Initially, small circular to oval chlorotic lesions appearing mostly on older leaves (Figure 1).
Subsequently, the spots expand, turn brown, and gradually become necrotic. A reddish-brown border encircles them. Their diameter varies from 4 mm to 1 cm (figures 2 to 5).
The center of the spots clears up more or less and sometimes presents discreet concentric patterns. A yellow halo is visible.
Similar but elongated lesions are sometimes visible on petioles and stem.
Degraded fabrics dry out, split and eventually fall off; the leaf blade is thus partially riddled (figures 3 and 4).
Severely affected leaves turn yellow, wither, and may drop.
Signs : presence of black mycelial stroma, and fruiting bodies dotting the lesions and sometimes giving them a slightly light gray tint. These fructifications consist of grouped brownish conidiophores, bearing septate and slightly arcuate hyaline conidia.