Tomato horn leaf yellow, a little late blight leaf mold how to whole

Tomatoes have two diseases, leaf mold and late blight, so it is necessary to carry out timely **and separation**.

Leaf mold generally starts from the lower leaves, and gradually expands to the upper leaves, the front of the leaves first appears irregular light yellow green spots, the back of the leaves initially grow a white mold layer, and then become gray-brown or black-brown mold layer, and the front of the leaves can also grow black mold in the later stage.

The temperature is 22 degrees, the humidity is greater than 90% is conducive to the occurrence of leaf mold, high temperature and high humidity is the favorable conditions for the occurrence of leaf mold, when the temperature is above 33 degrees has the effect of inhibiting the pathogen, you can consider the appropriate high temperature baking shed.

The choice of agent is recommended to use polyantimycin or pyroxazole or acridium amide or pythium or pyrimethricyclamine or azoxystrobin plus tebuconazole, or benzazoxystrobin or lunasen or chunleimycin spray should be uniform, the amount of water should be sufficient, and it is best to add foliar fertilizer to restore the damaged foliage.

Late blight, an epidemic disease under medium temperature and high humidity conditions, the infected leaves start from the leaf edge to form dark green, water-stained, large lesions that are not limited by leaf veins, and under normal circumstances, the susceptible fruits do not soften and do not rot, but become hard.

At present, the good effect is enoylmorpholine or fluoromorpholine or frost urea cyanide or silver farry or cyanogluzole or crew or anti-lump net or increase the power to win green, colleagues add mancozeb or propionate zinc or azoxystrobin, alternately used, the spray is uniform and thorough.

Remove diseased branches, leaves, and fruits in time, and take them out for burning.

Can be treated with chlorothalonil.

Chlorothalonil is a high-efficiency, low-toxicity and broad-spectrum fungicide, which is widely used to control fruit trees, vegetables and leaves, and other pests, and also has a good control effect on rice, wheat, cotton and other diseases. It is also used as an industrial antifungal agent and fruit preservative.

It has a preventive effect on a variety of fungal diseases. The efficacy is stable and the residual effect period is long. It can be used for wheat, rice, vegetables, fruit trees, peanuts, tea and other crops. For example, wheat scab should be treated with 75% wettable powder.

spray with 6kg of water; Vegetable diseases (tomato early blight, late blight, leaf mold, melon downy mildew) with 75% wettable powder 135 to 150g, spray 60 to 80kg of water; For downy mildew and powdery mildew of fruit trees, spray 30 to 40kg of water with 75% wettable powder 75 to 100g.

How to use: 1. Prevention and control of jujube, apple and other fruit tree diseases. From the initial onset of the disease, to mid-August, spray 800 to 1000 times of 56% azine bacteria chlorothalonil emulsion + 1000 times "fruit treasure" (special type for fruit trees) every 10 to 15 days, which can prevent and control a variety of fruit tree rot, downy mildew, brown spot and powdery mildew.

Be careful to alternate with other biocides.

2. To prevent and control cucumber downy mildew, powdery mildew and other diseases, you can spray 800 to 1000 times of 56% azine bacteria and chlorothalonil emulsion + 1000 times "fruit treasure" (special type for fruit trees) at the beginning of the disease, once every 7 to 10 days, and spray 2 to 3 times continuously.

3. To prevent and control the disease, downy mildew, powdery mildew and other diseases of a variety of vegetables, start spraying 800 to 1000 times of 56% azine bacteria and chlorothalonil water emulsion + 1000 times "Caibao" (special type of melon and eggplant) at the beginning of the disease, once every 7 to 10 days, and spray 2 to 3 times continuously.

4. For the prevention and control of vegetable diseases, tomato early blight, late blight and downy mildew, in the early stage of the disease, spray 800 to 1000 times of 56% azine bacterium chlorothalonil emulsion per mu, and spray once every 7 to 10 days.

It can prevent and control melon downy mildew and powdery mildew; Tomato early blight, late blight, cucumber gray mold, leaf mold, etc.

When using, be careful not to mix with alkaline pesticides such as stone sulfur. FU and DP are best used under the condition of condensation on the foliage, which is conducive to exerting medicinal effects.

Concentration: 800 to 1000 times of 56% azyl bacteria chlorothalonil emulsion, 600 times of 70% wettable powder, 400 times of 50% wettable powder; 45% smoke agent 200 to 250g mu; 5% powder 1kg mu.

Precautions. 1. Chlorothalonil is harmful to fish, and it must be kept away from ponds, lakes and streams when applying pesticides. Do not pollute the water source with the liquid used to clean the utensils.

2. This product should be moisture-proof and sun-proof, and stored in a cool and dry place. It is strictly forbidden to mix with food, seeds, and feed to prevent misingement and misuse. Disposed of discarded containers after use.

The oil agent can cause pesticide damage to peach, pear, persimmon, plum and apple young fruit.

4. It is harmful to silkworms, silkworms and bees, and it is necessary to do a good job of prevention when using it.

First, take a clear picture of the disease department to determine the disease.

Second, tomato late blight, the resistance is different in different places, it is recommended to choose one or two mixtures of enoylmorpholine, manganese zinc frost urea, downy mildew hydrochloride, methamaline manganese zinc, oxazole manganese zinc, flumorpholine manganese zinc, cyanofrostazole, fluether amide and other ingredients to choose one or two mixtures (in severe cases), alternately.

If it is a protected greenhouse, pay attention to controlling the humidity, and on rainy days, it is recommended to use chlorothalonil fogging agent to control the condition. ）

Prevention first, comprehensive prevention and control (reduce the amount of disease prevention). Use pesticide ingredients alternately, and do not use the same pesticide ingredients consecutively. This is the principle of crop protection.

Third, leaf mold disease, the resistance is not the same in various places, it is recommended to choose one or two, alternate pesticide ingredients, alternating pesticide ingredients.

It is better to spray with silicone additives. Hit it all over and through. In the case of greenhouses, humidity should be controlled, and sterilizing fogs should be used to control the condition on rainy days.

Prevention first, comprehensive prevention and control. Use pesticide ingredients alternately, and do not use the same pesticide ingredients consecutively. This is the principle of crop protection.

How to effectively control tomato late blight?

Prune and prune in time, pay attention to ventilation, light transmission, and reduce humidity. When diseased plants are found, remove diseased leaves, branches and fruits in time, and apply pesticides to surrounding plants to prevent spread. After the onset of the disease, the spray application can be used 6875g of flupyramid downy mildew (silver far) suspension 2000 times, 25% azoxystrobin (amisida) suspension 1500 times, 58% methafen manganese zinc wettable powder 500 times, 72% frost urea manganese zinc (800 times of Kelu wet powder, the use of pesticides should be rotated to slow down the emergence of drug resistance.

What are the symptoms of tomato leaf mildew?

Leaf mold mainly harms leaves, and in severe cases, it also harms stems, fruits, and flowers. The leaves are infected, the front of the first leaf appears irregular or oval yellowish green spots, the edge is not obvious, the back of the leaf produces a white mold layer, with the expansion of the disease, the leaves gradually curl from the bottom to the top, the mold layer becomes gray-brown or black-brown velvety, and the lesions on the front of the leaf can also grow black mold when the humidity is high. At the onset of the disease, the lower leaves start first, and then gradually spread upward, so that the leaves of the plant are yellow-brown and dry, and in severe cases, it can cause the whole plant leaves to curl.

Lesions similar to leaves can also be produced on young stems and fruit stalks, and can extend to flowers, causing flower and fruit drop. When the fruit is diseased, black round or irregularly shaped lesions are formed near the fruit pedicle or on the fruit surface, hardened and sunken, and cannot be eaten.

How to effectively control tomato leaf mildew?

Proper watering control, especially on rainy days and after the onset of the disease. Prune and prune in time to facilitate ventilation and light. Avoid excessive application of nitrogen fertilizer, and appropriately increase phosphorus and potassium fertilizer.

For the prevention and control of pesticides, you can choose 2000 times of 10% difenoconazole water-dispersible granules, 600 times of 10% polyantimycin wettable powder, 800 times of 70% methyl tobuzine wettable powder, 1500 times of 30% pyrimethamine suspension, 600 times of 47% Garinone wettable powder, 3500 times of 428% fluoromycete and oximestrobin suspension, 2500 times of 75% oxime and pentoxidol water-dispersible granules, 1500 times of 30% ether bacteria and acetyroyl suspension, and spray 2 3 times, 7-10 days apart.

Epidemic disease. The above two mixed preparation formulas are mainly suitable for the early stage of the disease, that is, when tomato early blight and late blight are found in the field, the effect is better, and WeChat search vegetable farmers circle attention. Of course, according to the occurrence and development law of early blight and late blight of local tomato, before these two diseases are found, a single dose of one of the above-mentioned mixed preparations can be used for protective prevention, so as to achieve the purpose of reducing the cost of medication.

Generally, when the disease is more serious, the above two mixtures must be used alternately, and the effect is the best. The main purpose of using a mixture is to prevent the development of resistance.

Refined nail cream and mancozeb are made of strong systemic and ** fungicide methalene and protective, contact fungicide mancozeb through scientific methods, which has the bactericidal characteristics of methafen and mancozeb, and expands the bactericidal spectrum of two single agents, which can delay the emergence of antimicrobial resistance of pathogens. Although methyl cream and manganese zinc are mixed preparations, long-term single application should be avoided as much as possible when used, and should be used alternately with other effective protective or first-class fungicides chlorothalonil, enoyl manganese zinc, cyanide frost urea, pyraclostrobin, etc., to avoid drug resistance.

The trade name of oxazolone cyanide is fast and fast, with the advantages of wide bactericidal spectrum, long-term prevention, and rapid development, and the agent has the characteristics of being able to penetrate deeply into the surface of the leaf, strong adhesion, long protection period, low dosage, leaf preservation and fruit protection, low toxicity, and safety for humans, crops and the environment. The control effect of tomato early blight and late blight is better. Enoylmorpholine is a morpholino fungicide, which specializes in oocyticide fungi, but it has a relatively high risk of resistance when used alone, and is often mixed with other agents.

It is necessary to pay attention to the dosage of mixed medicines, and pay attention to the vegetable farmer circle by searching on WeChat. For the above-mentioned pesticide mixture with the same object, the respective dosage should be divided by 2 when the two pesticides are mixed to prevent pesticide damage.

If you want to mix 68% methamethaline manganese zinc water dispersible granules 500 times + 25% pyraclostrobin emulsifiable concentrate 1500 times 100 kg, the dosage of the two pesticides is.

1. Symptoms 1Late blight leaf infection is mostly from the tip or edge of the leaf to appear lesions, and white mold will grow on the lesions on the back of the leaf; When the stalk is infected, there will be black and yellow lesions, and the affected parts are often sunken, which eventually leads to wilting or lodging of the plant; Fruit infection mainly occurs on green fruits, the lesions are dark green in oil at first, and then turn dark brown to tan, and the lesions are irregular

1. Symptoms.

1.Late blight leaf infection is mostly from the tip or edge of the leaf to appear lesions, and white mold will grow on the lesions on the back of the leaf; When the stalk is infected, there will be black and yellow lesions, and the affected parts are often sunken, which eventually leads to wilting or lodging of the plant; Fruit infection mainly occurs on the green fruit, the lesions are dark green in oil at first, and then turn dark brown to brown, the lesions are irregular moire, slightly concave, the edge is obvious, the fruit is generally not soft, and a small amount of white mold grows on it when the humidity is high, and it rots rapidly. In severe cases, the whole tomato plant will turn black and die.

2.Leaf mold mainly affects tomato leaves, and in severe cases, it also affects stems, flowers and fruits. Generally, it spreads upwards from the lower leaves of the diseased plant, and at first there are greenish and yellowish spots with unclear edges on the front of the leaves, and then a milky yellow gradually turns to gray-brown to black-brown velvety mold layer grows on the diseased spots on the back of the leaves.

In severe cases, it can cause whole lobe curl necrosis.

Second, prevention and control methods.

1.Agricultural control. According to the weather conditions, the humidity in the shed and the time of foliar condensation can be reduced as much as possible through reasonable ventilation, which has a certain control effect on the disease.

Prune and prune in time, remove the old leaves and yellow leaves in the lower part of the plant as much as possible, and increase ventilation. Implement formula fertilization, avoid excessive nitrogen fertilizer, and appropriately increase phosphorus and potassium fertilizer.

2.Pharmaceutical prevention and control. After the central disease strain was found in the late blight, 45% chlorothalonil fumigation agent could be used to smoke the shed per mu. Spray with 800 times of downy mildew water agent or 1000 times of flupyridine downy mildew suspension agent, spray 1 time every 7 days, spray 2 3 times.

When the disease of leaf mold disease develops, you can choose to close the shed at noon on a sunny day for about two hours of 30 33 high temperature treatment, and then ventilate and cool down in time to inhibit the development of the disease. It can be sprayed with 15% immazole fumigant, 35% fluorobacterium tebuconazole suspension, 43% flubacterium oximetrostrobin suspension or 47% Chunlei Wang copper wettable powder, sprayed once every 7 10 days, sprayed 2 3 times, pay attention to alternate medication.

Hello. If the leaves of the tomato.

It's starting to turn yellow.

If excluded is watering too little.

Causes the ground to dry up.

The leaves turn yellow.

It is necessary to consider that the tomato plant is sick.

Symptoms: Oval or irregularly shaped pale green or pale yellow pale green spots appear on the front of the leaf when the leaf is damaged, until the whole leaf is yellow. The back of the leaf forms nearly round or irregular white mold, and when the disease is severe, the mold is covered with the back of the leaf, and the color changes to gray-purple or dark green, causing the whole leaf to gradually curl from bottom to top.

The fruit is damaged, and black hard lesions are formed around the pedicle, and the pedicle is slightly concave downward. The flowers become moldy and die after being damaged. Symptoms on petioles and young stems are similar to those on leaves.

Leaf mold control methods: choose disease-resistant varieties. Such as Jiafen No. 15, Jinpeng No. 1, Zhongza No. 9, Dongnong 712, Dongnong 708, etc.

Shed disinfection. Before planting, 2 grams of sulfur powder per cubic meter of space plus 4 5 kg of sawdust, and the dark fire behind the closed shed is lit for 24 hours, and then ventilated for 24 hours, and the tomato can be planted. Ecological prevention and control.

Strengthen the management of room temperature and humidity in the shed, ventilate in a timely manner, and control watering appropriately. Pharmaceutical prevention and control. Spraying 50% iprodione 1000 times solution, or 60% carbendazim hydrochloride 600 times solution, the control effect is better.

Diseased leaves and fruits of tomato gray mold (infected) by stigma