Symptom
- Small, pale to brown, irregular or round spots, appear on the leaves.
- Each spot has a central lesion surrounded by concentric rings.
- Several spots coalesce together to form blighted areas.
- The affected leaves become brittle and fall off.
- The spots also appear on bracts and bolls.
Survival and Mode of Spread
- The pathogen survives in the infected crop debris as dormant mycelium.
- Primary spread is through infected crop debris.
- Secondary spread is through air-borne conidia.
Favourable Conditions
- High humidity, intermittent rains and moderate temperature of 25-28 0C.
Management
- Remove and destroy the infected plant residues.
- Perform deep ploughing during summer.
- Avoid seeds from infected crop.
- Spray Copper oxychloride @ 500 g or Chlorothalonil @ 200 g or Difenaconazole @ 100 ml or Kresoxim methyl @ 200 ml or Tebuconazole @ 200 ml or Trifloxystrobin + Tebuconazole @ 120g or Propiconazole @ 100 ml or Metiram 55% + Pyraclostrobin 5% WG @ 100 g or Fluxapyroxad 167 g/l + Pyraclostrobin 333 g/l SC @ 150 g or Pyraclostrobin 20% WG @ 100g or Propineb 70% WP @ 500g per acre at 60, 90 and 120 days after sowing.
- Apply Bacillus subtilis (BSC5) @ 400 g/ac on 60, 90 and 120 days after sowing.
Source of information
- Online resources
- CPG 2020
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Irregular Necrotic Brown Spots |
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Boll Infection |
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