What is the cause of death of Atractylodes macrocephala? Come on, everybody, 3Q.

Stem rot and root rot of Atractylodes macrocephala, commonly known as dead seedlings and rotten roots, are also called root rot. In recent two years, it has shown an upward trend, which can cause a large number of dead seedlings in severe cases, which is the biggest disease of Atractylodes macrocephala at present. People really want to cry. After the seedlings of Atractylodes macrocephala were unearthed, they began to wither and die one after another, especially after rain and strong light. When Atractylodes macrocephala seedlings are pulled up, the stem base turns black and thin, and the inside of the root bark is cut off, which is purplish red in the early stage and decays or shrinks in the late stage. As long as the root bark is red, it proves that the disease has reached the middle and late stage, and it can't be cured even with drugs, which is why we still have dead seedlings within 7 days after taking drugs. When the humidity is high, a sparse layer of white mold grows in decay, which is the mycelium and conidia of pathogenic bacteria. The fungus belongs to saprophytic Fusarium. Pathogenic mechanism: the pathogen overwinters in the soil or on diseased plants, and the spore of the pathogen can survive in the soil for 5- 10 years. Pathogens are usually caused by the invasion of the stem base and root wounds of cluster buds. After the disease occurs, conidia multiply in the affected area, spread through rain or water, spread and infect neighboring healthy plants, and make the disease recur (this is the reason for a dead end). The degree of the disease is related to the soil moisture content and the bacteria-carrying situation. Due to uneven soil preparation, water accumulation in the field or premature watering at seedling stage, rain after watering, or continuous rainy days, the soil is sticky and airtight, which will cause serious diseases. In addition, the last crop is cotton, eggplant, pepper and other crops susceptible to the disease, or the seeds are infected with germs, and the disease is serious when the crops are repeatedly replanted. Prevention and control of misuse: 1: crop rotation, crop rotation of Gramineae (wheat, corn), Cruciferae (Chinese cabbage, radish, rape), etc. 2. Choose fields with high drought degree and good irrigation and drainage, carefully prepare the soil, increase the application of phosphorus and potassium fertilizer, and control underground pests. The soil conditioner with national patent products is exempt from deep ploughing, and has been rated as a key new product by four national ministries and commissions. It is the only high-tech soil conditioner approved and registered by the Ministry of Agriculture in China. If the soil is not deeply ploughed, it can break the soil hardening from top to bottom, loosen the soil, scientifically and evenly adjust the water, fertilizer, gas and heat in the soil, develop the root system of crops, and effectively improve the utilization rate of fertilizer. Because the soil is loose and breathable, it increases the number of beneficial microorganisms in the soil, thus inhibiting the reproduction of harmful bacteria, thus effectively reducing the occurrence of soil-borne diseases. In the later stage, the soil was loose and breathable, and the root system was developed, which improved the utilization rate of fertilizer and accelerated the expansion of Atractylodes macrocephala. It is no exaggeration to harvest 200-300 Jin of Atractylodes macrocephala per mu. No-tillage is suitable for all kinds of soils and crops, and can achieve the purpose of increasing production and income. Because of these advantages, it has been praised and supported by the media and experts and professors from all walks of life. 3. Disinfect seeds and seedlings before sowing. When buying Atractylodes macrocephala sprouts, cut them vertically with a blade to see if they are moldy or infected (red or black). Disinfection of soil: 2-4 kg of "Nonghui Lincheng" brand multifunctional microbial inoculum and 40% phoxim 1-2 kg are used to dry fine soil or spread cake fertilizer during soil preparation, which can effectively prevent the occurrence of this disease. Chemical prevention and treatment: use 0.5% "Taikang" (microbial chitosan) 300-500 times before or at the beginning of the disease; 2% benazinphos (propamidine) is 600-900 times; Adding the above chemicals and soil conditioners can avoid using one bottle of aqua or powder per mu to irrigate the roots deeply, which can not only loosen the soil, increase the air permeability of the soil, but also promote the penetration of liquid medicine and improve the control effect. In addition, due to the loose soil and developed roots, the fertilizer utilization rate of Atractylodes macrocephala during the expansion period was improved, which accelerated the expansion of Atractylodes macrocephala and increased the yield by more than 15%. (For those who have been subjected to no-tillage during the land preparation, only the roots can be irrigated without no-tillage; for those who have not been subjected to no-tillage during the land preparation, no-tillage should be added at the first time, and then only fungicides should be used). When irrigating roots, each plant should be irrigated with about 3 liang of chemical solution, and each mu should be irrigated with chemical solution 10-20 barrels, and the roots should be irrigated 1-3 times as appropriate, with a general interval of 7. Prevent bacteria from multiplying in large numbers after rain, leading to disease outbreaks. The combination of foliar disease prevention and insect control and "Nongwilling patent medicine" (disease-resistant type) 300 times can improve plant photosynthesis, promote the rapid healing of Atractylodes macrocephala root and rotten root wounds, improve disease resistance, promote expansion and increase yield.