Tomato diseases, ask for advice, common diseases of tomatoes

The best method of tomato rot disease:

Soft rot is a bacterial disease that mainly infects stems and fruits. The stem mostly starts from the pruning wound, then extends inward, and finally the pith rots, has a foul odor, and after losing water, the diseased stem is hollow. The vascular bundles of the diseased stem are intact and not infected.

When the fruit is diseased, the peel is complete and bright, the flesh rots and becomes soft, and after breaking, it emits a foul odor, which is easy to fall off, and becomes a white zombie fruit after drying.

Prevention and control methods of rot disease:

1. 1500-2000 times of agricultural streptomycin sulfate soluble powder is evenly sprayed, and the control effect is generally about 60%.

2. Spray evenly with Bacillus subtilis + Jinggangmycin 800-1000 times, and the control effect is about 70%.

3. Multi-viscosity Bacillus + Julixing 481 mixed with water, 1000-1200 times liquid evenly sprayed, the control effect is more than 90%, and the number of spraying depends on the condition.

Tomato cotton rot, tomato late blight mixed infection, excessive humidity, poor ventilation and other factors, 58% methalene-zinc, 70% manganese-zinc can be used. Ethyl aluminum, 64% manganese-zinc, 69% manganese-zinc. Enoyl, 60% fluorine.

Manganese-zinc, 72% frost urea. Manganese zinc, plus chunleimycin for prevention and control, the above agents are used alternately, and the prevention and control is once every 5 to 7 days.

Because of the medium and late maturing varieties, they have a long growth period, strong regeneration ability, strong branching ability, high branch formation rate, and long extracted branches, so they are suitable for topping. Combined with the selection and harvesting of the first to third spikes, the old leaves, diseased leaves, diseased branches and diseased new leaves were removed from the base.

When the diseased new shoots are 25 cm long, they are removed from the base, and the new shoots are left, and this is repeated 2 or 3 times until the new shoots grow normally and are left as the fruiting mother branches. When dealing with diseased new shoots, it is found that the branches are small and show pathological symptoms, do not rush to knock them off, and treat them after they grow to a certain extent, and at the same time remove the mouth and spray the new high-fat film to inhibit the invasion of pathogens and restore plant growth.

Prune the diseased branches, spray the tree protector after picking the leaves, and focus on spraying new shoots and new leaves. It can play a role in disinfection and sterilization.

1. Scab disease: It occurs in the green fruit stage, and water-soaked green spots appear on the fruit surface, and brown lesions appear in the later stage. 2. Tendon rot:

The color of the peel is uneven, and more organic fertilizer should be applied during the breeding process. 3. Spot blight: caused by fungi, splashed on the leaves of plants by rainwater.

4. Black spot disease: Lesions appear on the fruit surface, and black-brown mold grows.

1. Scab disease

Tomato scab disease is serious, generally occurs in the green fruit stage, there will be water-soaked green spots on the fruit surface, gradually spread outward, brown lesions will appear in the later stage, the bad fruit should be cut off in the early stage of tomato disease, and sprayed with copper hydroxide agent.

2. Tendon rot:

After the occurrence of tendon rot of tomatoes, the color of the peel is uneven, the inside is black and hard, there are green and red, in the process of breeding tomatoes, it is necessary to apply more rotten organic fertilizer, improve soil conditions, pay attention to apply less nitrogen fertilizer, otherwise the tomato will rot.

3. Spot blight

After the tomato is infected with spot blight, there will be a lot of brown round spots on the fruit, the edge of the leaf is dark brown, the disease is caused by the fungus, the rain splashes on the leaves of the plant, the leaves close to the ground are the first to disease, the yellow leaves can be cut off, and then the tomatoes are sprayed with chlorothalonil.

4. Black spot disease

Tomato black spot disease mainly occurs in the fruit that is about to ripen, there will be round or oval lesions on the fruit surface, and black-brown mold will appear when the humidity is too high, and it generally occurs in the high temperature and rainy season, and can be sprayed with chlorothalonil and difenoconazole.

The main diseases of tomatoes are: virus disease, stem base rot, gray mold, leaf mold, etc., as well as fruit burn caused by strong light, bud blight caused by high temperature obstacles, dry leaf edges, fruit cracking, etc. In addition to doing a good job in cultivation management, the following methods can be adopted for pesticide prevention and control.

Viral diseases are mainly mosaic symptoms and stripe symptoms, mosaic virus fibrous socks disease is noisy: leaf shriveling, yellow-green alternation: leaf virus disease, leaf slenderness, leaf vein deformation, linear; Leaf curl virus disease:

Twisted leaves, bent inward, streaked virus disease: green skin appears on the surface of the fruit, gradually forming rust color, not red, cut the fruit with a knife, brown streaks, high temperature and drought, insufficient nutrients, soil compaction and other favorable viral diseases. Prevention and control methods:

Spray 30-45 kg of water with 3-4 grams of 70% water dispersible granules per mu to prevent and control aphids and other stinging and sucking mouthparts pests, so as to cut off the way for insects to spread viruses and achieve the purpose of preventing and controlling viral diseases.

1. Late blight.

Symptoms: Tomato seedlings are infected, and dark green water-stained lesions appear on the leaves, which will expand to the petioles, causing the petioles to become thinner, and the color to brown necrosis, causing the seedlings to wilt and die.

Prevention and control: Tomatoes should be cultivated in ditching and ridges, planted reasonably and densely, found diseased plants in time, and sprayed with oxystrobin suspension and copper hydroxide wettable powder in time for pesticide control.

2. Brevear.

Symptoms: Bacterial wilt is a bacterial disease, which can infect bacteria at the seedling stage, but the symptoms of disease can not be seen until the early stage of fruit set, and the top, lower and middle leaves of the diseased plant will wilt one after another, and will return to normal in the evening, after which the plant will die.

Prevention and control: Promote the planting of high furrows, ensure the convenience of drainage and irrigation, and apply more decomposed organic fertilizer during the growth period to improve the disease resistance of plants. In the early stage of the disease, water thiazobium copper suspension, etc., and use Bacillus subtilis wettable powder for root irrigation before the onset of the disease.

3. Blight.

Symptoms: Blight can occur at the seedling stage, the stem base of the sick seedling turns brown, the stem and leaves will wilt and droop and dry up, and the seedling will gradually die after a week of disease spots.

Prevention and control: strengthen seedbed management, spray brassinolide water agent at the seedling stage, and spray thiophanate-methyl suspension agent or chlormethalin water agent at the early stage of the disease.

1. Tomato umbilical rot.

Umbilical rot is more common in the process of tomato planting, and is generally considered to be water abnormality, and the lack of calcium and boron caused by rot around the umbilicus.

To prevent tomato navel rot, mainly by spraying foliar fertilizer at the young fruit stage. 1% superphosphate and boron fertilizer can be used, sprayed once every two weeks or so, and sprayed 2-3 times in a row, which can have a good preventive effect; Tomato foliar calcium supplementation, can be used from the seedling stage to before harvest, generally every 10-15 days spraying, the effect is good.

2. Tomato deformed fruit.

When tomatoes are deformed, the quality of the fruit will be reduced or the value of the fruit will be completely lost, which is very harmful. If the temperature is not properly managed or hormones are used inappropriately, the fruit is deformed or cracked. In order to promote fruit expansion, some growers use bulking agents to make tomatoes appear hollow.

In order to prevent tomatoes from deforming fruits, we should correctly use the bulking agent should grasp the timing, and use it under the conditions of good plant growth, sufficient light, suitable temperature, and sufficient water and fertilizer in the field, so as to greatly reduce the probability of hollow fruits.

3. Tomato green peel fruit.

Tomato green peel fruit is the surface of the fruit local browning or green skin, some fruits are brown brown, hard, necrotic, flesh hardening, poor quality, no taste to eat. The reasons for the occurrence of green peel fruit include insufficient light, high temperature and humidity, partial application of nitrogen fertilizer in the field, and excessive water accumulation.

In order to prevent green peel fruit, we can choose medium-shaped fruit varieties with thin skin, small leaves, and resistance to green peel fruit. Reapply organic fertilizer in the field, increase light supplementation equipment on rainy days, regularly spray potassium dihydrogen phosphate on plants, or special foliar fertilizer, and strengthen water and fertilizer management.

4. Tomatoes are deficient in potassium.

The lack of potassium in tomatoes caused the leaf margins of the lower leaves of the plant to lose green and yellow, which reduced the fruit quality and caused the tomato green peel fruit. Tomatoes are deficient in magnesium, the lower leaves of the plant are generally yellowed, and photosynthesis is weakened, which seriously affects the accumulation of nutrients.

We need to carry out top dressing in the later stage, mainly phosphorus and potassium fertilizer, which can be used with fast-acting fertilizer or plant ash, and the foliar magnesium element can be sprayed with about magnesium sulfate. For other trace elements, such as boron, calcium, zinc, etc., they should also be supplemented regularly, and the dosage and concentration should be paid attention to when spraying to avoid fertilizer damage.

5. Tomato tendon rot.

Manifestations: There are two types: white and browning, the former has hard skin, pulp chaff, and slightly yellow coloration; The latter has uneven fruit surface, local browning, poor coloration of the diseased part, and often cavities.

Countermeasures: select varieties with strong resistance to viral diseases, and do a good job in the prevention and control of viral diseases; Avoid poor soil aeration, low sunlight, more nitrogen and less potassium fertilizer; Keep the soil nutrients** complete and sufficient, and avoid too much water.

Tomato diseases include virus diseases and fruit cracking, etc., and the specific control methods are as follows:

1. Viral diseases.

The seedling stage is the key period for aphid treatment and disease prevention, and the small arch shed should be arranged with a fine-eyed insect net to cultivate strong seedlings; Greenhouse for growing tomatoes, insect-proof nets and other physical prevention and control facilities are arranged in advance. Regular spraying of natural pyrethrin to control aphids and other poisonous pests; In the event of a viral disease, the use of copper salts, mushroom proteoglycans and other passivation viruses at the same time of pest control to prevent the disease from further spreading.

2. Cracked fruit. Radial cracks, with the fruit pedicle as the center to the shoulder of the fruit, radial cracking, generally begin at the green ripening stage of the fruit, slight cracks, after the color change the crack is significantly deepened and widened, sometimes reaching a very serious deep crack.

Concentric circle cracks, centered on the fruit pedicle, occur concentric intermittent microcracks on the nearby fruit surface, and are ring-shaped cracks when heavy, and mostly appear when the fruit is about to ripen.

Introduction to the cultivation method of tomatoes:

1. Soil requirements.

Tomatoes do not have particularly high requirements for the soil, and have a certain degree of fertility, which can be kept moist and loose. Tomatoes are moisture-loving fruits and vegetables, and they are not tolerant to waterlogging, so it is necessary to pay attention to drainage in the rainy season, so drainage channels should be built in planting fields.

2. Seed treatment.

Soak the tomato seeds in water for 1 2 hours, then put the seeds in warm water at 20-60 degrees Celsius, stirring constantly. Keep the seed slippery morning stare in warm water for about 15 minutes. Then continue to soak for about 5 hours to sow seeds, and most of the seeds can be sown after they are white.

In addition, in order to prevent pests and diseases at the seedling stage of tomatoes, the seeds can be soaked with 10 times trisodium phosphate or 1000 times potassium permanganate for about 15 20 minutes.

Tomato cataplexy disease: A common disease in the seedling stage of tomatoes. During the seedling raising period, the disease is severe in the low temperature and rainy years, and the severe disease often causes the seedlings to die in patches. Symptoms: Seedlings are damaged after they emerge and are infected on the stems near the ground.

It begins with dark green water-stained lesions, then turns yellowish-brown and shrivels and shrinks, and the plant is lodging, but the stems and leaves are still green.

When the humidity is high, white cotton wool mold can be seen in the diseased area and on the ground. At first, only a few plants became diseased, but it spread rapidly, and after a few days, it spread to neighboring seedlings, causing lodging in patches.

Pharmacy prevention and control bed soil treatment. Conventional seedlings can be mixed with methyl frost + carbendazim, and a variety of other diseases can also be treated. Seed treatment.

The seeds are disinfected by soaking seeds in warm soup or soaking with chemicals, and germination is promoted after soaking. Choice of agent. After the tomato seedlings are found to wilt and lodging in the seedbed, the diseased plants should be uprooted in time and in time.

You can choose Jiyu green protection or enoyl manganese zinc, downy mildew + Dysenlian, frost urea manganese zinc, oxamine and other agents. Tomato blight is one of the common diseases of tomato seedlings, which can be caused by freshly unearthed seedlings and large seedlings.

Symptom: The stem base of the diseased seedling turns brown, the diseased part shrinks and becomes thinner, and the stems and leaves wilt and die. Slightly larger seedlings wilt during the day and recover at night, and when the lesions wrap around the stem, the seedlings gradually die, but do not fall. At the beginning of the disease, oval dark brown spots appeared, with concentric ring stripes and light brown arachnoid mold.

Disinfection of bed soil with pesticides: The seedbed was sprinkled with methanesulfate and mancozeb soil to disinfect the seedbed. Pharmaceutical selection: Jiyu Green Protection 500 times liquid, chlorothalonil, mancozeb, Bacillus subtilis, etc.

Tomato virus disease is generally mild in the early stage of spring greenhouse tomato, and after entering May, fern leaves and mosaic leaves begin to worsen. After the autumn delay, the tomato virus disease was more serious than that of the spring greenhouse, and the main viruses were fern leaves and striped spots.

There are three main types of symptomatic tomato virus disease. Mosaic type. The leaves appear yellow-green or dark and shallow mottled, the leaf veins are transparent, the leaves are slightly shrunken, the diseased plants are slightly shorter, the new leaves are small, the fruit is small, the fruit surface is of poor quality, and most of them are flower-faced.