Causal Agent: 

Fungus (Corynespora cassiicola)

Characteristic Symptoms:
Initially, small, pinpoint, dark brown or water-soaked spots appear on the upper surface of the older leaves that eventually increase in size (up to 2 cm diameter), becoming circular and with concentric rings.
Spots on the upper leaf surface are pale yellow and indistinct.
Leaf spots are almost similar to early blight except for the absence of intense yellowing around the spot, which is a characteristic of early blight disease.
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 crop 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 in the fruit 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 (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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