Causal Agent: 

Fungi (Corynespora cassiicola)

Characteristic Symptoms:
Initial symptoms appear as small, necrotic lesions with light brown center and dark brown marginal rings that develop into large spots with characteristic target-shaped rings.
Several spots can be observed on the leaf surface under favorable conditions leading to blighting of the leaves.
Conditions for Disease Development:
The disease is favored by moderate temperatures (20-28°C) and extended periods of leaf wetness (16h or more).
The fungus infects many crops including pepper, cucumber, papaya, ornamentals and weeds.
The fungus can colonize weeds or other crops and remains viable for up to two years.
The disease is spread by air-borne conidia/spores.
Rain splashes or windblown soil particles create wounds for spores to enter.
Management and Control:
Use disease-free seedlings.
Proper plant spacing can help reduce extended periods of leaf wetness.
Maintain good field sanitation (e.g. remove and burn heavily affected leaves; remove weeds).
Preventive application of chlorothalonil fungicides  (e.g. Daconil®, Agronil®, Yoda®, Rover®, Yoda 500Ⓡ,) and mancozeb  (e.g. Attain M-80Ⓡ, Achem Mancozeb 80 WPⓇ, Micron 80 WOⓇ, VanzebⓇ).

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