The cabbage downy mildew harms the leaves. At the beginning of the disease, chlorotic spots appear on the leaves. After expansion, the leaves are limited by the veins to produce polygonal or irregular shaped lesions. The lesion size is 5 to 10 mm or more, yellow or light yellowish brown. Slightly sunken. When wet, a white mold layer develops on the back of the lesion. When the disease is severe, the lesions on the leaves are contiguous, resulting in dead leaves.
The control method for downy mildew of Brassica oleracea is as follows: 50% dimethomorpholine 1500 or 800 mg or 75% chlorothalonil 500mg, 5 to 7 times can be used for effective control.
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