First, implement crop rotation.
According to the requirements of different vegetable crops, it is better to plant at certain intervals, and it is best to implement rice-upland rotation, such as planting one-season rice after pepper stubble or planting aquatic vegetable lotus root. Rotation has a good effect on preventing soil-borne diseases.
The second is to use grafting planting.
Grafting and planting disease-resistant rootstocks to improve the disease-resistant ability of vegetables. Watermelon, cucumber, tomato and eggplant are often harmed by deadly diseases, such as verticillium wilt, Fusarium wilt, root rot and bacterial wilt. Once they get sick, they will face crop failure and crop substitution. Grafting can prevent these diseases well. According to the measurement, the incidence rate of watermelon, cucumber, tomato and eggplant after grafting is zero, while the incidence rate is 90% after grafting watermelon for three years and 30%-50% after grafting cucumber for three to five years.
Third, soilless culture.
A method for planting vegetables with nutrient solution instead of soil. The method has the advantages of saving water and fertilizer, high yield, good quality, no pollution, fast production and good benefit, and can fundamentally solve the problem of soil-borne continuous cropping diseases, especially suitable for industrial production. Soilless culture is widely used in the production of a variety of vegetables without geographical restrictions, but the technical requirements are strict.
Four. Disinfect with chemicals
It is also effective to disinfect the greenhouse with chemicals after the vegetables are stubbled in the greenhouse. For example, to prevent fungal diseases, 30% soil bacteria can be sprayed with 500-800 times solution; You can also spray 500- 1000 times the solution of Genputulin or hymexazol, or evenly sprinkle an appropriate amount of fine soil according to 3-5 kilograms of medicine per mu. To control bacterial diseases such as bacterial wilt and soft rot, 80% hydrocortisone 1000 times solution, 72% agricultural streptomycin 3000-5000 times solution or copper complex can be selected for spraying. These chemicals should be used to disinfect the soil before sowing.
Five, high temperature stuffy shed
High-temperature greenhouse is an economical and effective method to prevent and control vegetable continuous cropping diseases, that is, using solar energy for high-temperature treatment, disinfection and sterilization. The specific method is the high temperature stage from June to September every year, usually from early July to late August, with low cost, little pollution, simple operation and good effect. Use the gap between two crops, or combine with soil preparation and fertilization to replace crops to kill bacteria in basic organic fertilizer. Can be carried out according to the following steps:
1. Soil preparation and fertilization. Combined application of farm manure can improve and maintain the ground temperature, and the disinfection effect is better. After the land is leveled, ridges or high and low ridges should be made to form a certain space between the plastic film and the ground, which is conducive to raising the ground temperature.
2. Irrigation. Soil water content is closely related to disinfection effect. Too high water content is not conducive to raising ground temperature, too low water content is not conducive to disinfection effect, and the disinfection effect is the best when the maximum water capacity in the field is 60%.
3. medication. Inject chloropicrin into the border, dig a hole (10- 15 cm deep) every 50 square centimeters, inject 4 ml into each hole, and then cover it with plastic film. Spray fungicides and pesticides on the surface of objects in a closed greenhouse once.
4. Close the greenhouse and cover it with plastic film and plastic film. According to the measurement, during the greenhouse period, the temperature in the greenhouse can reach above 52℃, the highest ground temperature below the surface 120 cm can reach 70℃, and the sterilization rate can reach above 80%. Most pathogenic bacteria, such as Sclerotinia sclerotiorum, Rhizoctonia solani, Verticillium Wilt and Phytophthora blight, are not resistant to high temperature, and can be killed by heat treatment for about 10 day, while soil-borne diseases such as root rot, clubroot and Fusarium wilt are distributed in deep soil layers, and good results can be achieved only after treatment for 30-50 days.
In a word, the time of disinfection and sterilization in greenhouse should be determined according to the heat resistance of crops and the corresponding pathogens in greenhouse. The method of high temperature sterilization in greenhouse can generally make the disinfection effect lasting.
China Agricultural Information Network-Integrated Control of Continuous Cropping of Vegetables in Greenhouse