Common Diseases of Peonies - Brown Spot Disease

Common Diseases of Peonies - Brown Spot Disease

Brown spot disease

Symptoms: Brown spot disease mainly harms the leaves of peonies, and also infects branches, flower organs, seeds, and other parts. At the beginning of the disease, large, nearly circular or irregular spots appear on the leaf blades, and both sides of the lesion are brown in color; When seriously ill, the convergence of disease spots causes leaf blight and distortion, and under humid conditions, a dark green mold layer grows on the back of the disease spots.

Condition of onset: Warm and rainy weather, severe onset; Multiple pathogens, biased application of nitrogen fertilizer, high planting density, and poor ventilation and light transmission are more likely to cause the occurrence of diseases.

Prevention and control methods:

Reduce the source of infection and thoroughly remove the diseased remains on the ground in autumn; Spray 50% carbendazim 600 times solution or 3 degrees of stone sulfur mixture before the early spring plants sprout to kill the bacteria on the plants.

Spray 50% carbendazim 1000 fold solution or 65% mancozeb 500-600 fold solution once every 7-10 days after onset, continuously spraying 3-4 times.

Strengthen cultivation management, moderate planting density, and apply organic and compound fertilizers.