Control Methods and Key Technical Points for Codonopsis Diseases

I. Rust mainly damages the stems and leaves of Codonopsis. Control methods: clean the field, eliminate field weeds and diseased plants. In the early stage of the disease, spray 25% triadimefon wettable powder at 1000-1500 times dilution, or 90% dithianon sodium at 400 times dilution for control. Spray once every 7-10 days, for 2-3 consecutive sprays.

II. Root rot mainly damages the roots of Codonopsis. Control methods: from July to August, apply additional phosphorus and potassium fertilizer. Before transplanting Codonopsis, soak the roots in 50% thiophanate-methyl wettable powder at 1000 times dilution for 5 minutes. When the disease occurs, drench the roots with 50% thiophanate-methyl wettable powder at 700 times dilution, or 58% metalaxyl-mancozeb at 600 times dilution, once every 7 days, for 2-3 consecutive drenchings. In plots with a relatively high disease incidence, drench the roots with 70% thiophanate-methyl at 1000-1500 times dilution, and remove the diseased plants.