Prevention and control of black rot of cauliflower when veins turn black, dry or rotten

Besides cauliflower, black rot of cruciferous vegetables such as cabbage, cabbage and radish is a bacterial disease caused by Xanthomonas aeruginosa. In recent years, the black rot of cauliflower is increasing year by year, which seriously affects the yield and quality of cauliflower.

Black rot of cauliflower

First, symptoms:

After the cauliflower was infected by the pathogen, the disease began from the leaf edge, and the V-shaped yellow-brown spot was formed from the apex and both sides of the leaf vein. When the air was dry, the diseased part was dry and crisp, and when wet, the diseased tissue rotted, and the vascular bundles of the stem and root also blackened.

Second, prevention and control measures:

1. Seedbed disinfection: every square meter of seedbed with 30 ml of formalin 2.5 kg of water, then spray with a sprayer (to the sprinkler), spray while turning the soil, spray evenly, cover the agricultural film, uncover the agricultural film after a week, turn the soil several times, fully volatilize formalin for about 5-7 days.

two。 Seed treatment: cauliflower seeds can be soaked in 50% Dysenamine solution 200 times for 15 minutes, then washed, dried and sowed. Soaking seeds in warm soup will affect the germination rate of cauliflower, so you should use it with caution and try not to use it.

3. Nursery bed management: if the seedlings are raised in summer, the seedlings should be raised in protected areas, covered with sunshade nets to prevent sun exposure and Rain Water erosion. After the seedlings are unearthed, the seedlings should be checked frequently to ensure that the seedlings are uniform and strong. If the seedlings are diseased, they should be pulled out in time and sprayed for prevention and control. In the whole seedling period, it is necessary to control diseases and insect pests such as blight, quenching disease, cabbage pest and so on.

4. Crop rotation: the rotation of cauliflower and non-cruciferous vegetables for more than 2 years can solve the problem of soil bacteria. In order to eliminate or reduce the pathogens in the soil, the soil was deeply sunburned for 10 to 20 days before planting, so as to accelerate the ripening of plant residues and the death of pathogens in the soil.

Cauliflower management

5. Fertilizer and water management, mid-tillage weeding: seedling planting, slow seedling, adequate seedling fertilizer, topdressing 2 or 3 times during the growth of cauliflower to prevent premature senility and enhance disease resistance. Avoid flood irrigation to reduce the chance of germ transmission. Ploughing and weeding in time according to soil moisture.

6. Pest prevention and control: in addition to directly causing losses, pests also provide pathogens with ways to infect from wounds. Therefore, in plots with many pests, black rot is also serious. To prevent diseases, we must first control pests, especially cabbage insects and diamondback moths.

7. Disease prevention and treatment: after the occurrence of black rot cauliflower in the field, it should be controlled in time. 500 times of Dysenamine can be used, and 200 mg / kg of agricultural streptomycin, streptomycin sulfate and neoptomycin are available, which has obvious control effect. In addition, 50% methyl topiramate and 50% carbendazim wettable powder are also very effective.