Ring spot:
Symptoms:
Small, purple spots surrounded by a ring of water-soaked tissue on leaves which mature to brown spots with olive green borders 1-2 cm across; spots may develop numerous fruiting bodies which give them a black appearance or develop a concentric pattern; heavily infected leaves may dry up and curl inwards.
Management:
Refrain from planting in areas known to have had disease previously; rotate crop to non-brassicas; sanitize tools and equipment regularly; apply appropriate fungicide if disease is identified in crop.
Bacterial soft rot:
Symptoms:
Water-soaked lesions on leaves and flower heads which expand to form a large rotted mass; surface of lesions usually crack and exude slimy liquid which turns tan, dark brown or black on exposure to air.
Management:
Chemical treatments are not available for bacterial soft rot, control relies on cultural practices; rotate crops; plant in well-draining soils or raised beds; only harvest heads when they are dry; avoid damaging heads during harvest.
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