Causative agent:  Sphaerulina oryzina (syn. Cercospora janseana, Cercospora oryzae).

Symptom:

• Panicle initiation.
• Light to dark brown, linear, and progress parallel to the vein.
• On glumes, lesions are usually shorter but can be wider than those on the leaves. Brown lesions are also found on pedicels.
• The disease also causes discoloration on the leaf sheath, referred to as “net blotch” because of the netlike pattern of brown and light brown to yellow areas
• Narrow brown spot can be confused with white leaf streak. White leaf streak are oblong, white to creamish white, delimited by narrow brown margins, amphigenous, and interveinal.