Fungal pathogens involved in boll rot are Fusarium moniliforme, Colletotrichum capsici, Aspergillus flavus, Aspergillus niger, Rhizopus nigricans, Nematosporanagpuriand Botryodiplodia sp.

Symptom

• Disease appears as small brown or black dots which later enlarge to cover the entire bolls.
• Infection spreads to inner tissues and rotting of seeds and lint occur.
• The bolls never burst open and fall off prematurely.
• Fruiting bodies of fungi are observed on the bolls .

• The fungi survive on the infected bolls in the soil.
• Primary spread is through infected bolls.
• Secondary spread is through air-borne conidia.

• Heavy rainfall during the square and boll formation stage .
• Punctures caused by the insects
• Closer spacing
• Excessive nitrogen application.

• Adopt optimum spacing.
• Apply the recommended doses of fertilizers.
• Spray Copper oxy chloride @1000 g/acre or Carbendazim @ 200 g /acre or Mancozeb @ 800 g / acre.

• Online resources
• CPG 2020

Boll Brown spot

Lint staining

Boll rot - Lint staining - 2

Boll rot - Lint staining - 3.jpg