How to prevent celery leaf spot? Pest and disease control of celery

Leaf spot disease mainly harms the leaves and affects the planting efficiency, so in the planting, crop rotation should be implemented, and the seeds should be soaked and sown, the humidity and temperature in the shed should be controlled during the growth, the diseased leaves should be removed after the onset of the disease, and the agricultural anti-120 water agent should be sprayed or the use of Tector smoke agent should be used.

Seedlings should pay attention to sunscreen, rain and high temperature, timely watering, top dressing, and remove weeds in the field. Apply plantar fertilizer, reasonable dense planting, and increase ventilation and light transmission conditions.

Plant it separately from other crops, use medicine earlier if there are signs of illness, and don't water it at noon.

Common diseases: soft rot, soft rot, virus disease, early blight, sclerotinia sclerotinia disease.

Soft rot: This disease usually occurs during the transplantation of celery when it is young, or during the growth period after transplantation. When the disease is severe, it causes celery to rot and emit a pungent foul smell.

Heart rot: This disease can overwinter in the soil, and will spread with the soil to the plants the next time it is planted. It is easy to cause this disease when the temperature reaches more than 36 degrees Celsius and below 12 degrees Celsius.

The best temperature for celery is between 27 degrees and 30 degrees. At the same time, germs can also be transmitted through watering, insects, etc.

Viral disease: This disease mainly erodes the leaves of celery. Originally it also occurred first by the leaves of celery. This disease is mainly caused by too high and too low temperatures. Between 20 and 25 degrees, combined with the rain and humidity of the air, it is easy to trigger the disease.

Early blight: It is the same disease as spotted disease. It can occur both at the seedling stage and after adulthood. The main cause of this disease is also due to excessive temperature and humidity.

Sclerotinia sclerotinia disease: Celery can get sick throughout the growing season, and the main cause of this disease is also caused by excessive temperature and humidity.

Prevention and control methods: 1Try to choose varieties with strong disease resistance before planting.

2.Before sowing, soak the seeds in warm water at 48 degrees for about half an hour, which can effectively prevent and control the diseases brought by the seeds before sowing.

3. Reasonable fertilization, and timely removal of diseased bodies to prevent spread. Pay attention to the circulation of air and avoid moisture.

4 Can be prevented with drug sprays and**.

Common insect pests: aphids, spotted divers, vegetable moths, jumping beetles, etc. Control measures: imidacloprid, aphid mite, spotted latent and other drug sprays can be used to kill.

What to do about celery leaf spot, celery leaf spot control methods.

Celery leaf spot symptoms:

Celery leaf spot, also known as early blight and spot disease, is one of the common diseases of celery. Celery leaf spot occurs mainly on leaves, and old leaves are more susceptible than new leaves. Leaf spot disease lesions are yellow-green water soaked at first, and later develop into round and irregular shapes, and when the disease is severe, the lesions are connected into patches, and the leaves die.

When the air is humid, the lesions are densely covered with gray velvety mold. The lesions on the stem and petiole are oval, 3-7 mm in diameter, gray-brown, slightly concave, the whole plant is inverted when the disease is severe, and a gray mold layer grows on the surface of the diseased part when the disease is high.

Celery leaf spot control methods:

1. Select disease-resistant varieties Choose disease-resistant varieties according to production practice.

2. Seed disinfection. Soak the seeds in 50 degrees warm water for 30 minutes, dry them and sow them, or soak them in 50% Fumei double wettable powder 600 times for 50 minutes, and then rinse them with water or dry them to sow directly.

3. Seedlings should be shaded in the high temperature season, prevent heavy rain, and cultivate strong seedlings.

4. Implement crop rotation for more than two years.

5. Reasonable dense planting, time seedlings, hoeing, pay attention to ventilation and light transmission, reduce the humidity in the field, and strictly prohibit flood irrigation; Apply more organic fertilizer, timely top dressing, you can use "fertile leaf ** water-soluble fertilizer", watering, to promote the healthy growth of plants, enhance plant disease resistance.

6. Immediately after harvesting, remove the sick and remnants, and burn them or bury them deeply.

7. Pharmaceutical prevention and control. In the early stage of the disease, you can choose 50 carbendazim wettable powder 600 times, or 50 methyl tobuzin wettable powder 600 times, or 70 mancozeb wettable powder 500 times, or 75 chlorothalonil wettable powder 600 times, or 12 green milk copper emulsifiable concentrate 400 times, spray once in about 7 days-10 days, 2 times to 3 times in a row.

(1) Leafy vegetables often appear in various shapes and colors of spots (black spots, brown spots, white spots) on the leaves of leafy vegetables, which are collectively referred to as leaf spot disease by vegetable farmers. Common ones are lettuce black spot and brown spot, cabbage white spot, celery leaf spot (bacterial and fungal, here refers to fungal).

2) The main symptoms of damage are the leaves, which appear yellow-green water-stained spots on the leaves at first, and then develop into round or irregular gray-brown lesions, and in severe cases, the lesions expand into plaques, and eventually cause the leaves to die. The lesions on the stem or petiole are oval, grayish-brown, slightly concave, and the whole plant is lodging in severe disease. When the humidity is high, the diseased parts grow gray-white mold layer.

3) The pathogen is a kind of cercospor, which belongs to the subphylum Semi-Know, which overwinters on seeds or diseased residues with mycelium, spreads by rain, air currents, and farming, and invades by stomata or epidermis. High temperature, rainy or high temperature and drought have a long duration of dew condensation at night, and they are prone to disease, especially lack of water, lack of fertilizer, excessive irrigation or poor plant growth. (4) Prevention and control methods: select disease-resistant seeds and carry out seed disinfection, strengthen field management, and spray in the early stage of disease

Shilik 1000 1500 times liquid, R&F 800 1200 times liquid, Keneng 600 800 times liquid, 75% chlorothalonil 600 800 times liquid, 800 1200 times chlormonium 1200 times liquid, Shilik 1500 2000 times liquid.

Bacterial leaf spot is an important disease of celery cultivated in protected areas, with a general incidence rate of 5% to 20%, and more than 80% of the diseased plants when it occurs severely, which has a serious impact on yield and quality.

Bacterial leaf spot disease mainly affects leaves, and can occur from seedling stage to harvest stage. At the beginning of the disease, light brown and water-stained irregular spots are produced on the leaves, which gradually develop into polygonal shapes due to the restriction of leaf veins when expanding, and in severe cases, several lesions on the leaves are connected and fused into large lesions. Sometimes the lesions develop along the leaf veins, the leaf veins turn brown and twist and deform, and the later lesions gradually turn brown and the leaves die.

Prevention method: Ecological control method should be used for celery cultivated in greenhouses, and timely ventilation and dampness should be released to reduce foliar condensation. Before the onset of the disease or when there is a single diseased strain, the commonly used agents are gentamicin 2000 times, or haloperic acid 600 times, or noromycin 2000 times, or 56% of the mountain water dispersed microparticle 600 800 times, or 77% can kill wettable powder 500 times, or 30% copper hydroxide suspension 800 times of liquid respectively, respectively, mixed with 600 times of Tianda 2116 + 3000 times silicone + 1% fermented milk alternate spray, every 7 10 days 1 time, continuous spraying 2 3 times.

Hello? FYI: Today I.

From planting to slow seedlings to small water watering, because the air is relatively dry, hot, in order to prevent celery leaf blight, spot blight, can be used Biluqing 25g, aphid lice speed gram 15g, add 30 kg of water, slow seedlings to carry out seedlings, seedlings are generally not watered, control the amount of water is generally 10-15 days, if black spot or sclerotinia is easy to occur during this period, with 50 of promethine 20g 5g of mycolecin, the period of vegetative growth is relatively vigorous, that is, after the temperature drops to 20 degrees, cabbage enters the growth period, 40 degrees below the growth of celery into the peak period, generally 50-60 days, to fertilizer water storm, Hui Manfeng flush release fertilizer 20-30 kg, at this time celery white roots have been covered with the surface, indispensable water, after the frost falls, appropriate water, or not watering, is conducive to the growth of the petiole, when the celery grows to 20-30cm when soft rot is more prevalent, with pictomycin or occtromycin 5g day up to 2116 leafy vegetable type 25g, add 30 kg of water, virus disease can be killed quickly 15ml 2116 leafy vegetables 25g, Add 30 pounds of water, spray 1 time every 15 days, use Shennongdan when cultivating the root knot nematode, and use 4-5 pounds per acre.

Celery leaf spot begins to occur at the celery seedling stage, and the growing plants are severely damaged. Mainly harms leaves. First, starting from the leaf margin, the leaf spots become pale green and overflowing.

The spots start small and gradually enlarge in the later stages. The spots are light brown in the middle and raised in the middle, with a yellow halo around them, and the spots can extend to the whole leaf. Eventually the entire leaf dies and the spots become translucent.

Damage to the stem, at the beginning there is a small class of water immersion round, and the lesions at the back are depressed. The condition was severe, the celery fell to the ground, and the white mold layered. The pathogen is caused by Cercospora subphylum Cercospora and overwinters mainly by invading the seed coat, hyphae and spores in the remnant plant and soil with hyphae attached to the seed surface.

In the second year, under suitable temperature and humidity conditions, new conidia are produced, which are spread to plants through rain, farming tools or tillage operations, and invade directly from the stomata or epidermis to cause diseases. The disease belongs to the high temperature and high humidity type, which is relatively common and prone to outbreaks.

Before planting celery, the soil should be dug deep and dried in the sun to effectively kill germs and underground pests in the soil. For formal planting, 40-50 kg of quicklime is used per acre, mixed well with soil and fertilizer, and then sprayed and sterilized. First of all, it is necessary to plant reasonably and densely, and it is recommended to use wide ridge planting method to facilitate drainage and irrigation.

During the planting process, it must be watered reasonably, and flood irrigation is strictly prohibited. Once a disease occurs, watering should be reduced or suspended to prevent excessive humidity in the field. After the outbreak of the disease, we should try our best to control the amount of watering.

The pathogenic bacteria overwinter with hyphae attached to the surface of the seeds to invade the seed coat, residual diseased plants, and hyphae and spores in the soil.

Under suitable environmental conditions, the hyphae produce conidia, which are transmitted to the host plant by air currents, and in the presence of water droplets, invade directly from the host epidermis, causing primary infection. Sowing diseased seeds, after the emergence of seedlings, will be infected with the disease, in the disease site will produce a new generation of conidia, through wind and rain, multiple re-infection, continue until the end of autumn, the damage will gradually increase. The pathogenic bacteria prefer high temperature and high humidity environment, the optimal temperature for the onset of disease is 22 30, the relative humidity is 85% 95%, the optimal temperature for conidia formation is 15 25, and the optimal temperature for germination is 28.

The ideal temperature range for conidia germination is 15 20 °C, which requires less humidity and is more conducive to the onset of disease. Low-lying areas are prone to disease, but they are also prone to disease in conditions of high temperatures, droughts, and nighttime dew. In addition, insufficient fertilizers, poor drainage, over-irrigation, or weak plants are also severe.

It will cause a decrease in the yield of celery, and there will also be some problems with spot diseases, which are very bad behaviors and should be stopped.

Celery bacterial leaf spot is an important disease of celery, both in protected and open fields, with an incidence of 80% in severe cases, affecting the yield and quality of celery, mainly harming leaves, and the pathogen of celery bacterial leaf spot disease can overwinter on weeds and other crops, becoming the source of primary infection, and the growth temperature is suitable for 30, 41 and does not grow.

It is mainly harmful to leaves, and old leaves are more susceptible to disease than new leaves. Leaf damage, first at the leaf edge, petiole disease, gradually spread to the whole leaf, the leaf damage in the early stage of yellow-green water-soaked spots, later development into round or irregular shape.