Late leaf spot

Symptom

Lesions of late leaf spot are usually smaller, more nearly circular without yellow halo, and darker in color than those of early leaf spot. On the lower surface, where most sporulation occurs, the lesions are black with a slightly rough appearance. As the disease progresses the spots enlarge until the entire leaf is affected. In addition to causing leaf spots, pathogen also produce lesions on petioles, stem, and pegs. These are oval to elongate and have more distinct margins than the leaflet lesion. When disease attack is severe, the affected leaflets first become chlorotic, then necrotic lesions often coalesce and leaflets are shed.