Detailed Explanation of the Causes of Onion Bulb Rot and the Prevention and Control Methods
Onion, also known as scallion bulb, originated in the West Asia region, and is now planted and cultivated in all regions of our country, with a relatively huge market demand and remarkable economic benefits, and nowadays it has attracted many farmers to plant it. However, many problems are encountered during planting that affect the yield and marketability, and onion bulb rot is one of them. Below, Qinnong Web brings you the causes of onion bulb rot and the prevention and control methods. Let's learn about them together.
1. Rot caused by diseases
During onion planting, it will suffer from the invasion of various diseases, which harm the normal growth and development of onions, and in severe cases cause a large number of plant deaths. There are many diseases that cause onion bulb rot, such as onion dry rot, onion dry rot, onion bulb rot disease, onion black aspergillus disease, onion black aspergillus disease. The characteristics of these diseases when they break out are different, but in the later stage of the disease they will all cause onion bulbs to rot.
Prevention and control methods: Attention must be paid to the prevention and control of diseases. Before planting, disinfect the soil and seeds to eliminate the pathogens in the soil and carried by the seeds. During planting, strengthen fertilizer and water management, increase the application of phosphorus and potassium fertilizers, and improve disease resistance. When some diseased plants are found, remove them and take them out of the field, disinfect the diseased holes, and then spray the corresponding agents for prevention and control.
2. Rot caused by physiological diseases
The so-called physiological diseases refer to some diseases caused by improper management during onion planting. For example, when onions lack calcium substances, it will cause onion bulb rot; when onions sprout during storage, it causes nutrients to be consumed in large amounts, making the bulbs soft and hollow and causing rot; in the late stage of onion bulb growth, yellowing of leaves and leaf tips occurs, resulting in no new leaves to supplement the leaf sheaths and causing hollowness, which makes the leaf sheaths loose. When watering or raining, water flows into the bulbs, causing bacterial infection and rot; in addition, mechanical damage caused by some reason during planting, harvesting, and storage will also lead to pathogen infection and rot; there is also unsuitable storage environment, with relatively high temperature and humidity, which makes onions sprout and take root, causing rot.
Prevention and control methods: According to each cause of rot, “prescribe the right medicine” for prevention and control. For example, if there is calcium deficiency, supplement calcium in time. When fertilizing, apply organic fertilizer appropriately to ensure the supply of trace elements. It is best to manage planting, harvesting, and storage well to avoid rot caused by the above reasons.
3. Rot caused by insect pests
The main insect pests that cause onion bulb rot are onion maggots or root maggots. They are common insect pests during onion planting, mainly causing damage underground as larvae, gnawing on the bulbs, causing onions to be unable to grow normally, and in severe cases the leaves wither, turn yellow, and rot.
Prevention and control methods: Use a combination of agricultural control and chemical control. Do not use chemical control unless absolutely necessary. Before overwintering, completely remove the weeds and residues in the field to prevent adults from laying eggs, or prepare trapping and killing agents and attract egg laying. Natural enemies can also be used for control. During the outbreak period of insect pests, chemical control can be used, but attention should be paid to the concentration and dosage of the chemicals to avoid phytotoxicity to onions.
The above are the causes of onion bulb rot and the prevention and control methods brought to you by Qinnong Web. We hope they can help you. To learn more about onion planting knowledge, please stay tuned to Qinnong Web.