What are the latest control methods for fennel sclerotinia rot
Fennel is a common leafy vegetable crop, and sclerotinia rot is a common disease during cultivation. If not controlled in time, it will cause severe yield reduction in fennel. So how should fennel sclerotinia rot be controlled? Let us learn about it together.
1. Disease symptoms
Fennel sclerotinia rot mainly damages the leaf stalks and stems near the ground. The affected parts often develop brown, water-soaked, irregular lesions, and later the diseased parts gradually become wet and rotted. Tissues above the diseased parts often wilt, and in severe cases the aboveground parts die because they lack nutrients and water. In humid environments, the diseased parts produce large amounts of white mycelium, which later twists together into black sclerotia.
2. Occurrence pattern
Sclerotinia rot is a fungal disease. The pathogen mainly overwinters as sclerotia in the soil or mixed with seeds, and when conditions are suitable the following year, ascospores spread through wind and rain. The time of onset differs among different regions. It is highly prone to occur in plots with continuous cropping, heavy clay soil, low-lying terrain, and poor drainage that easily accumulates water; in addition, excessive planting density and poor field ventilation can also induce this disease; uneven fertilizer and water application, which causes plants to grow leggy, overly vigorously, or too weakly with low disease resistance, can also give this disease an opportunity; in early spring, low temperatures, long periods of continuous cloudy and rainy weather, and long-term excessive humidity inside protected cultivation areas lead to more severe disease.
3. Control methods
Rotate with non-Apiaceae vegetables for 2—3 years. If conditions permit, paddy-upland rotation can be carried out. When planting, choose as much as possible flat land that is not prone to water accumulation for cultivation. Fertilizer and water management should be strengthened appropriately to promote healthy growth and enhance disease resistance. Wind protection and moisture removal should be carried out in a timely manner. During low-temperature seasons, water as little as possible during cultivation to avoid flood irrigation. When diseased plants are found, remove them promptly and take them out of the field, then spray the corresponding pesticide for control. After harvest, promptly deep plow, or flood with water to soak, or close the greenhouse for 7—10 days, using high temperature to kill sclerotia in the surface layer, or disinfect the seeds before sowing.
The above is an introduction to control methods for fennel sclerotinia rot. We hope it can help you. To learn more related knowledge, please keep following us.