Causal Agent: 

Fungi (Colletotrichum lindemuthianum)

Characteristic Symptoms:
Lesions are sunken and light to dark brown on both sides of the leaves but usually more severe on the underside.
On petioles and branches, lesions are sunken, brown-black and are commonly slender to oval-shaped.
Symptoms on pods appear as light to dark brown sunken lesions with slightly raised, well-defined black ring margin. 
Conditions for Disease Development:
Frequent rainfall, presence of free moisture and cool to moderate temperatures (18-26°C) are critical factors for disease development.
The pathogen survives between crops on infected plant residue or infected volunteer plants and can be carried on seed harvested from infected fruit.
Conidia/spores produced on foliage are disseminated by wind, rain splashes, tools/implements and field workers.
Management and Control:
Use pathogen-free seed.
Remove and dispose infected plants/plant parts as soon as symptoms are observed to minimize spread of disease.
Avoid overhead irrigation or prolonged moisture to minimize disease incidence and severity.
Staking increases air movement and may help reduce infection in the field.
Deep plowing of crop residue immediately after harvest can effectively reduce inoculum carryover.
Crop rotation with non-host crops for at least 1 year may help reduce inoculum in the soil.
Apply copper–based fungicides as early as symptoms are observed or when conditions are favorable for disease development. (e.g. Cupravit®, Super BlueⓇ, Vitigran blueⓇ, FunguranⓇ, KocideⓇ, Hydroxide superⓇ).

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