Fungal causal agent: Phyllosticta sp.

Symptoms: Large circular or irregular shaped leaf spots with tan centers. The infected tissue becomes very thin, and breaks out reaching a diameter of 1 cm or larger. 

Management:  Keeping leaf wet for a long time is a major cause of infection primarily through water-splashed spores. Manage overhead irrigation with minimal chances of continued long periods of leaf wetness. If the problem is a continuous one, use protective fungicides before any infection can happen. Fungicide management may be difficult once the symptoms develop. 

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