What is radish "black heart"?

What is radish "black heart"? Radish black heart is caused by what? Is there any way to prevent and cure it? Also ask netizens to help guide and introduce radish black rot, commonly known as black heart, rotten heart, the disease is a disease caused by bacteria, farming network sorted out the harm of radish black rot and its causes and control methods, listed below for netizens' reference. The harm of radish black rot: the disease harms the leaves and roots of radish. In the seedling stage, the diseased cotyledons were flooded, and the root pulp blackened and rotted. Leaf disease, yellow spots appeared in many places on the leaf edge, and then showed V-shaped disease spots, leaf veins blackened and reticulated, leaf margin turned yellow, and the whole leaf became yellow and withered after expansion. The pathogen of radish black rot develops along the veins and vascular bundles to the roots. Root disease, duct blackening, internal tissue dry rot, the appearance of often do not see obvious symptoms, but the pulp is mostly black dry rot, and finally form a cavity. The disease does not smell when it decays and can be distinguished from soft rot. But sometimes the field can be complicated with soft rot, showing the form of rot. Cause of radish black rot: the suitable temperature for radish black rot is 25 ℃ ~ 30 ℃. The disease is serious in high temperature and rain, continuous cropping or early sowing, low-lying terrain, excessive irrigation, poor drainage, little or unripe fertilizer, and man-made wounds and insect injuries. in rainy years, the disease is serious, and in severe cases, the plant rate can reach 100%, and the mortality rate is more than 30%, resulting in greater losses in yield and quality. Caused by sowing infected seeds, the buds can be infected in the soil, so that the seedlings can not be unearthed, although some can be unearthed, but die soon after emergence. It spreads in the field through wounds caused by irrigation water, Rain Water, insect injuries and agricultural operations. Control methods of radish black rot: method one, select disease-tolerant varieties, such as Fengguang first generation radish, Shijiazhuang white radish and so on. Method 2. Sowing at the right time should not be premature. Sowing late in a suitable sowing time can reduce the occurrence of diseases. Strengthen cultivation management, squat seedlings at the right time, watering small water frequently at seedling stage, reduce soil temperature, and set seedlings in time. Avoid excessive drought or waterlogging. Rotation stubble, using formula fertilization technology. Method 3. To disinfect the seeds before sowing, the seeds can be treated with 0.2% 50% thiram wettable powder or 35% metalaxyl, or soaked in 50 ℃ warm water for 25 minutes, then immediately transferred to cold water for cooling, dried and sowed, or 60 ℃ dry heat sterilization for 6 hours, or sowed with streptomycin 1000 times solution. Method 4. The soil can be treated in the continuous diseased field. Before sowing, use 750 grams of 50% Fumishuang wettable powder per mu, 10 kg of water, mix in 100 kg fine soil and sprinkle it into the sowing hole. Method 5. In the early stage of black rot disease, the central diseased plant was removed in time, and 50%DT500 double solution mixed with agricultural streptomycin 2000-fold solution was sprayed, or 77% or 72% agricultural streptomycin sulfate wettable powder 4000-fold solution was sprayed once every 7 to 10 days for 2 times in a row. Click for more radish planting techniques click to get more vegetable planting techniques