Forget about pests and diseases in greenhouses

In recent years, with the increasing production area of ​​protected areas, high-density cultivation of facility agriculture and the planting of one crop year after year on the same land are conducive to the accumulation, growth, and reproduction of soil-borne pathogens, root-knot nematodes, and underground pests. According to the study, pathogenic bacteria and bacteria that are responsible for more than 90% of the fungal diseases of various vegetables are transmitted through the soil. If these pest control measures are not correct, they will seriously affect the yield and quality of vegetables. According to the practical experience in recent years, the main prevention measures are as follows: 1. Prevention of Soil-borne Pathogens In addition to thoroughly cleaning up the physical control of greenhouses, the main method is to use high-efficiency, low-toxicity and low-residue agents for prevention and control. Methods are as follows: Disinfection of pharmaceuticals: 1. Spraying or watering method: diluting the agent with clean water to a certain concentration, spray it on the surface of the soil with a sprayer, or directly pour it into the soil so that the liquid penetrates into the deep layer of the soil and kills the bacteria in the soil. . The commonly used pharmaceuticals include Miao Miao Jing, Miao Bacteria, Hymexazol, Geobacillus, Starricide, and Lactose. 2. Toxic soil method: Use proper amount of soil bactericide, mix toxic soil with fine soil according to pharmaceutical requirements, and apply it to planting furrows. High-temperature disinfection: After cleaning the greenhouses, apply basal fertilizer and some chemical fertilizers, then turn the ground flat and cover them well. Cover them with a transparent heat-absorbing film. The soil temperature can rise about 50-60°C and seal for 10-15 days. It is also possible to close the entire greenhouse before planting so that the maximum temperature in the shed can reach 70°C or more, the soil temperature can reach 60°C or more, and continuous sealing of greenhouses for 10 to 15 days can kill a large number of pathogens and pests. Air disinfection: high temperature stuffy shed is also a method of air disinfection. If combined with drug disinfection, the effect is better. The method is that after the high temperature sterilization, 45% chlorothalonil smoke agent can be used, 200-250 grams per acre shed, the drug is divided into 4 to 5 copies, evenly distributed in the shed. After being ignited with dark fire, the booth was closed for 24 hours. Or per 100 square meters with sulfur powder 150 grams, 500 grams of trichlorfon, 500 grams of sawdust, divided into several places on the iron, burning charcoal fire below. Ignite the shelter for more than 12 hours, then let it go. Second, the root knot nematode prevention symptoms and the law of occurrence: The disease mainly damage the roots, the formation of many large and small tumors (root). Cut open the root knot, there is a small milky white nematode. Above the ground, the symptoms of the light are not obvious, and those with severe growth are slow. The plants are relatively short and have poor growth. When the temperature is high at noon, the leaves are wilting, sooner or later or after watering, the wilt plants can return to normal. Root-knot nematodes Eggs excreted by old larvae live in the soil in oocysts or with scattered roots (diseases). When the temperature reaches about 10°C in the second year, larvae hatch, invade the roots, and stimulate root cells. Hyperplasia forms tumors. Root-knot nematodes are mainly transmitted by diseased soil and roots. The second is through irrigation water, farm tools, etc. When the soil temperature is 20°C, the nematode begins to harm, and it is most suitable for its activity at 25 to 30°C, and the larvae are dead at more than 40°C. The relative soil moisture content is 40% to 70%. If it is dry or too wet, its activity and reproduction are limited. Root-knot nematode disease occurs heavily in loose sand loam with poor ventilation. Comprehensive prevention and control measures: 1. Completely clean the greenhouse before soil preparation and remove the roots of the disease. 2, deep plowing more than 60 cm. 3, cover the plastic film and closed the greenhouse to make the ground temperature above 50 °C, continuous closed for about 15 days. 4. Nematode worms or 1.5 to 2 kilograms of seed agents can be used per mu, or 1 ml antibiotic editin can be used to treat the soil per square meter. Can be applied in combination with cultivated soil fertilization, or planting before planting in the ditch before planting. The above methods are integrated and the efficiency of prevention is above 95%. Third, nursery seedbed disinfection 1, seedbed soil disinfection: Take fertilizer soil preparation of fertilizer garden soil, if suspected with pathogens, they need to be disinfected and reused. Soil fungicides such as mycobacterial net or hymexazol or mycotoxin can be used to compare the dosage of the soil with the pesticide. When sowing, 2/3 of the soil is used to cover the bottom, and the rest of the pesticide covers the seeds. Or reconstitute nutrient nursery bed soil, the preparation of other ingredients at the same time, according to the amount of medicine per cubic meter directly into the nutrient soil and mix well. The specific method is to use 5 sieved net garden soil, 2 sieved decomposed lotus root fertilizers, and 3 decomposed mature horse dung, and add 1 kg of potassium sulfate compound fertilizer and 10 kg of plant ash to the rice seedlings per cubic meter of culture soil. The net 100 to 120 grams and carbofuran or nematode must be 100 grams. The nutrient soil is well equipped with nutrients or filled into the seedbed. 2. Seed Disinfection: Pour 5 times the seed volume in 55-60°C hot water in a clean pot, put the weighed seeds into the warm water, stir it with a small wooden stick, and stop stirring when the water temperature drops to 30°C. , Or soak with 1000 times potassium permanganate solution for 10 minutes, then rinse with water several times, then soak for 4 to 6 hours, remove and dry, use a net gauze or towel, placed at 25 ~ 28 °C Germination. The seeds can be sown when exposed.