Brassica rapa, commonly known as oilseed rape, is a popular vegetable with a smooth and tender texture, making it delicious both raw and after secondary processing. Here, we introduce the symptoms and control methods of clubroot disease in Brassica rapa:
Symptoms of Clubroot Disease in Brassica Rapa
In the early stages of infection, water-soaked lesions appear at the base of the plant stem. As the disease progresses, the lesions expand, turn brown, and the stem base becomes soft or longitudinally cracked. In high humidity, dense cotton-like white mycelium grows on the surface of the lesions, eventually forming white clubroot. Further development results in the formation of black granular clubroot resembling mouse droppings. Ultimately, the infected plants wilt and die.
Control Methods for Clubroot Disease
-
Use Resistant Varieties: Choose Brassica rapa varieties resistant to clubroot disease. Before sowing, treat seeds with seed dressing agents or float seeds in 10% saline solution 2-3 times to effectively reduce seed contamination.
-
Practice Crop Rotation: Rotate Brassica rapa with other vegetables such as tomatoes and cucumbers. Ensure thorough land preparation and remove crop residues from the field.
-
Select Suitable Land: Choose elevated, well-drained, deep, and sandy loam soil with a pH of 7-8 for planting.
-
Apply Fertilizers Reasonably: Apply plenty of well-rotted organic fertilizer, use nitrogen fertilizer appropriately, increase phosphorus and potassium fertilizer, promote vigorous growth of Brassica rapa, and improve plant resistance to diseases.
-
Field Management: Cultivate and cultivate the soil in a timely manner to cultivate strong seedlings. Properly dense planting and increase field ventilation and light transmission. Water and ventilate in time, control watering before growth and after disease, water in the morning on sunny days, ventilate to remove moisture, and spray pesticides timely after continuous rainy weather.
-
Chemical Control: After the onset of the disease, spray with 50% methyl thiophanate 500 times liquid, 90% carbendazim 800 times liquid + 750 times liquid vigor agent, 50% tricyclazole wettable powder 1000 times liquid, etc., once a week, for 2-3 consecutive times. In severe cases, spray every 3-5 days.
Above are the symptoms and control methods of clubroot disease in Brassica rapa. To improve the quality and yield of Brassica rapa, it is essential to implement effective disease control measures.
