cercospora blight of asparagus

Cercospora blight-Initial symptoms on ferns may be the chlorotic and necrotic lesions on stems. Closer observations will reveal the light oval lesions with darker margins. The causal fungus may be observed in the center of lesions (in structures known as stomata) under appropriate conditions. 

Cercospora blight Figure 1. Cercospora blight of asparagus. At a distance, symptoms manifest themselves as chlorotic ferns.
Cercospora blight Figure 2. Cercospora blight of asparagus. Note sunken roughly oval or round lesions. Close observations will reveal sporulation in the lesions.
Cercospora blight Figure 3. Cercospora blight of asparagus. Note sunken roughly oval or round lesions. Close observations will reveal sporulation in the lesions.