Detailed Introduction to the Symptoms of Grape Brown Spot Disease
Symptom identification: This is a fungal disease that mainly affects leaves. It is divided into large-spot lesions and small-spot lesions, caused by two different pathogens. Large brown spot disease initially forms circular or polygonal lesions around the leaf veins. The lesions are brown to dark brown with red-brown edges, and a yellow-green halo surrounds the lesions. They gradually expand to form brown...
Symptom identification: This is a fungal disease that mainly affects leaves. It is divided into large-spot lesions and small-spot lesions, caused by two different pathogens. Large brown spot disease initially forms circular or polygonal lesions around the leaf veins. The lesions are brown to dark brown with red-brown edges, and a yellow-green halo surrounds the lesions. They gradually expand to form concentric rings of varying shades of brown. When humidity is high, dark brown mold clusters are scattered on the surface or underside of the lesions. Several lesions may merge to form large spots, and in the later stages the diseased tissue cracks and dries up. Small-spot lesions are relatively similar in size, dark brown in color, and in the later stages a brown mold layer develops on the underside of the lesions.