The rice leaf scald fungus, Rhynchosporium oryzae , produces sickle shaped to oblong apedicellate, hyaline conidia measuring 6–15 μm × 3–4.5 μm. They are bicellular and rarely 2-septate. Twelve strains isolated from the Ivory coast and Sierra Leone were studied and placed into four groups based on morphology on polished rice agar. Cardinal temperatures of these isolates were o, 24, 28 and 36 °C. The effect of various media and light on morphology was studied. Optimum concentration of glucose and peptone on dry weight was 1% and for sporulation on solid media was 1% peptone and 0.25% glucose. The fungus was found to be very variable in culture, especially with frequent subculturing.