Symptom

• Yellowing and browning of cotyledons followed by browning on the petiole.
• Loss of turgidity, yellowing, drooping and wilting of leaves.
• Browning or blackening of vascular tissues.
• Infected plants appear stunted with fewer bolls.

• Survive in soil as saprophyte for many years and chlamydospores act as resting spores.
• Primary spread is through seed, dormant hyphae and chlamydospores.
• The pathogen is externally and internally seed-borne.
• Secondary spread by wind and irrigation water.

• Soil temperature of 20-30 0 C .
• Hot and dry periods followed by rains .
• Heavy black soils with an alkaline reaction
• Increased dose of nitrogen and phosphatic fertilizers .
• Wounds caused by nematode (Meloidogyne incognita) and grubs of Ash weevil (Myllocerus pustulatus)

• Remove and burn the infected plant debris in the soil after deep summer ploughing. .
• Apply farm yard manure or other organic manures @ 4 t/ac. .
• Follow mixed cropping with non-host plants to reduce the soil temperature below 200C by providing shade.
• Treat the acid-delinted seeds with Chlorothalonil at 4 g/kg of seed .
• Seed treatment with Bacillus subtilis (10g/kg) or Trichoderma asperellum @ 4 g/kg.
• Apply Trichoderma asperellum @ 1 kg/ acre, twice in the soil during sowing and 90 DAS . Multiply 1 kg of T. asperellum in 100 kg of Farm yard manure for 15 days before application.
• Spot drenching with Carbendazim 50%WP @1g/ lit of water

• Online resources
• CPG 2020

Vascular browning

Yellowing of leaves