Excuse me, is there any cure for this cabbage?

This cabbage is hopeless.

Cultivation techniques of Chinese cabbage (Chinese cabbage).

Seedlings: 5 to 6 days after the emergence of seedlings, the first seedlings, to the weak and strong, strip sowing seedlings spacing 2 to 3 cm; When the Chinese cabbage has 3 to 4 leaves, the seedlings of the strip sowing plot are 8 cm, and about 3 plants are left in each hole when the hole is sown; After another 5 to 6 days, the third seedling is sent.

Seedling: The seedlings grow for about 25 days to reach the cluster stage, and the seedlings are set according to the distance between 50 to 60 cm, and about 2,000 seedlings are left in 667 square meters. If the lack of seedlings is found, it should be replanted in time, and the seedlings should be watered in the afternoon or cloudy day on a sunny day.

Cultivating and weeding: 3 times of tillage, respectively after the second seedling, after seedling setting and in the middle of the rosette. Cultivating combined with weeding.

Reasonable watering: If the bottom moisture is insufficient, water in time after sowing to ensure that the seedlings are strong and strong. After thinning seedlings and setting seedlings, water 1 water each. Watering at the beginning of the rosette promotes the growth of the trees. During the balling period, watering should be carried out in combination with top dressing, and the amount of watering should be large and uniform. In the later stage, appropriate water control promotes the core wrapping.

Timely topdressing: 667 square meters of rosette stage topdressing nitrogen, phosphorus, potassium compound fertilizer 15 to 20 yuan. At the beginning of balling, 667 square meters of nitrogen, phosphorus and potassium compound fertilizer were topdressed with 30 to 40 kg.

No more topdressing within 20 days before harvest. Combined spraying at the rosette stage with 1 spray of foliar fertilizer every 7 to 10 days for a total of 2 to 3 times, using a mixture of urea and potassium dihydrogen phosphate, sprayed after 16:00.

Harvest: After mid-November, Chinese cabbage basically stops growing and enters the harvest period. After the beginning of December, it should be harvested in time to prevent frost damage.

Pest control. Principle: prevention first, comprehensive prevention and control, give priority to agricultural control, physical control, biological control, and chemical control. Agricultural prevention and control selects excellent varieties, cultivates strong seedlings, sows seeds in a timely manner, rotates crop stubble, strengthens management, and cleans the countryside.

Physical control. Use yellow armyworm boards to lure away aphids, whiteflies and other pests.

Sweet and sour liquid inducement: sweet and sour liquid preparation is 3 parts sugar, 3 parts vinegar, 1 part of high liquor, add 10 parts of water, and then add 90% crystal trichlorfon parts, mix evenly and put it into a large bowl, place 1 per 80 square meters, cover it during the day, open it at night, and change the sweet and sour solution once every 10 to 15 days.

Biological control: release of natural enemies, such as predatory mites, parasitic wasps, etc.; the use of biopesticides such as Bacillus thuringiensis, avermectin, etc.; Biological fertilizer is applied.

Chemical control. Aphids and whiteflies are alternately sprayed with 10% imidacloprid wettable powder 1000 to 1500 times, or 10% acetamiprid 1000 to 1500 times, sprayed 2 to 3 times, paying attention to the back of the leaves. Brassica and Spodoptera exigua were sprayed alternately with cypermethrin 2000 times or cyhalothrin 3000 times before the 3rd instar.

Downy mildew is sprayed 1500 times with 25% di-noxinyl amine suspension, sprayed once in 7 to 10 days, and continuously controlled 2 to 3 times. Soft rot is sprayed with 4000 times of 72% agricultural streptomycin sulfate wettable powder, or 1000 times of 3% Zhongshengmycin wettable powder.

Yes, downy mildew and black rot.

It is recommended that you prevent bacteria and fungi together, and Chinese cabbage mainly controls Chinese cabbage downy mildew, Chinese cabbage anthracnose, and Chinese cabbage bacterial diseases. It can be sprayed with frosturea·manganese-zinc + mesomycin + prochloraz manganese salt plus potassium dihydrogen phosphate, and sprayed continuously once every 7 days.

This cabbage can be sprayed with Bordeaux liquid.

Bordeaux liquor is an inorganic copper bactericide. It is a sky blue gelatinous suspension formulated from about 500 grams of copper sulfate, 500 grams of hydrated lime and 50 kilograms of water. The ingredient ratio can be appropriately increased or decreased as needed.

It is generally alkaline and has good adhesion properties, but it is suitable to be used for a long time or made of dehydrated Bordeaux powder, and then mixed with water when used.

The solution is a protective bactericide, which inhibits the spore germination or hyphal growth of pathogenic bacteria by releasing soluble copper ions. Under acidic conditions, when a large amount of copper ions are released, it can also coagulate the cell protoplasm of pathogenic bacteria and play a sterilizing role. In the case of high relative humidity and dew or water film on the leaf surface, the efficacy is better, but it is easy to cause pesticide damage to plants with poor copper tolerance.

It has a long effective period, and is widely used in the prevention and control of vegetables, fruit trees, cotton, linen, etc., and has a particularly good effect on downy mildew and charcoal disease, potato late blight and other leaf diseases.

Bordeaux liquor is a protective biocide. The active ingredient is basic copper sulfate, which can effectively prevent the germination of spores, prevent the infection of pathogens, and can promote the leaf color to be dark green, grow robustly, and improve the disease resistance of the tree. The preparation has the characteristics of wide bacteriological spectrum, long duration of effect, no resistance to pathogens, low toxicity to humans and animals, etc., and is a fungicide with the longest application history.

Bordeaux liquid itself does not have a bactericidal effect, and when it is sprayed on the surface of the plant, it is adsorbed on the surface of the crop due to its adhesive properties. In the process of metabolism, plants will secrete acidic liquid, coupled with the acidic substances secreted by bacteria when they invade plant cells, so that a small amount of basic copper sulfate in Bordeaux solution is converted into soluble copper sulfate, thereby producing a small amount of copper ions, which will coagulate the proteins in the cells after entering the bacterial cells. Copper ions can also destroy certain enzymes in their cells, thus preventing the normal metabolism in the bacterial body.

Under the influence of these two effects, the bacteria can die.

Prevention and control objects. To prevent and control early apple defoliation, charcoal disease, and ring pattern disease, you can start to spray lime doubling Bordeaux liquid 200 to 240 times after apple flowering, spray once every half month, and alternately use with other fungicides, a total of 3 to 4 times. To prevent and control apple rot disease (ring pattern disease, charcoal disease), you can spray lime doubling or multi-volume Bordeaux liquid 200 times 10 to 15 days before the appearance of diseased fruit in previous years, spray 1 time every 15 to 20 days, spray 3 to 4 times, and stop using 25 days before fruit picking.

To prevent and control apple mildew heart disease, 200 times of lime multiple-type Bordeaux solution should be sprayed at the beginning of the apple budding period. To prevent and control apple and pear rust, you can spray 160 times of lime equivalent Bordeaux liquid on the juniper cypress around the apple orchard. To prevent and control grape black disease, charcoal disease, and downy mildew, you can spray a small amount of lime Bordeaux liquid 160 times, spray 1 time every 12 to 15 days, a total of 2 to 4 times.

After the rainy season, Bordeaux juice is used to control grape diseases.

This one is downy mildew of cabbage, ** with some difficulty.

Relationship between temperature and downy mildew.

The average temperature at which the disease tends to prevalence is 16, because this temperature is conducive to both the germination and invasion of sporangia and the development of mycelium after invasion. The fastest development of lesions is above 20 temperatures, especially at high temperatures (24 25) that tend to develop into yellow-brown blight.

Downy mildew of cabbage is caused by downy mildew infection of the cruciferous family, which can occur from the seedling stage to the adult stage of cabbage. At the seedling stage, a white frosty mold layer appeared on the back of the leaf at the beginning of the disease, and there were no obvious symptoms on the leaf surface, and the seedlings and cotyledons turned yellow and died in severe cases. At the adult stage, white downy mildew is produced on the back of the leaves, and pale green lesions appear on the leaf surface, which gradually turn to yellow or yellow-brown, and the expansion of the lesions is limited by the leaf veins to form a polygonal shape.

The environmental conditions were suitable during the centering stage, the lesions increased rapidly, and the leaves dried up layer by layer from the outside to the inside. The disease tends to occur in the low temperature stage from winter to early spring, and does not form balls in the early stage.

Prevention and treatment can be used in the early stage of the disease, 90 triethylphosphonate aluminum wettable powder 800 times liquid, 58 methamphelate manganese zinc wettable powder, 70 ethyl manganese wettable powder, 75 chlorothalonil wettable powder, 65 dycozeb zinc wettable powder, 50 dichlorazim wettable powder, 50 grams of myctodan wettable powder 500 times liquid spray, once every 7 10 days, continuous prevention and control 2 3 times. In addition, the diseased leaves should be collected and processed after the cabbage is harvested.

The downy mildew of Chinese cabbage, in some places is also called running horse dry, frost leaf disease, branches, white mold, dragon head disease, can occur in the seedling stage and adult stage of Chinese cabbage, mainly leaves, one of the three main diseases of Chinese cabbage. The onset occurred mostly in spring and autumn in the Yangtze River Basin, while in North China it mostly occurred in April, May and August and September.

1. Symptoms of downy mildew of Chinese cabbage.

After Chinese cabbage is infected with downy mildew, it first starts from the lower leaves of Chinese cabbage, and will produce water-soaked, yellowish polygonal lesions on the leaves, and begin to expand gradually, and then turn yellow-brown, and in severe cases, the leaves are dry and inedible.

Second, the prevention and control measures of downy mildew of Chinese cabbage.

Seed treatment: The seeds should be treated before the Chinese cabbage is planted, and when disinfecting the seeds, it is recommended to use 25% of the seed weight of the hypnotic wettable powder, or 75% chlorothalonil wettable powder and other dry powders to dry mix the seeds.

Pesticide treatment: out of the seed treatment, in the growth period to spray chemical pesticides in a timely manner, mainly in the prone to occur (mainly in the cotyledon stage and the middle and late stage of balling) it is recommended to spray 2% pyrimidine nucleoside antimicrobial water agent 200 times of the solution, spray every 7 days, to spray 2 3 times continuously.

Third, the prevention and control of cabbage diseases and the improvement of yield must be done in the following points:

1. Select improved varieties and select high-yield and high-quality Chinese cabbage varieties, which is a prerequisite for high yield of Chinese cabbage.

2. Balanced fertilization, increasing phosphorus and potassium fertilizer during top dressing, can improve the disease resistance of Chinese cabbage plants, and can also ensure the nutrition of Chinese cabbage in the growth period and enhance disease resistance. When planting, high furrow seeding is advocated, which is conducive to drainage, prevents waterlogging and reduces humidity, which can also reduce the occurrence of downy mildew and soft rot.

3. Stubble arrangement, the stubble before planting Chinese cabbage is suitable for eggplant fruits, melons, and onions, and it is necessary to avoid continuous cropping with cruciferous vegetables, or adjacent cropping.

4. Seed disinfection, before the Chinese cabbage is sown, the seeds can be disinfected, the usual method is to use warm soup soaking method, before sowing with 50 warm water to soak for 20 30 minutes, and then immediately move into cold water to cool down, and then dry and sow seeds, with this method can effectively prevent the occurrence of Chinese cabbage black spot, black rot, anthracnose and other diseases.

5. If Chinese cabbage is sown too early, some diseases such as downy mildew, virus disease, and soft rot usually occur more seriously. If it is sown late, the disease occurs relatively lightly, but there will be a core is not real, and it will affect the yield, so the sowing time is generally in the "beginning of autumn" after 2 or 3 days, and the occurrence of the disease is relatively light.

6. Strengthen field management and avoid stagnant water in the field.

In order to avoid the occurrence of downy mildew of Chinese cabbage, from the selection and disinfection of seeds, we must pay attention to fine management, any vegetable planting is the same, accurate field management is an effective measure to avoid the occurrence of diseases.

Cataplexy will bring great harm to cabbage seedlings, and can be sprayed with mycocarb hydrochloride or methamethoxaline to prevent and control; Soft rot will harm cabbage rhizomes, leaves, treasure pieces and other parts, and can be sprayed with agents such as thiamydone and chunleimycin**.

1. Cabbage cataplexy.

Cataplexy is common in all kinds of vegetables, harmful to the seedling stage, the seedling root appears water-stained lesions at the onset of the disease, gradually shrinks into a line with the change of the disease, and then folds down to the ground, if the soil moisture is larger, the disease location will also appear white cotton wool.

Prevention and control methods: This disease mainly appears in the high temperature and rainy season in the south, and it is also easy to develop in the low temperature and high humidity environment at the seedling stage. Disinfect seeds and soil before planting, and spray with mycocarb hydrochloride or methamethoxamine after the onset of disease.

2. Cabbage black rot.

Black rot can occur on both cabbage seedlings and adult plants, and the leaves of the seedlings appear water-soaked lesions, the roots turn black, and finally wilt and die. When the adult plant is sick, the leaves appear diseased spots or leaf veins turn black, and the diseased spots become V-shaped yellow-brown withered spots with diffusion, which gradually spread throughout the bulb, and finally are easy to crack when dry, and rot when the humidity is high.

Prevention and control methods: In summer, the climate environment of high temperature and high humidity is prone to disease, and improper continuous cropping and fertilization will also lead to disease. The same planting disinfection treatment of soil and seeds, scientific and reasonable fertilization, balanced matching of various fertility, difenoconazole and thiomycete copper spraying can be used for prevention and control when the disease occurs.

3. Cabbage soft rot.

Cabbage soft rot can occur at the seedling stage, rosette stage, and core stage, and can occur in different parts, such as rhizomes, leaves, and treasures. In the end, it all causes different parts to rot and die.

Prevention and control methods: In the rainy season, excessive watering and leaf cracks and wounds are prone to disease, avoid continuous cropping with Solanaceae and melon vegetables when planting, and avoid planting on low-lying, sticky soil plots. Disinfect the soil and seeds before planting, uproot the diseased plants and take them out of the field in time after the onset of the disease, and then spray them with thiamethone and spring leimycin agents.

4. Pests. The insect pests of cabbage mainly include cabbage moths and aphids, which eat mesophyll or suck the juice of leaves, and finally cause the leaves to dry up and shrink, which will seriously cause death to cabbage.

Control methods: often remove weeds, reduce the living environment of insects, and also use greenhouse technology to close for 3-5 days, so that high temperature kills insecticidal sources, and can be controlled with pesticides.