Introduction

Moong or green gram and urad or black gram are important pulse crops in India. They improve soil fertility through nitrogen fixation and fit well in kharif, summer, and intercropping systems. However, during kharif, high humidity and repeated rainfall increase the risk of leaf spot diseases.

Leaf spot reduces green leaf area, weakens photosynthesis, causes premature leaf fall, and affects flowering and pod formation. Disease severity and yield loss depend on variety, weather, crop stage, and management timing.

Types of Leaf Spot in Moong and Urad

Farmers may see different kinds of spots on leaves. Correct identification helps in better management.

Cercospora Leaf Spot

• Small brown to grey spots
• Spots may have dark margins
• Starts mostly on lower leaves
• Leaves may turn yellow and fall early

Alternaria Leaf Spot

• Brown spots with concentric rings
• Target-board appearance
• More common during humid weather
• Can spread quickly in dense crop

Bacterial Leaf Spot

• Water-soaked spots in early stage
• Spots later turn brown
• May spread after splashing rain
• Fungicides will not control bacterial disease effectively

Other Leaf Blight or Spot Complexes

• Irregular brown patches
• Rapid yellowing and drying
• Often seen under continuous wet weather

Conditions That Favour Leaf Spot

Leaf spot increases when:

• Humidity remains high
• Rainfall is frequent
• Crop spacing is narrow
• Field drainage is poor
• Infected crop residue remains in the field
• Susceptible varieties are grown
• Crop rotation is not followed
• Sprays are delayed until severe infection

6 Fungicide Options for Leaf Spot Management in Moong and Urad

Use only fungicides registered for the crop and target disease as per the approved label. Do not use any chemical only because it is common in the market.

 

Sr. No.	Fungicide Technical Name	Type	Use Situation
1	Mancozeb 75% WP	Contact fungicide	Preventive protection against fungal leaf spots
2	Carbendazim 50% WP	Systemic fungicide	Label-based use for fungal diseases
3	Hexaconazole 5% SC	Systemic fungicide	Label-based use for foliar fungal diseases
4	Propiconazole 25% EC	Systemic fungicide	Label-based use only if approved for crop and disease
5	Carbendazim 12% + Mancozeb 63% WP	Combination fungicide	Broad fungal leaf spot management where label permits
6	Azoxystrobin formulation	Strobilurin fungicide	Label-based foliar disease management

 

Right Spray Time and Method

Spray Timing

• Start field scouting from 20–25 days after sowing.
• Spray when early fungal spots appear and weather is favourable.
• Protect the crop before flowering if disease pressure is building.
• Repeat spray only if disease continues and the label allows.
• Avoid spraying during rain, strong wind, or hot afternoon.

Final Thoughts

Leaf spot in moong and urad should be managed early. Farmers should first identify whether the disease is fungal or bacterial, then use the correct approved fungicide if needed.

Good seed, proper spacing, drainage, crop rotation, and early scouting are equally important for saving yield.