Bitter gourd, a common vegetable grown in many regions, is susceptible to various diseases during cultivation. Many growers are unfamiliar with bitter gourd leaf browning. Let's explore what this disease is all about.
Symptoms of Bitter Gourd Leaf Browning
Bitter gourd leaf browning, also known as leaf blight, primarily affects the leaves. In the early stages, the leaves develop small round brown spots, which later enlarge and merge, leading to leaf drying.
Causes of Bitter Gourd Leaf Blight
Bitter gourd leaf blight is closely related to temperature and humidity during the growth period. It occurs when the temperature ranges from 14 to 36°C with a relative humidity of over 80%. Excessive rainfall and high humidity above 90% increase the likelihood of disease. Factors such as continuous cropping, excessive nitrogen fertilization, and poor field drainage contribute to the severity of the disease.
Prevention and Control Methods
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Rotate Crops: Use disease-free bitter gourd seeds and practice crop rotation.
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Fertilization Management: Apply compost or well-rotted organic fertilizer supplemented with foliar nutrients to enhance disease resistance. Increase the application of phosphorus and potassium fertilizers while avoiding excessive nitrogen fertilization.
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Fumigation: Use 5% carbendazim powder or ignite 45% carbendazim smoke agent in the evening after bitter gourd leaf blight occurs. Repeat fumigation every 7-8 days for two times.
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Chemical Control: Use targeted fungicides such as 75% carbendazim wettable powder or 70% mancozeb wettable powder, mixed with a new high-fat film. Avoid spraying within 4 hours before rain and stop spraying 7 days before harvest.
Bitter gourd leaf browning is a common disease that affects bitter gourd cultivation. Proper preventive measures and management are essential to control its spread effectively.
