How do onions rot in summer?

How do onions rot in summer? Please introduce that summer onion rot is mainly caused by the following factors: first, the common diseases of rotten onions caused by diseases are soft rot (bacterial disease) and stem rot (fungal disease). The prevention and control methods are as follows: 1. Pay attention to crop rotation, avoid repeated stubble with onion and garlic crops. The cultivated land should be ploughed as deep as 30 cm as far as possible. if rotary ploughing is used, no-deep ploughing should be sprayed before planting. For about 20 days, the soil of 50 cm deep is loose and transparent, which is beneficial to the growth and development of roots and improve the disease resistance of plants. two。 Apply mature fertilizer to prevent fertilizer from carrying bacteria. 3. Try to make use of ridge farming. 4. During the growing period, the application amount of nitrogen fertilizer should be controlled, and fertilization should be combined with nitrogen, phosphorus and potassium. 5. Pay attention to timely drainage during bulb formation to avoid long-term stagnant water. 6. Timely control of insect pests to avoid causing wounds. 7. Before the onset of the disease, the following agents were used: 72% agricultural streptomycin 4000 times solution, 50% copper succinate wettable powder solution and 72% Kelu wettable powder solution 8000 times alternately. Second, the wounds caused by underground pests such as rotting ground tiger, golden needle worm and maggot caused by insect pests can easily cause mold to invade and cause infectious diseases at the same time. In addition to drug control, Wanling, hit and other chemicals should be sprayed in the ground in early June to control the harm of adults. Third, the decay caused by element deficiency due to the low soil temperature in early spring and the excessive accumulation of ammonium nitrogen in the soil, affecting the absorption of calcium, potassium, magnesium and other elements, resulting in the occurrence of physiological diseases lacking the above-mentioned fertilizer elements. Excessive application of nitrogen fertilizer during the growing period will also lead to the lack of the above elements. Due to the lack of the above elements, the leaves along the green, leaf tip withered, at the same time, the outer and internal scales of the bulb will also dry up and rot. Therefore, attention should be paid to the combined application of nitrogen, phosphorus and potassium in cultivation. During the growing period, high-energy red potassium and 0.2% calcium nitrate solution can be applied to the root to supplement potassium and calcium. 4. The leaf sheath of rotten onion caused by Rain Water and stagnant water is loose and the gap is large in the later stage of growth. Excessive stagnant water in the field will be immersed into the leaf sheath of lodging plants; Rain Water will be immersed into the leaf sheaths of unlodged plants. All the above factors will cause the bulb to rot. For this reason, attention should be paid to drainage and early harvest. Click to get more onion planting techniques click to get more vegetable planting techniques