods;

1. Seed treatment; Choose excellent varieties with disease resistance and strong disease resistance, soak the seeds in warm water of 55 for 30 minutes before sowing, and then put them into cold water to cool after taking them out, and then sow them after they are dried in the sun, and you can also use 45% ammonium dyssen water agent to prepare 300 times the liquid medicine, the seeds are soaked in the liquid medicine for 20 minutes, and then you can sow them with clean water after taking them out, and you can sow them after drying, and you can also use 50% copper succinate wettable powder or Fumei double wettable powder of the seed weight to dress the seeds;

2. Agricultural prevention and control; The field of planting cabbage should be rotated with non-cruciferous vegetables for 2 to 3 years, strengthen field management, apply fully rotted farm fertilizer in combination with deep ploughing, timely sowing, reasonable dense planting, timely insect control, timely drainage after rain, timely cultivation and weeding, and timely removal of diseased plants.

3. Pharmaceutical prevention and control; In the early stage of black rot, it is necessary to spray the prevention and control in time, and can use 47% ethylphosphine aluminum wettable powder to prepare 800 times of water solution, or 78% Boer manganese zinc visible powder to prepare 500 times of water solution, or 77% of the wettable powder to prepare 500 times of water solution, or 20% quinoxidone wettable powder with water configuration of 1000 times of liquid, spray once every 7 days, spray 3 to 4 times continuously, the above agents are used alternately, can effectively improve the control effect.

Black rot, also known as hemiplegia, is a serious disease that harms Chinese cabbage. Before planting Chinese cabbage, it is necessary to remove weeds, diseased plants and dead leaves from the soil in time. These diseases are best burned or buried in depth to prevent germs from overwintering in the soil.

Cabbage suffering from black rot must be removed in time, and the soil and surrounding cabbage should be disinfected and controlled with chemicals. If left untreated, black rot can break out on a large scale.

selection of disease-resistant varieties; Adjust the layout of vegetables, rotate crops reasonably, and remove diseased plants in time; Sow early at the right time to avoid high temperatures and aphid rampant seasons;

selection of disease-resistant varieties; In general, the straight type and the green gang type varieties are more resistant to disease. Cultivate the land as early as possible, and apply well-rotted organic fertilizer.

It is cultivated with small high ridges and sown at the right time. Timely drainage after rain, fertilizer and water management should be coordinated to avoid excessive and over-wet soil. Do not flood the heart during the hearting period.

Early elimination of various pests that cause wounds. Such as yellow-striped jumping beetle, cabbage worm, diamondback moth, ape leaf worm, dimin and cabbage night thief moth, etc. Remove diseased strains in a timely manner.

If seriously diseased plants are found in the field, they should be harvested or uprooted in time to reduce the source of disease and prevent the spread. In particular, it should be checked and treated before heavy rain or irrigation.