Symptoms of rice blast disease:
- Leaf spots turn spindle-shaped with a light-brown or grayish center and a dark-brown border.
- Spots on leaves, stems, and panicles can cause premature death.
- Severe cases lead to extensive crop damage, reduced grain quality, and lower yields.
- Disease spreads rapidly in warm, humid conditions.
- High disease pressure occurs during flowering and grain-filling stages.
Management of rice blast disease:
- Use resistant or tolerant rice varieties.
- Practice crop rotation and avoid planting rice in the same field year after year.
- Apply fungicides preventively during high disease pressure.
- Maintain proper soil fertility and irrigation practices to reduce plant stress.
Brown spot
Brown spot of paddy, also known as Helminthosporium leaf spot, is a fungal disease that affects rice crops.
The five major symptoms of brown spot of paddy are:
- Small, oval-shaped lesions on the leaves.
- Lesions turn brown and have a yellow halo around them.
- Lesions may coalesce and cause large areas of the leaf to turn brown.
- Infected leaves may wither and die prematurely.
The two major management strategies for brown spot of paddy are:
- Cultural management: This involves practices such as crop rotation, planting resistant varieties, avoiding overhead irrigation, and timely harvesting to reduce the severity of the disease.
- Chemical management: Fungicides such as Propiconazole, Tricyclazole, and Tebuconazole can be applied to control the disease.
Bunt
Bunt of paddy, also known as stinking smut, is a fungal disease that affects rice crops. The five major symptoms of bunt of paddy are:
- Infected seeds look healthy but contain black powdery spores.
- Affected plants are stunted and have yellowish leaves.
- Diseased plants have fewer and smaller panicles.
- Infected panicles have empty or partially filled grains.
- A strong foul smell is produced due to the presence of the fungus.
The two major management strategies for bunt of paddy are:
- Cultural management: This involves practices such as planting certified disease-free seeds, avoiding water-logging, using balanced fertilization, and crop rotation to reduce the severity of the disease.
- Chemical management: Fungicides such as Carbendazim, Thiram, and Propiconazole can be applied to control the disease.
False smut
False smut of paddy, also known as Ustilaginoidea virens, is a fungal disease that affects rice crops.
The five major symptoms of false smut of paddy are:
- Infected panicles become distorted and turn greenish-white.
- The infected panicles are filled with powdery spores.
- Diseased panicles are heavier and larger than healthy panicles.
- The grains of infected panicles turn into dark brown masses.
- Infected panicles have a strong fishy odor.
The two major management strategies for false smut of paddy are:
- Cultural management: This involves practices such as avoiding excess nitrogen fertilizer, maintaining proper drainage, and avoiding water-logging to reduce the severity of the disease.
- Chemical management: Fungicides such as Tebuconazole, Tricyclazole, and Propiconazole can be applied to control the disease.