These fungi are saprophytes, are not host specific and so can affect all cereals.
The usual symptoms of sooty moulds are a darkening of the ears before harvest. This is commonly seen when weather conditions are wet, but severe symptoms are often associated with root or stem base diseases which cause premature ripening of the crop. Delays in harvesting in wet weather can lead to severe blackening of ears which can lead to discolouration of the grain.
The fungi that can cause sooty moulds are very common in the atmosphere and can survive adverse conditions as spores or as mycelium on a wide range of materials. They do not require living host material to survive.
The discolouration of ears and grain rarely have any effect on grain yield but the mixing of spores with the grain at harvest can lead to discolouration which will affect marketability, particularly if the grain is planned for milling for flour production.