The infection is usually systemic and destroys either the entire
inflorescence or all of the ovaries or spikelets.
Langdon & Fullerton (1978) examined the soral ontogeny of
several species included in Clade 1, namely Sporisorium andropogonis,
S. sorghi and S. vanderystii. They observed that
the columella began to form after intercellular hyphae became
confluent and caused the host cells to proliferate. Hyphae at
the periphery of the columella formed a sheath of elongated