Garlic is one of the most popular vegetables for people. The economic value of garlic sprouts and garlic bulbs is high, and pests in fields are light. In recent years, the cultivation area has been large, and Tongren Prefecture has reached 1,500 hectares. However, with the growing planting area, pests and diseases have also been increasing year by year, which has caused some impact on the income of vegetable farmers. Through many years of production practice, the author has basically figured out the main diseases of garlic in Tongren Prefecture. The current situation of China's agricultural network and its prevention and control technologies are described as follows: 1. Garlic blight is a relatively common disease in garlic production, and it is generally more serious in old areas than in new areas. On November 28, 2006 in Kaitian Village, Tongren City, the incidence rate of strains was 12.4%, and the incidence rate of leaf was 8.72%. At the same time, the incidence of strains was 9.82% and the incidence rate of leaf was 2.45%. 1000 hectares, the loss rate is about 10%. 1 symptoms. The disease mainly damages the leaves. The diseased leaves often produce lesions in the tip of the leaf or in the middle of the leaves, and rapidly expands. The lesions are irregular, water-soaked, pale or light yellow, and the edges are light green. When the humidity is high, the lesions rot and produce sparse white mold. 2 the law of occurrence. Mycelium and chlamydospores lived in the soil with the diseased bodies of the mycelium and the wintering germs produced zoospore in the following year. The primary infection was caused by rainwater spattering, and zoospores in the field produced zoospores, wind and rain, and irrigation. Water is the carrier of the disease and can spread around to re-infect the disease. The incubation period for the disease is very short. Once the conditions of temperature and humidity are appropriate, the disease spreads quickly and can destroy the whole field in a short time. The early rainy season, rainy days, and rainy days tend to cause illness and serious illness. When a plant grows weak or overly luxuriant, it gets worse. 3 prevention measures. High ridge or sorghum cultivation, good drainage gutters, autumn high-yielding cultivation techniques for garlic to prevent rain, attention to reasonable application of nitrogen fertilizer, do not apply partial, excessive application of nitrogen fertilizer, increase phosphorus, potassium fertilizer; timely irrigation, cultivator weeding, prevent wet Gas stagnation; found the initial diseased plant to remove or remove diseased leaves in time, reduce the field bacteria source, completely clear the field sickness, concentrated burning or deep buried; early onset of chemical control, the choice of 25% metalaxyl WP can be used 600 times liquid, or 64% ?f Mn Zn wettable powder 500 times, or 40% triethylphosphonate wettable powder 200 times. 2. Garlic coal spot disease generally has higher incidence of planting in dry fields than slope soil. The area of ​​400 to 500 hectares in the entire Tongren area is estimated to be between 8% and 17%, with a loss rate of around 1.2%. 1 symptoms. It mainly damages the leaves. The leaves at the beginning of the disease develop pale spots, and then gradually expand into oval or spindle-shaped lesions parallel to the veins. The lesions are yellow in the center, red-brown on the edges, and yellow on the outside. When the conditions are appropriate, the lesion rapidly spreads along both ends, especially in the direction of the tip, causing the tip to dry and twist. When the humidity is high, a dense layer of deep olive-brown mold develops on the surface of the lesion and becomes powdery when dried. In severe cases, several lesions were contiguous, causing leaf blight and even plant death. 2 the law of occurrence. Mycelia and conidiospores are overwintering on diseased bodies. Fertilizers can also be carried. The first year of infection with conidia, conidia in the field can spread with air flow, intrusion by stomata. Disease incubation period is short, and when conditions are right, it develops rapidly. Severe onset in the 3rd to 4th month, the disease will increase when the plant growth is weak. 3 prevention measures. Selection of disease-resistant varieties; timely sowing, rational close planting; strengthening the cultivator weeding to maintain robust plant growth, deep digging drainage ditch, drainage in time after rain, to prevent moisture retention in the field; chemical control can be used 65% of dexamethasone soluble powder 500 times, Or 80% mancozeb soluble powder 800 times, or 50% polymyxin WP 800 times evenly spray. 3. Garlic white rot, also known as Sclerotinia, is commonly known by farmers as garlic rickets. According to the 2006 census, the Tongren area has an area of ​​more than 800 hectares, and the incidence of land mass accounts for about 20%. The average mortality rate is 7.8%. The mortality rate of Tongtian Village in Tongren County is 8.2%. The mortality rate in Yuping Tianping Village is 7.4%. The occurrence of garlic is one of the important factors restricting the production of garlic. 1 symptoms. The damage to the leaves, leaf sheaths and bulbs is the first to form a disease center in the field and gradually spread to all fields. At the early stage of disease, the tips of the outer leaves of the plants turn yellow and then extend downwards to the leaf sheaths and inner leaves, causing the plants to grow poorly, and the whole plant turns yellow and dead in the later period. Bulb disease, resulting in watery lesions, a large number of long white mycelium layer, the disease was white rot, the late mycelium layer produced sesame size black sclerotia, and finally the whole bulb becomes black rot. 2 the law of occurrence. The disease sclerotia wintered in the soil and the body of the disease, the second year of spring sclerotia germination, directly invade the garlic tissue. Sclerotia are transmitted through rainwater, irrigation water, and agricultural activities. The soil sclerotia stimulated the germination of the hyphae in the event of root exudates, and it directly invaded the roots and near the ground to cause field diseases. After the central diseased plant was found in the field, hyphae spread from plant to plant, resulting in the formation of a nest of diseased plants. The optimum temperature for sclerotia germination is 20°C, and the soil moisture is conducive to sclerotial germination. Even the field (ground) is heavy. 3 prevention measures. Choose disease-free garlic seeds; build drainage ditch to reduce the humidity in the field; apply basic fertilizer, apply nitrogen, phosphorus, and potassium to balance top-dressing; remove diseased plants in the field in time to remove diseased bodies; when there are sporadic diseased or disease centers in the field, Timely application of 50% carbendazim WP 500 times, or 50% ethidium bromide WP 1000 times, or 50% urea urea wettable powder 1500 times, sprayed once every 7 days, even spray 3 times, it is better to control the spread of white rot. Shanghai J.Shine Co.,Ltd , https://www.jshinechem.com