What is a bacterial disease? How to prevent it?

It refers to plants, because of bacterial infection, resulting in various soft rot, canker, bacterial wilt, and so on. The method of control is to choose varieties with high resistance to diseases and insects to plant, and then spray pesticides to control the amount of water and temperature.

Bacterial diseases are diseases that occur because of infection with bacteria. The method of prevention and control needs to spray pesticides in a timely manner, and at the same time, it should also ensure that the light is sufficient, ensure the fertility of the soil, and remove pests regularly.

Many agricultural material stores have relatively good products to find, or it is difficult to find some manufacturers on the Internet.

It is difficult to distinguish between fungal diseases and bacterial diseases, and they both have similar symptoms such as necrosis, decay, wilting, and deformity. Distinction can only be made by the different symptoms of the diseased parts of the affected crops. Fungal diseases can be seen in the affected crop disease department can see obvious mildew, powder, granular matter and other symptoms, the symptoms are actually the morphological structure of the fungal fruiting body, which is an important marker to distinguish fungal diseases. When the humidity is high, bacterial diseases can appear yellow or white droplet pus of different sizes in the diseased part, which is a unique symptom of bacterial diseases, and is a water bead-shaped, irregular granular or shiny film after drying.

Due to the limitation of the onset period and conditions, if the symptoms are not obvious, the occurrence of diseases in the field can be continued to be observed, and at the same time, the disease samples can be collected back to the laboratory, rinsed with water and moisturized to make the symptoms fully manifested, and then identified. For some diseases with special symptoms, such as bacterial wilt caused by bacteria, anatomical examination can be carried out to observe whether the diseased plant tissue has special pathological manifestations, such as vascular discoloration for diagnosis.

1. Fungal diseases:

1. Disease symptoms:

The main symptoms are necrosis, decay and atrophy, and a few deformities. The plant generally produces a white powder layer, a black powder layer, a downy mildew layer, a rust spore pile, a sclerotia, a mold, a mushroom-like matter, a cotton wool-like matter, a granular matter, a rope-like matter, a clayey granule and a small black spot, and the large symptoms can be directly observed with the naked eye.

2. Common diseases:

Smut, powdery mildew, rust, downy mildew, sclerotinia and so on. Common vegetables include eggplant verticillium, melon powdery mildew, and downy mildew; Field crops such as sunflower sclerotinia sclerotinia disease, watermelon, rice three major diseases, etc.

3. Chemical control methods:

There are many kinds of fungal diseases, and there are hundreds of conventional drugs, such as carbendazim, chlorothalonil, methyl tobuzin, amicida, etc.

2. Bacterial diseases.

1. Disease symptoms:

Bacteria invade through the stomata and wounds of the plant, and the initial lesions are water-stained or oil-stained edges, translucent, and the bacteria pus overflows on the lesions, and the plants after the onset of the disease generally show necrosis, decay or wilting. Spots, decay, necrosis, wilting, and tumors are mostly bacterial diseases.

2. Common diseases: cruciferous soft rot, Solanaceae bacterial wilt, potato ring rot, rice leaf blight, apricot leaf scorch, peach young fruit disease, bacterial perforation, etc.

3. Chemical control agents:

1) Antibiotics: agricultural streptomycin sulfate, chunleimycin, and mesomycin;

2) Copper preparations: copper hydroxide, copper king, copper alkaline sulfate, copper thiazole.

3) Others: chloroisocyanauric acid, sodium disulfonate, etc.

The common pathologies of crop diseases can be grouped into five categories, namely discoloration, necrosis, wilting, rotting and deformity.

1) After the disease, the discolored crop loses its normal green color locally or in the whole plant. If chlorophyll is inhibited or destroyed, greening and yellowing will occur; Anthocyanins are overformed, and the leaves turn red or purple-red, showing red leaves; Some of the leaves are yellow and green, showing flowers and leaves.

2) The cells, tissues or organs of necrotic crops are destroyed and die. The most common type of necrosis after the onset of crops is lesions. Disease spots can occur in multiple parts of crops, such as roots, stems, and fruits.

There are brown spots, black spots, gray spots, white spots, purple spots, etc., and there are more brown spots. The shapes are round, oval, fusiformal, polygonal and irregular.

3) The tissue cells of rotten crop diseases are destroyed and dissolved, and water flows out and decays. Such as root rot, stem rot, fruit rot and ear rot.

4) All or part of the branches and leaves of wilted crops are in a state of water loss and wither and droop. It can be divided into physiological wilting and pathological wilting. Physiological wilting is due to the lack of water in the soil or excessive transpiration at high temperature, so that the plant leaves, top tender stems lose swelling pressure and show atrophy, if the water supply in time, the plant can return to normal; Pathological wilting refers to the vascular tissue of the root or stem of the plant being invaded by pathogens, and a large number of bacteria blocking the ducts or producing toxins, hindering and affecting water transport, causing leaf wilting and yellowing, resulting in verticilla wilt, wilting, or the rapid wilting of plants and the leaves are still green is called wilt, which is mostly unable to recover, and even leads to plant death.

5) Abnormal morphology caused by stunted crop disease tissue or cell growth or excessive proliferation. The common ones are: the internodes of the whole plant are shortened, the tillering increases, and the diseased plants are shorter than the healthy plants, which is called dwarfing, such as rice common dwarf disease; Crop diseased plants grow particularly slender than healthy plants, which is called longevity, such as rice seedling disease; The development of local disease histiocytes is unbalanced, which is common in uneven foliar surfaces, called shrinkage; Crop roots, stems, or leaves that form protruding growths, called warts, such as corn warts powdery mildew.

Those who only know how to treat viral diseases, bacterial diseases and fungi can buy medicines in agricultural stores.

There are 7 kinds of bacterial diseases on crops: bacterial spot disease, bacterial perforation disease, bacterial horn spot, bacterial stem base rot, bacterial streak disease, bacterial blight disease and bacterial streak disease.

There are five main subphyla of fungal diseases.

1: Subphylum Flagellates.

Cotton mold, Pythium, Phytophthora, downy mold.

2: Zygomycetes.

Most of them are saprophytic, and only a few cause crop diseases. For example, rhizopus causes soft rot of sweet potato.

3. Ascomycetes subphylum.

Powdery mildew (powdery mildew), coccus (sweet potato black spot, cereal scab, ergot disease), sclerotinia (sclerotinia

4. Subphylum Basidiomycetes.

Black powdery mildew, rust fungus.

5. Semi-Knowing Subphylum.

Bush Sycopterium (Oryzae oryzae, Semibacterium maize, etc.), Platobacterium (Anthracnose, etc.), Coccidiospora (Brown Spot Bacterium spp., Sesame stem Blight Blight, etc.), Baccospora (Bacillus spp., etc.), Bacillus spora (Bacillus spp., etc.).

Fungal diseases must have the following two characteristics: there must be lesions present in various parts of the plant. The lesion shape can be round, oval, polygonal, whorl-shaped, or amorphous.

There must be mold or powder of different colors on the lesions, such as white, black, red, gray, brown, etc.

Bacterial diseases are mainly characterized by the following four aspects: leaf lesions without mold or powder. Decay produces mucus and emits a foul smell.

Foul odor is an important feature of bacterial diseases, and the fruit is ulcerated or scabbed, and there are small protrusions on the fruit surface. The roots are wilted, and the vascular bundles at the tips of the roots turn brown. (Note: There are some exceptions).

Farmers are the hardest and hardest. There are still pests and diseases when planting crops, and if you can't identify the types of diseases, maybe the crops will not have a good harvest! And lose money!

Diseases are broadly divided into three categories: fungi, bacteria, and viruses. So how do you identify these diseases? It's to burn diseased leaves with a lighter!

1. Bacterial diseases.

Bacterial diseases are diseases caused by bacterial infection, such as soft rot, canker, bacterial wilt, etc. The bacteria that invade plants are rod-shaped bacteria, most of which have one to several flagella, which can invade through natural orifices (stomata, skin pores, water holes, etc.) and wounds, spread by running water, rainwater, insects, etc., and spend the winter in diseased residues, seeds, and soil, and are prone to disease under high temperature and high temperature conditions.

Bacterial diseases are characterized by smelling! The rotten fungus smells thick and smelly! The odor emitted by burning diseased leaves with a lighter is a unique characteristic of bacterial diseases.

2. Viral diseases.

Diseases caused by parasitism of plant viruses. Plant viruses must live parasitically in the host cell, and they are highly specific, and a certain virus can only infect one or some plants. But there are also a few that are widely harmful; Such as tobacco mosaic virus and cucumber mosaic virus.

In general, plant viruses are only active in the living host; Only a few plant viruses can remain active in the remains of diseased plants for days, months, or even years, and a few plant viruses can survive or multiply in living insects. Plant viruses replicate nucleic acids (RNA or DNA) and protein coats in host cells to form new virions. Plant virions or viral nucleic acids are very slow to transfer between plant cells, while in vascular bundles, they can be rapidly transferred with the direction of nutrient flow of plants, causing diseases around plants.

The diseased leaves of the burning virus disease taste the same as the burnt feathers. Because the virus is composed of nucleic acids and white matter, the burning of the diseased leaves of the plant infected by the virus disease is equivalent to burning the protein, so there will be a smell of burnt feathers, which is characteristic of the virus disease.

3. Fungal diseases.

Fungal hazards, also known as fungal diseases, are infectious diseases of plants, which can infect each other, have an infection process, and the pathogens are generally parasitic fungi. There are many kinds of fungal diseases, accounting for more than 70% of all plant diseases, fungal diseases are widely distributed in China, not only in the field, but also because of its latent infection characteristics, harm the fruit, can reduce the yield, the fruit loses its commodity value, the loss is great, and seriously affects the production safety of the fruit industry.

The diseased leaves of the burning disease emit a sour smell, which is a fungal disease, and most of the fungi are mycelium composed of slender tubular hyphae, and the burning branches are good to serve and emit a sour smell. This is characteristic of fungal diseases.