CR – Clubroot
Scientific Name: Plasmodiophora brassicae
Type: Fungus
Clubroot is a world-wide fungal soil-borne disease that affects the growth of cabbage, cauliflower, broccoli, Brussels sprouts, kohlrabi, radishes, rutabaga, tomatoes, and turnips. This disease can cause severe crop yields and total crop loss. The fungus infects the plant through root hairs or wounds. Symptoms include wilting and yellowing of leaves. Young plants are stunted and may die. The roots are usually swollen and distorted (clubbed). The disease is spread by farm equipment, wind, and water. The infected plants should be removed and burned to avoid further infestation. The disease is favorable when temperatures are 54-81 F and usually occur when soil is moist. The disease is primarily associated with acid soils. Plan on using a 7 year crop rotation and avoid planting in the same location, year after year, as the disease can survive in the soil up to 20 years. Use proper weed control techniques. Proper tillage practices may be helpful in managing the disease. It is essential that hydrated lime be added each year to the soil unless the soil pH exceeds 7.5. Thoroughly clean equipment after working in a field. Plant crops in well drained soil. The best option is to use disease resistant varieties.