Sarocladium oryzae grows slowly on potato dextrose agar producing colonies of 1.9 cm diameter in 5 days at 30 ° C. Aerial mycelium is sparse and pale orange, and the colony reverse is generally a darker orange. On oat agar colonies are whitish to pale pink or saffron at 21 ° C. Colony consistency varies with the isolate, but is usually cottony and sometimes powdery (Boa and Brady, 1987). The branched septate hyphae can be up to 2.5 µm thick, although gnarled wider hyphae also occur. The conidiophores are abundant and irregularly branched.