Close-up of one pustule with urediniospores.

Close-up of one pustule with urediniospores under dark-field observation.

Close-up of urediniospores showing echinulate surface under dark-field observation.

Urediniospores of a species of the fungus Tranzschelia.

Minute, raised spots surrounded by light green/white leaf tissue. Larger spots at the perimiter of image are infections of the fungus Phloeosporella padi.