Detailed Explanation of Control Methods for Two Major Diseases of Codonopsis pilosula

Root rot and rust are the two most common major diseases in Codonopsis pilosula cultivation, and these two major diseases have seriously affected the cultivation benefits of Codonopsis pilosula. So how should these two major diseases be controlled respectively?

Codonopsis pilosula root rot:

Symptoms of Codonopsis pilosula root rot: It often begins to occur during the high-temperature and high-humidity period from May to June in summer. It mainly occurs in Codonopsis pilosula plants that have been growing for more than 2 years. In the early stage of the disease, the lateral roots and fibrous roots near the ground turn blackish brown. When there is a lot of rain and the disease is severe, the root system rots and the plants die, seriously affecting yield.

Control methods for Codonopsis pilosula root rot: 1. Drain water promptly during high-temperature and rainy seasons to prevent waterlogging in the field. 2. Remove diseased plants promptly when found, and disinfect the diseased holes with 5% lime milk to prevent spread. 3. When the affected area is relatively large, irrigate the diseased area with a 500-fold dilution of 50% carbendazim. 4. During land preparation, use 1 kg of 70% quintozene powder per mu for soil disinfection. 5. In the early stage of the disease, spray or drench the roots with a 2000-fold dilution of 50% thiophanate-methyl, once every 7-10 days, for 2-3 consecutive times. 6. Implement crop rotation with crops of different families and genera, such as soybean, wheat, and corn.

Codonopsis pilosula rust

Symptoms of Codonopsis pilosula rust: It occurs from July to August every year and mainly damages leaves and stems. The back of diseased leaves bulges and shows yellow spots, which later rupture and release orange-yellow powder. After the disease occurs, the leaves dry up or fall early. When the disease is severe, the yield of Codonopsis pilosula roots decreases considerably.

Control methods for Codonopsis pilosula rust: 1. After the plants wither in winter, clean the garden and burn the diseased and residual plants. 2. In the early stage of the disease, spray a 200-fold dilution of 50% dinitrodisperse or a 400-fold dilution of 97% sodium diethyldithiocarbamate, once every 7-10 days, for 2-3 consecutive times, or spray a 1000-1500-fold dilution of 25% triadimefon for control. 3. Set up supports in time, change ventilation conditions, and reduce field temperature.