Types and characteristics of pests and diseases, identification and control of pests and diseases

1) There are three external manifestations of viral diseases of vegetables that damage the top young leaves:

1) The mosaic leaves appear to be shrunken leaves with yellow-green spots. The yellow flowers and leaves are particularly bright, and the green flowers and leaves are dark green. The yellow parts are concave downwards, and the green parts are convex upwards.

2) The leaves are slender and elongated, the veins are upward, and the heavy ones are linear.

3) Leaf curling is manifested as a twisted blade that curls inward.

2) Viral diseases of vegetables that damage fruits, mainly manifested in stripes on fruits at the ripening stage. For example, tomato stripe spot virus disease appears bluish-white on the shoulders of the fruit and then gradually turns rust-colored. The fruit is cut open with a knife, and there are brown streaks on the outside of the skin.

Another example is pepper stripe spot virus disease, which turns yellow from the tip of the fruit upwards, with short brown streaks on the yellowed parts and inward depression.

There are about 200 kinds of viral diseases of vegetables, and about 50 kinds of common diseases, accounting for about 5 of the whole vegetable diseases. Its characteristics are: few types; The harm is great, which can reduce the yield of vegetables by 3-5 percent, and the severe is extinct, which is a devastating disease of vegetables; It is widely distributed, almost all plants have viral diseases, and even one plant has 1-4 viral diseases at the same time; It is difficult to prevent and treat, and there is no specific drug.

3) Common pests and diseases.

1) Moths.

It belongs to the lepidopteran moth family, except for a few species of bud and shoot of the plant, the larvae of most species often roll the leaves into cylindrical insect buds, hide in them to feed on the leaves, the light ones make the flowers and trees lose their ornamental value, and the heavy ones eat up the leaves, causing the plants to wither. The common species on garden plants include boxwood silk borer, cotton curly leaf borer, yellow-winged leaf borer, grassland borer, etc.

2) Inchworms.

Lepidoptera moths are a kind of large pests on garden plants, often outbreaks, and can eat up the leaves in a short period of time. The larvae are called "inchworms, the body is bent and stretched like a cloth when walking, and the gastropods are fixed on the tree body when they are resting, and the body is straight and obliquely extended, mimicking."

Such as twigs. Most species of larvae eat leaves, and a few species eat young shoots, causing leaves to be hollow or missing, and in severe cases, the leaves are eaten up. Common species include Acacia inchworm, Silk cotton Mujin inchworm, Robinia pseudoacacia eyebrow inchworm, Ligustrum ligustrum moth, etc.

3) Stinging moths.

It belongs to the lepidopteran moth family, and the larvae are commonly known as spicy seeds.

Slug-shaped, with a stinger on the body surface.

Palpable**, itching and pain abnormal. The hatched larvae swarmed and ate the lower epidermis and mesophyll of the leaves, and the upper epidermis and leaf veins remained. When it is slightly larger, it eats inward from the leaf margin, and when it is severe, the leaves are eaten up, leaving only a small part of the leaves and petioles. Common species include yellow thorn moth, green thorn moth, mulberry brown thorn moth, flat thorn moth, etc. Wait a minute.

1. Most of them feed on trees and lawn leaves, and when they are rampant, they can eat up the leaves, weaken the tree potential, and provide suitable conditions for the invasion of stem boring pests such as longhorn beetles and small silverfish, which not only affects the normal growth of plants, but also reduces the beautification function and ornamental value of plants. Such pests mainly include lepidopteran puponicature, stinging moth, large silkworm moth, inchworm moth, moth, leaf moth, boat moth, American white moth, Acacia japonica moth, butterfly, leaf bee of Coleoptera, leaf wasp of Hymenoptera, etc.

2. Stinging and sucking pests are a large group of garden plant pests. They are small, often not obvious in the early stage of damage, easy to be ignored by people, but the number is very large, often live in groups on young branches, leaves, buds, flower buds, fruits, absorb plant juice, plunder its nutrients, cause branches and leaves and flowers to curl, and even the whole plant withers or dies. At the same time, coal stain disease is induced, and sometimes the pest itself is the vector of the virus disease.

Such pests mainly include aphids, scale insects, whiteflies, psyllids, leafhoppers, bugs, thrips, leaf mites, etc.

3. Moth-eating pests live in concealment, have few natural enemy species, and have strong individual adaptability, which is a kind of devastating pest of garden plants. They feed on tree branches with larvae, which not only destroys the conductive tissues and causes plant death, but also forms criss-crossing insect passages in the xylem, reducing the economic value of wood. Such pests mainly include Lepidoptera, Paradoptera, Coleoptera, Giddingidae, Weevil, Hymenoptera, Isoptera termites, etc.

4. Underground pests mainly inhabit the soil, feeding on the young roots, young stems and leaf buds of just germinated seeds and seedlings, which brings great harm to seedlings, and in serious cases, it causes lack of seedlings and broken ridges. There are many kinds of such pests, mainly including mole crickets and crickets of the order Orthoptera, lepidoptera destination tigers, grubs of the order Coleoptera, needleworms, and seed flies of the order Diptera.

The identification and control of different types of pests and diseases are also different, which are specifically divided into rust, coal stain disease, anthracnose, gray mold, leaf spot disease, etc.

1. Rust.

Identification: Mainly harmful to papaya, begonia, hawthorn, apple, juniper, cypress, frangipani, canna, maran, cool-season lawn and other garden plants. The main pathogens are fungi of the order Basidiomycetes, Winter Sporodia, and Rust.

In the warm and humid spring and autumn, the disease is severe, and it becomes a parasite.

Prevention and control: spraying fluconazole (Lane Ping'an antirust) wettable powder 1000 times liquid, tebuconazole, enoximel and so on in the growing season can have a better control effect.

2. Coal pollution disease.

Identification: small black mildew spots appear on the leaves and branches, gradually expand and become sheets, and the mold layer is covered with leaves and branches, and some are black flakes and can be peeled off. Coal bacteria are spread by wind, rain and insects.

Prevention and control: During the dormant period, do a good job of cleaning the garden, and spray Baume 3-5 degrees of stone sulfur mixture. Kill overwintering germs, and in the early stage of the disease, you can spray Shi Lane Ping'an Yubao to avoid the outbreak of germs.

3. Anthrax.

Identification: Occurs on the leaves, the lesions are green or dark yellow at first slightly concave, and then gradually turn into black brown, round or amorphous, with a diameter of more than 3cm, the edge of the lesions is raised, and the small black spots that are scattered or rotated on the lesions can be combined into plaques, so that the whole leaf dies.

Prevention and control: Two weeks before the occurrence of the disease, Lane Ping'an Yushou and Lane Ping'an Imperial Guard diluted 600-800 times of the solution, sprayed the foliage, and sprayed once in 7-10.

4. Botrytis cinerea.

Identification: Mainly damage flowers and shoots, after the flower buds are infected, at first they are water-stained irregular spots, and the lesions continue to expand, and the whole bud becomes soft and rotten. Diseased buds wilt and hang on the diseased tissue, and pathogenic bacteria will also attack the branches that have been removed, and in warm and humid conditions, a large gray mold layer will be produced in the diseased area.

Prevention and control: Before the onset of the disease or in the early stage of the disease, the diseased leaves, branches, buds and diseased flower buds should be removed in time, and then the foliar spray of 600-800 times of the liquid of Lane Ping'an Yushou, each time the interval of 10 days of medication, the dosage can be increased when the disease is serious.

5. Leaf spot disease.

Identification: Plant leaf spot disease harms leaves, causing local tissue bad thoughts to die, forming lesions of different sizes, shapes and colors. Lesions include dark spots, brown spots, round spots, corner spots, wheel spots, etc. Leaf spot diseases generally occur from May to November.

Prevention and control: spray difenoconazole 2000 times + propiconazole 1500 times or fluconazole 2500 times, Ningnanmycin 2000 times, combined with potassium dihydrogen phosphate 450 times, every seven to ten days, two to three times at a time, be sure to pay attention to the dosage, do a good job of secondary dilution, and use it now.

The main types of plant diseases are discoloration, decay, deformity, necrosis, etc., these diseases are more harmful to plants, will affect the normal growth of plants, and will lead to direct death of plants.

1. Discoloration

Discoloration should be the most common among the types of plant diseases, mainly referring to the fading of plants from the initial green to yellow, and also changing to other colors, green to yellow is the most common, there are many factors in the process of plant growth will cause it to change color, generally improper maintenance may also be caused by viruses.

2. Decay

Rot mainly refers to the destruction and elimination of tissues and cells in plant roots, stems, flowers, fruits and other parts, which is a more serious type of disease, the plant with serious decay will die directly, and the plant after general decay is difficult to repair, because plant decay is often caused by fungi and bacteria, which have seriously damaged the tissues of plants.

3. Deformity

In fact, deformity in the process of plant growth is also one of the common diseases, usually roots, stems, branches, leaves, flowers, fruits and other parts are prone to deformity, it may be that the moment the seed is planted has been naturally deformed, and it may also be caused by external factors in the process of acquired growth, deformed plants will change the appearance of the plant, making it look unsightly.

4. Necrosis

This disease is local, generally due to the necrosis caused by the death of local cells and tissues of plants, and the cause of local cell and tissue death may be caused by some pests and diseases, generally necrosis is mainly manifested in the branches, leaves, fruits and rhizomes, this disease is relatively serious, and the plant will face death if it is not treated in time.

Summary. Pests, as the name suggests, are harmful insects, which are the definition of some insects by humans, as opposed to beneficial insects, which are mainly divided into insects and non-insects, and there are many types and quantities. Pests that often appear in life, such as mosquitoes, flies, fleas, cockroaches, etc.;These small organisms often have a negative impact on human life and production, and even bring death and serious disasters to plants.

Pests, as the name suggests, are harmful insects, which are the definition of some insects by humans, as opposed to beneficial insects, which are mainly divided into insects and non-insects, and there are many types and quantities. Pests that often appear in life, such as mosquitoes, flies, fleas, cockroaches, etc.;These small organisms often have a negative impact on human life and production, and even bring death and serious disasters to plants.

The above is mine, I hope it can help you, thank you ( -

Abstract 1Grasshoppers, herbivorous insects with chewing mouthparts. The tentacles are short whip-shaped, have powerful hind legs, and can use bounces to avoid predators.

The body color is green and brown, which is the protective color of the living environment. There are more than 12,000 species of grasshoppers in the world, distributed in tropical and temperate grasslands and deserts around the world.

2.Spider mites.

Red spider, also known as cotton red spider, commonly known as big spider, big dragon, sand dragon, etc., scientific name leaf mites, the species of our country are mainly cinnabar leaf mites, belonging to arachnids, ticks, leaf mites. It is widely distributed and has a miscellaneous diet, which can harm more than 110 kinds of plants.

What are the other pests? What are their shapes, habits, and hazards?

Hello, I'm glad to be able to answer for you, the system here queries these relevant information as follows1Grasshoppers, herbivorous insects with chewing mouthparts. The tentacles are short whip-shaped, have powerful hind legs, and can use bounces to avoid predators.

The body color is green and brown, which is the protective color of the living environment. There are more than 12,000 species of grasshoppers in the world, distributed in tropical and temperate grasslands and deserts around the world. 2.

Red spider red spider, also known as cotton red spider, commonly known as big spider, big dragon, sand dragon, etc., scientific name leaf mites, China's species are mainly cinnabar leaf mites, belonging to arachnids, tick mites, leaf mites. It is widely distributed and has a miscellaneous diet, which can harm more than 110 kinds of plants.

Can the teacher ask you another question?

What are the main pests in the underground part of medicinal plants?

Find out for you now.

Hello! There are many types of insect pests of medicinal plants, which can be divided into the following types according to the different parts of the pest. 1.

Underground pests. It mainly includes grubs, ground tigers, mole crickets, needleworms, etc. Underground pests are complex and rampant, and are important pests of a variety of medicinal plants, especially root medicinal plants.

The main pests and diseases of potted gerberas are leaf miners, whiteflies, thrips, aphids and Fusarium pythium. Yellow sticky insect boards can be used to detect insects, and if leaf miners are found in the greenhouse, sprays are applied every other week in winter and every 5 days in summer.

Common pests and diseases.

1. Red spiders: mainly harm leaves, branches and fruits. Pale spots appear on the front of the affected leaves and on the surface of the fruit. When there are 5-10 insects and eggs on each leaf (fruit), it is the key control period.

2. Rusty ticks: mainly harm leaves and fruits, and the fruits form hemp oranges. When there are 2-3 insects on each leaf and fruit or gray dew, it is the key control period.

3. Scale insects: mainly harm leaves, branches and fruits. The affected leaves turn yellow, causing rough and uneven branches and fruits. When each leaf (fruit) begins to exist, the larval growth stage, especially the first instar stage, is the key control period.

4. Leaf miner moth: mainly harms leaves. There are many silvery-white insect passages on the affected leaves. The germination period of summer and autumn shoots is the key prevention and control period. That is, 7-10 days after the shoots, when the leaf rate of the young shoots with insects or eggs reaches 20%, it is the control period.

5. Canker disease: mainly harms leaves, branches and fruits. The lesion is characterized by a spongy tear with a slight depression in the middle. The shooting, flowering and young fruit stages are the periods of pesticide control.

6. Anthranose: mainly harms leaves, branches and fruits. There are small black dots on the lesions. The summer and autumn shoot extraction period and the young fruit stage are the key control periods.

7. Scab disease: mainly harms leaves and fruits. The lesion is raised into a nodulous shape. The spring shoot germination stage and the young fruit stage are the key control periods.

8. At the same time, it is necessary to strengthen the prevention and control of gidding insects (including two kinds of skin explosion insects and skin slipping insects) and longhorn beetles (manual killing and poisoning with pesticides), Spodoptera exigua.

If the pesticide has been used many times or there is no effect, it may be that the pest and disease has developed resistance to the insecticide fungicide, and this solution can choose to add some synergist additives that can eliminate resistance to the insecticide fungicide, which can increase the insecticidal and sterilization ability of the liquid, and also increase the adhesion ability, so that the liquid can penetrate into the inside of the insect body. At present, there are many such synergist additives on the market, among which the organic fluorine synergist additives have good safety effects.