What symptom does eggplant verticillium wilt have? What are the prevention and control measures?

In recent years, with the adjustment of rural industrial structure, due to years of continuous cropping in some areas, soil pathogens have increased year by year, and eggplant Verticillium wilt has become increasingly serious, affecting the yield and quality of eggplant and becoming one of the obstacle factors in eggplant production. So, what are the symptoms of eggplant Verticillium wilt? What are the prevention and control measures?

What's the matter with eggplant Verticillium wilt?

Eggplant Verticillium wilt, also known as half crazy, black heart disease, Fusarium wilt, is an important disease of eggplant. Eggplant can be infected at seedling stage, and most of them show symptoms after fruit setting in the field.

The pathogen of eggplant Verticillium wilt is Verticillium dahliae. The genus Verticillium subphylloides. The pathogen first grew white hyphae on the culture medium, and then formed a large number of black sclerotia conidiophores with 3-4 branches in each round; the conidia were colorless, unicellular and long oval. The optimum temperature for the growth of the pathogen was 22.5 ℃, and it could still grow under the condition of 30 ℃. The optimum pH value for growth is 5 minutes 37 minutes 2, and under the condition of pH 3 minutes 6, the host range of good growing bacteria is wide, which harms not only eggplant, but also 38 families and 180 species of plants, such as pepper, tomato, potato, melons and other Solanaceae vegetables.

What are the symptoms of eggplant Verticillium wilt?

Most of the diseases began to occur after the fruiting of door eggplant. The leaves of the lower half of the plant were yellowed near the petiole and between the veins, and gradually developed into a half leaf or the whole leaf turned yellow, the leaf edge curled slightly upward, and sometimes the disease spot was limited to half of the leaves, causing leaf distortion. High temperature in sunny days, wilting of diseased plants, recovery at night or rainy days, when the disease develops rapidly, the whole leaves often turn yellow, turn brown and die.

3. Control measures of eggplant Verticillium wilt

1. Select disease-resistant varieties, such as Changqie No. 1, Longza eggplant No. 1 and so on. If the disease-free seed is selected, the seed can be collected from the disease-free field or withered from the disease-free area. Before sowing, to disinfect the seeds, soak the seeds in 55 ℃ warm water for 20 min or soak the seeds with 70% pentachloronitrobenzene powder at a dosage of 0.2% of the seed weight.

two。 The nursery bed with disease-free soil or bed soil disinfection should choose the land with high dry terrain, convenient drainage, fertile soil and free of pathogens. Before sowing, the seedbed soil should be fully turned in the sun, compost should be fully rotten, and the seedbed should be disinfected with 50% carbendazim wettable powder or 70% pentachloronitrobenzene at a dosage of 8: 10g per square meter.

3. Implement crop rotation and stubble. Rotation with rice for 1 ~ 2 years and rotation with non-Solanaceae vegetables for 4 ~ 5 years.

4. The acupoint plate was used to raise seedlings. One plant at a point. The plant is evenly distributed, the nutrient of the nutrient soil is sufficient, and the permeability is good, so the vegetable seedling is strong and the root system is well developed. when the seedling is planted, it generally does not hurt the root or slightly, and there is no return to the seedling stage after planting, which enhances the disease resistance.

5. The technique of grafting seedling was applied. According to systematic observation and data records, eggplant grafted seedlings have strong resistance to Verticillium wilt, and the incidence can be reduced by 4.7% to 34.5%.

6. Applying rotten organic fertilizer, and applying mixed fertilizer of nitrogen, phosphorus and potassium, ploughing and cultivating soil in time to promote root growth.

7. When diseased plants are found, they should be pulled out in time and taken out of the vegetable field to be buried or burned.

8. Chemical control. During planting, 50% carbendazim wettable powder 5kg was used to stir fine soil 100kg to make medicinal soil, which was scattered in the planting hole for preventive treatment. After planting, 70% dimethazone wettable powder, 50% benomyl wettable powder and 50%DT fungicide were sprayed on the root and ground, or irrigated with root. The drug is usually applied every 10 to 14 days. In the early stage of the disease, 50% carbendazim wettable powder 500 times liquid spray treatment, or 70% methyl topiramate 500 times solution for root irrigation treatment, 7 times 10 days spray (irrigation) once, continuous spray (irrigation) 2 times 3 times.