Characteristics of garlic disease and its prevention and control in this year

Due to the long-term influence of drought, the root system development of garlic in many places is poor, the freezing resistance of garlic seedlings is weak, and the occurrence degree of various diseases is more serious than in previous years. The author recently visited Cangshan, Jinxiang, Shanghe and other garlic towns in Shandong, and concluded that the current garlic production should focus on the prevention and control of the following four major diseases:

Garlic virus disease in garlic production in the past, garlic virus disease was ignored by many garlic farmers. This year, due to the influence of the dry weather in the previous period, the occurrence of garlic virus disease in some areas is more serious than in previous years. At the initial stage of the disease, intermittent yellow stripes appeared along the leaf veins, then turned into yellow and green stripes, the plant was dwarfed, and the heart leaves were surrounded by adjacent leaves, showing curly deformities and could not protrude. Sometimes yellow-white and green stripes appear on the leaves, sometimes the whole plant is yellowed and dwarfed, the stem is damaged, and the internodes are shortened. Prevention and control methods: (1) in the last harvest of garlic, timely removal of disease and debris, concentrated burning or deep burial; (2) reasonable fertilization and rotation. It is suggested that no-tillage fertilizer should be used for base fertilizer or no-tillage flushing fertilizer for garlic. Through the use of no-tillage fertilizer or no-tillage flushing fertilizer, the soil consolidation can be broken, the soil can be loosened, which is beneficial to the growth of garlic root system and make the whole garlic seedling strong. (3) Pesticide control: spraying 20% virus Kexing 400x liquid and 4000 times liquid Shuofeng at the initial stage of the disease. You can also use 1.5% Zhiyiling emulsion 1000 times liquid plus 3000 times liquid Shuofeng 481x and 800x liquid high-energy red potassium, once every 6-7 days, spray 3 times 4 times in a row.

Second, garlic blight is the main disease of garlic. Continuous cropping plots, heavy sticky, poor drainage, easy to stagnant water, planting density is too high, coupled with the rainy weather. Garlic blight occurs almost every year, and the yield can be reduced by 30% to 40% in the event of the disease. The disease is usually more serious in rainy years in summer. The blight can damage not only leaves, but also roots, stems and garlic bolts, especially pseudostems and bulbs. At the beginning of the disease, the disease first occurred in the tip or middle of the leaf, and it was a dark green water-immersed spot at the beginning. When it reached about half of the leaf, the whole leaf turned yellow, drooping and soft rot. When the air is moist, the disease produces a sparse white mildew. Prevention and control measures: (1) when using base fertilizer, properly increase the application of organic fertilizer, combined with organic fertilizer, use no-deep tillage compound fertilizer 80 kg per mu; in the garlic green and seedling stage, combined with irrigating and no-tillage flushing fertilizer 25kg / mu, make the soil loose and aerate, reduce surface stagnant water; (2) Chemical control: Bangjiawei 500x liquid and 4000 times liquid Shuofeng 481can be used. Or spray 72.2% chloramphenicol hydrochloric acid salt solution with 4000 times liquid Shuofeng 481, once every 7 days, twice in a row.

Third, garlic rust mainly harms leaves and pseudostems. The disease is an oval chlorotic spot at the beginning, and then a round or oval slightly protruding pile of summer spores appears under the epidermis, and orange powdery matter, that is, summer spores, is scattered after the epidermis is ruptured; there is a yellow halo around the disease spot, and when the disease is serious, the disease spot causes yellow withering of the whole leaf, and the plant dies ahead of schedule. In the later stage, a black winter spore pile with unbroken epidermis is produced on the unbroken summer spore pile. Prevention and control methods: (1) select disease-resistant varieties. For example, purple garlic should be selected to avoid the mixing of onion and garlic; (2) pay attention to cleaning the countryside in order to reduce the initial infection source; (3) timely late sowing, prevent late de-fertilization, avoid partial application of nitrogen fertilizer, reduce watering times, and put an end to flood irrigation; (4) Pesticide control: choose Bangjiawei 4000000x liquid plus 4000 times liquid Shuofeng 481g You can also use Puxing (25% triazole copper wettable powder) 1000mm 1500 times liquid plus 4000 times liquid Shuofeng 481for foliar spray, once every 7 to 10 days, twice in a row.

Garlic leaf blight is one of the main diseases of garlic, which occurs in all garlic producing areas. If it is not controlled in time, the yield can be reduced by 50% to 80%. It mainly harms leaves or pedicels. The leaves were infected, showing white dots at first, and then expanded into oval gray-white or grayish-brown spots, which produced black mildew, and the diseased leaves died when the disease was serious. Prevention and control methods: (1) choose the soil with flat terrain, deep soil layer and soft tillage layer to grow garlic. It is suggested that 80kg of no-tillage fertilizer per mu or 1kg of no-tillage 1kg / mu mixed with 100 kg of common compound fertilizer should be used as base fertilizer. In the green period of garlic, no-tillage flushing fertilizer of 30kg per mu was applied with water. (2) Chemical control: foliar spraying was carried out with 1000 × 2000 times of prochloraz (prochloraz manganese salt) and 4000 times of Shuofeng per mu, or 2 times of 20% phenylether miramine microemulsion plus 800 times of high energy red potassium, once every 7 days for 3 times.