Definition

Smut is a plant disease caused by a smut fungus (Ustilaginales) in the Basidiomycota or the fungus itself; it is characterized by masses of dark brown or black, dusty to greasy masses of teliospores that generally accumulate in black, powdery sori.

Etymology. 1664, "black mark, stain," from verb smutten "debase, defile" (early 15c.), cognate with M.H.G. smotzen "make dirty," from W.Gmc. *smutt- (cf. M.H.G. smuz "grease, dirt," Ger. Schmutz "dirt," Ger. schmutzen "to make dirty"). The meaning "indecent or obscene language" is first attested 1668 (implied in smutty).

Discussion

The corn smut fungus is considered an edible mushroom -like delicacy in Mexico; some farmers intentionally inoculate their corm plants to create smutted ears. Spores of the fungus land upon corn silks and grow down teh silks into the ovaries.