• Leaves - whitish minute dots on leaves with irregular chlorotic areas on tip portion
• Circular to oblong concentric black velvety rings appear in chlorotic area
• Lesions develop towards the base of the leaves
• Leaves die from the tip downwards, break at the point of infection and hang down
• Bulbs – semi watery rot, shrinkage of the fleshy bulb scales and desiccation followed by these scales becoming dry and papery

• Mycelium - branched, coloured and septate
• Conidiophores - singly or in groups, septate, pale to mid brown
• Conidia - solitary, straight or curved

Mode of spread and survival :

• Carried through seed bulbs collected from infected field
• Spreads mainly through air borne spores
• Pathogen enters through stomata or wounds
• Survives in plant debris for 8 months

Epidemiology:

• Temp - 21 to 30oc
• RH - 90 %

• Seed treatment - thiram @ 2.5g/kg of seed
• Three sprays of Copper oxychloride - 0.25%, Chlorothalanil - 0.2% and Zineb - 0.2%
• Mancozeb - 0.2%
• Varieties - New Selection, Red Creole - resistant