Macalpinomyces neglectus (Niessl) Vánky

Synonyms

Erysibe panicorum var. panici-glauci Wallr.
Sporisorium neglectum (Niessl) Vánky
Ustilago neglecta Niessl
Ustilago panici-glauci (Wallr.) G. Winter

Description

Sori in all flowers of an inflorescence, ovoid, often acuminate, 2–4 mm long, partly enclosed by the glumes, covered by a thin greyish peridium of fungal and host tissues which ruptures irregularly to expose the dark brown powdery mass of spores mixed with irregular groups of sterile cells. Columella short, stout, formed of host tissues and fungal cells. Infection systemic.

Spores subglobose, ovoid, elongate to slightly irregular, 9–14 × 8–11 µm, medium brown; wall uniformly c. 0.8 µm thick, prominently and abundantly echinulate; spore profile serrulate; in SEM the area between the spines with small rounded scattered warts.

Sterile cells in groups, chains or solitary (in some specimens sparse), smaller than the spores (5–12 µm long), round or irregular, collapsed in old specimens, hyaline, usually with a light-refractive droplet.

Hosts
   
Host family: Poaceae
   
Host species: Setaria pumila (Poir.) Roem. & Schult.
Setaria sphacelata (Schumach.) Stapf & C.E.Hubb.

Distribution

States & Territories: NSW, QLD

Comments

There are slight variations in spore dimensions and in the abundance of sterile cells between collections from different parts of the world.