What are the causes of white carrot leaves? What are your tips for preventing it?

Whitish leaves are powdery mildew, which is a disease that occurs in carrots caused by the powdery mildew fungus. It mainly harms leaves and petioles. At the beginning of the disease, white to grayish-white powdery spots are produced on the back of the leaf or petioles, and then develop into a white powdery mold layer on the leaf surface and petioles, forming many small black spots.

When the disease is severe, the leaves of the plant turn yellow and wither from bottom to top.

Prevention and control methods: Seed disinfection with 50 warm water soaked for 15 minutes, or 15% powder rust rather wet powder dressing before sowing. Agricultural measures should be reasonable and dense, avoid excessive application of nitrogen fertilizer, and increase the application of phosphorus and potassium fertilizer.

Prevent growth. Pay attention to ventilation and light transmission, and reduce air humidity.

In the early stage of drug prevention and control, 15% powdery rust rather wettable powder 1500 2000 times solution, or 20% powdery rust Ning emulsifiable concentrate 2500 times solution, or 50% carbendazim wettable powder 500 times solution, or 70% methyl tobuzin.

80 times the wettable powder, or 500 times the 40% polysulfur suspension. Spray 1 time every 7 10 days, spray 2 3 times in a row.

This symptom is that the carrot is infected with powdery mildew, and if it is not handled properly, the powdery mildew will become more and more, which will seriously affect the photosynthesis of the carrot. The methods of prevention and control are:1

Seeds are sterilized, soaked in 50 warm water for 15 minutes, or mixed with 15% powder rather wet powder before sowing. 2.Reasonable dense planting, do not overapply nitrogen fertilizer, increase phosphorus and potassium fertilizer.

Pay attention to ventilation and light transmission, and reduce air humidity. 3.In the early stage of drug prevention and control, 15% powder rust can be used, and 1500 2000 times of wet powder can be used.

Spray 1 time every 7 10 days, spray 2 3 times in a row.

This symptom is that the carrot is infected with powdery mildew, which can seriously affect the photosynthesis of the carrot. The control method is to soak the seeds in 50 warm water for 15 minutes before planting, or mix the seeds with 15% powder and rust rather wet powder before sowing.

It may be because of some pests and diseases, and it may be because there is too much water shortage, and the carrots are too dry, so we should spray it to prevent pests and diseases.

Hello, one way is to prepare in advance, that is, before planting radish, soak radish seeds in warm water at about 50 °, half an hour, you can also mix and stir with 15% powder rust rather wet powder and radish seeds, so that the treated seeds can be sown again to prevent radish whitening.

Hello, one way is to prepare in advance, that is, before planting radish, soak radish seeds in warm water at about 50 °, half an hour, you can also mix and stir with 15% powder rust rather wet powder and radish seeds, so that the treated seeds can be sown again to prevent radish whitening. The second method is pesticide prevention and remediation, avoiding excessive nitrogen fertilizer, appropriately increasing phosphorus and potassium fertilizer, paying attention to ventilation, abundant light, and reducing air humidity. If the radish is whitish, it can be diluted 2000 times with 15% powder rust rather wettable powder; 20% powdered rust net diluted 2500 times; 50% carbendazim wettable powder diluted 500 times, 70% methyl tobuzin wettable powder diluted 80 times; 40% polysulfur suspension diluted 500 times; 40% polysulfur suspension diluted 500 times; 50% sulfur suspension diluted 300 times; 2% wuyimycin aqueous solution 200 dilution times; Pesticide anti-120 aqueous agent diluted 200 times; 30% Teflin WP diluted 2000 times; 12% green milk copper emulsifiable concentrate diluted 600 times; 30% Teflin WP diluted 2000 times; 10% Shigao wettable powder diluted 3000 times; 40% DuPont Fuxing emulsifiable concentrate diluted 8,000 to 10,000 times; 25% Shibaoke EC diluted 2000 times; 50% Shibaogong wettable powder diluted 2000 times; 47% Garinone wettable powder diluted 600 times; 60% anti-mold treasure water-soluble powder diluted 1000 times.

The above pesticides can have a good effect on the treatment of turnips, spray radishes about two to three times with these agents, and spray them every seven to ten days.

Hello.

1. The sowing time of carrots.

Carrot spring sowing too early is easy to sprout, too late sowing leads to the succulent root swelling in the high temperature period of more than 25, producing a large number of deformed roots, carrot succulent root swelling suitable temperature in 18 25.

Based on production experience, carrots can be planted at an average daily temperature of 10 and an average night temperature of 7. Generally, the northern part of North China is sown in early April, and the southern part of North China is sown in late March. Central and South China can be sown in early March; Alpine areas such as the northwest and northeast can be sown from late April to mid to early May.

Carrot. 2. Carrot planting methods and technical requirements.

1. Seedling method.

During the seedling period, the seedlings were carried out twice, and the first time was carried out when there were 1 2 true leaves, and the inferior seedlings, weak seedlings and over-dense seedlings were removed. The second time is carried out at the time of 3 4 leaves of true leaves, and the seedlings are set after the seedlings, and the seedling spacing is 9 cm, and the row spacing is 15 18 cm.

2. Cultivating and weeding.

Cultivating and weeding is the key to the high yield of carrots, and herbicides can also be used to control weeds, commonly used 50% proweeds net 450kg, and 75kg of water weeding. In addition, pay attention to soil cultivation during cultivation to prevent the top of the fleshy roots from exposing the ground to form green shoulders.

3. Water and fertilizer management.

In order to make carrots abundant, water and top dressing 1 2 times throughout the growth period. The first time was carried out 5 7 days after the seedling setting, combined with watering, 3kg of ammonium sulfate, phosphorus and potassium fertilizer and 3kg per mu. The second time in 8 9 true leaves, that is, the early stage of fleshy root expansion, is also the period with the most water demand, combined with watering per mu to apply ammonium sulfate, phosphorus and potassium fertilizer, it is recommended to use fertile leaf water-soluble fertilizer, fast absorption, good effect, fertilizer utilization rate is higher than ordinary fertilizer utilization rate.

Fourth, carrots should be harvested at the right time.

Spring-sown carrots are sown in late March and generally harvested from mid-to-late June to early July, but can also be harvested in time according to market demand. When ripe, the leaves no longer grow, no new leaves are seen, and the lower leaves turn yellow. If there is 0 3 cold storage, it can be stored after harvesting, and it can be ** all summer.

Summary. The leaves of the radish which I planted turned white and was a disease.

The leaves of the radish which I planted turned white and was a disease.

Radish cultivation technology: Before land preparation and fertilization, it is necessary to plough deep as soon as possible after harvesting, fully freeze and dry the soil, break the rake level, and apply sufficient base fertilizer. According to the soil conditions, radish varieties can be selected, and large varieties with deep soil can be arranged, and the depth of cultivated land should be more than 33 cm; If the soil layer is shallow, you can choose small and medium-sized varieties with shallow soil, and the cultivated depth is about 25 cm for medium-sized species and about 15 cm for small species. The way of furrow cultivation varies according to the variety, soil quality, topography and local climatic conditions, the small radish in the middle of the tomb is cultivated with flat furrow in the place with less rain and good drainage, and the large radish has deep roots and large leaves, so it must be cultivated with high furrow.

In the Yangtze River Basin, both large and small radishes are mostly made of deep furrows and high furrows to facilitate drainage and irrigation. Generally high 20

To Chang Wang shouted 27 cm, furrow width l to 2 meters Ling Hui, ditch width Naye 40 cm. The root system of radish is well developed and needs to be fertilized sufficiently. Before land preparation, apply 100 quintals of farmhouse fertilizer such as rotting pigs and cow manure, 25 kg of superphosphate, 50 kg of compound fertilizer, and rake flat furrows after ploughing into the soil, so that the soil is loose, finely crushed and even, and the furrow surface is smooth.

The seedlings of radish grow rapidly after being unearthed, and the seedlings should be in time, and the principle is that the seedlings are in the morning, the seedlings are divided into stages, and the seedlings are set late. Morning seedlings, seedlings are small, and the roots of the seedlings are not prepared for burning when pulling out the seedlings; Late seedlings can be less than early seedlings, and the cultivation of celery is lighter due to the harm of a borer. In production, seedlings are generally interspersed 2 to 3 times.

At the first true leaf, the first seedling is mixed and rolled, and the weak seedlings, pathogens, deformed seedlings and seedlings that do not have the characteristics of the original variety are removed. When there are 2 to 3 true leaves, the seedlings are thinned for the second time. "Big belly" when each hole selects and retains a robust seedling with the characteristics of the original variety, that is, the fixed seedling, the rest is removed, and the number of seedlings left is 4,000 to 5,000 large and medium-sized varieties, and 10,000 small varieties.

Ask how to treat the white leaves of the robb leaves.

In the early stage of the disease or when the heart disease strain of Zhonghuai Ling is found, remove the diseased leaves and spray them immediately to prevent and control them. When spraying, it must be meticulous and thoughtful, especially the back of the old leaves. After spraying, the weather is dry and there is no need to spray again, if it encounters cloudy days or foggy air, then continue to spray every 5 7 days, and should be sprayed 1 time after rain.

Commonly used agents are: 72% frost urea, manganese-zinc wettable powder 600 times liquid, 70% ethyl aluminum, manganese-zinc wettable powder brigade Yuanyan Zhao agent 500 times liquid, spray 60 liters of liquid per mu, evenly spray the back of the leaves, do not re-spray or leak spray when dismantling the auspicious collapse, spray 2 3 times in a row, the effect is better.

Summary. The leaves of the white radish planted are white, and the mayor is sick, so it is sown late at the appropriate time to avoid the environmental conditions of the disease. Increase the application of organic fertilizer, combined with phosphorus and potassium fertilizer, and supplement trace element fertilizer. Timely field diseased plants to reduce pathogens. I hope I can help you and wish you a happy life and a <>

What should I do if the leaves of the planted radish are white?

The white radish leaves planted are white, and the mayor is diseased, so it is sown late at an appropriate time to avoid the environmental conditions of the disease. Increase the application of organic fertilizer, combined with phosphorus and potassium fertilizer, and supplement trace element fertilizer. Timely field diseased plants, Senshu to reduce pathogens. I hope it can help you, and I wish you a happy life and a kiss <>

The white dan and radish leaves are white, which is a long disease, and it is sown late at the appropriate time to avoid the environmental conditions of the disease. Increase the application of molded machine fertilizer, with phosphorus and potassium fertilizer, and supplement trace element fertilizer. Timely field diseased plants to reduce pathogens. I hope that the tape can help you, and I wish you a happy life and kiss <>

** The details are not very clear, like whiteflies. It is a pest.

The whitefly is also known as the little white moth. It belongs to the family Hemiptera whitefly. It is a worldwide pest, which occurs all over China and is an important pest of crops grown in greenhouses.

The host range is wide, cucumber, bean, eggplant, tomato, pepper, winter melon, bean, lettuce, cabbage, celery, green onion in vegetables. Peony flowers can be harmed by it, and can also harm 653 species of plants in 112 families, such as flowers, fruit trees, medicinal herbs, pastures, and tobacco.

Prevention and control of medicinal vitex: timely use of drugs in the early stage of whitefly, when there are 2-3 adults in each plant, especially in the stage of spotting.

In the early stage of whitefly, spray with 10% imidaxcarb 400-600 times, or 10% parametrix EC 1000 times, or 25% parametrix EC 1500 times. It can kill eggs, nymphs and adults, and when the amount of insects is large, a small amount of pyrethroid vinegar insecticides can be added to the solution. Generally, 1 time in 5-7 days, spray 2-3 times in a row.

Choose 1000 times of 25% acaricidal emulsifiable concentrate, 1500 times of 50% gram aphid emulsifiable concentrate, 2000 times of Uranus emulsifiable concentrate, and 3000 times of 21% emulsifiable concentrate, once every 5 to 7 days, spray 3 to 4 times.

20% methocarb emulsifiable concentrate 1000 times liquid + 10% imidacloprid water dispersible powder 2000 times liquid + anti-resistance solution 400 times solution, Wanling (methocarb) mixed with imidacloprid, using methocarb quick killing to make up for the delay of imidacloprid. The long-term efficacy of imidacloprid is used to make up for the shortage of dicarb, and the anti-resistance solution is added to further improve the efficacy, which can kill various insect whiteflies. 1 time every 5 to 7 days, spray 2 to 3 times in a row, you can get satisfactory results.

Fumigation method: The protected area can use dichlorvos smoke, 350-400 grams per 667 square meters, or 500 grams of 80% dichlorvos, pour dichlorvos on the wheat straw piles scattered in different sections of the greenhouse, light the smock shed for 1 night, with an interval of 5 to 7 days, and smoke 2 to 3 times. It is best to spray once every 1 to 2 days after fumigation.

In addition to the selection of pesticides, the spraying time is best carried out when the watering is not dry, otherwise it is not easy to spray on the body because the whitefly wings are dry and easy to fly.