Sunflower planting: sunflower sclerotinia disease how to control?

How to prevent and cure sunflower sclerotinia disease? Please introduce the causes and control methods of sunflower Sclerotinia sclerotiorum can occur from the beginning of seedlings to before the formation of disk. In the seedling stage, the disease mainly occurred at the base of the stem, water-immersed disease spots were formed around the stem, white flocculent hyphae grew when it was wet, the disease part contracted and thinned after drying, black sclerotia formed in the stem, and the plant withered. In the adult stage, the disease mainly occurred at the base of the stem, showing a light brown wet spot, which gradually expanded to the stem of the whole plant. In the later stage, the disease spot dried up and showed gray, the edge was brown, and the epidermis was ruptured. Due to the destruction of the transporting tissue in the stem, affecting the transport of nutrients, the leaves began to turn yellow, wither and fall off gradually from the bottom up, resulting in the death of the whole plant. This disease is the most serious after the florescence. When the disk is damaged, there are water-immersed spots on the back, and the receptacle is brown and softened. In case of rainy weather, the disease spot expands rapidly, which can penetrate the disk, turn from the back to the front, and grow a kind of white hyphae, which causes the disk to rot, so that the grain can not mature, and in serious cases, it can cause kernel rot or grain self-shedding. Sunflower Sclerotinia sclerotiorum prevention and control methods: first, the use of physical control method to find diseased plants, to immediately pull out and destroy, in order to prevent spread. Sclerotia can survive in the soil for several years, and generally lose most of its vitality after 3 years. The rotation of sunflower and Gramineae crops can reduce the disease. The longer the rotation time, the better the effect, not with legumes, cruciferous and other crops. 2. Use chemical control method 1. Spray the lower part of the plant and the back of the disk once or twice before the sunflower budding or in the full flowering stage with 40% Wankuli 800 × 1000 times liquid. 2. Spray 1000 times of 50% tophan wettable powder before budding or in full bloom of sunflower. 3. The control effect can reach more than 80% by spraying 50% Sukeling 500 × 1000 times liquid at the seedling stage or flowering stage. 4. When the temperature reaches 1820 ℃, the water content of the surface soil is more than 11%, and the ascomycete begins to be unearthed, it is the best time to sprinkle pesticide on the ground. 70% pentachloronitrobenzene 30kg per hectare, moist fine soil 150kg 225kg, mixed evenly in the field, can inhibit sclerotia germination and kill budding young bud tubes, the inhibition rate can reach 91.3%, and the control effect can reach more than 78.5%. Third, the prevention and control of drip irrigation 1, the use of drip irrigation to control water. Drip irrigation under plastic film was used to adjust water supply to avoid low-lying water accumulation and control field humidity so as to reduce the occurrence of Sclerotinia sclerotiorum in sunflower. 2. Use drip irrigation to fertilize with water. Drip irrigation under plastic film can improve the disease resistance of crops, and can also achieve timely and appropriate amount, which can save about 20% of fertilizer. Drip irrigation under plastic film saves water by 50%, reduces deep leakage, and can better prevent soil secondary salinization. Drip irrigation with water fertilization, pesticide application, not only save chemical fertilizers and pesticides, but also reduce the pollution to the soil and environment. Click to get more sunflower planting techniques click to get more food crop planting techniques