Corn smut
Ustilago maydis
Corn smut is a plant disease caused by the pathogenic fungus ''Ustilago maydis'' that causes smut on maize and teosinte. The fungus forms galls on all above-ground parts of corn species, and is known in Mexico as the delicacy ''huitlacoche''; it is eaten, usually as a filling, in quesadillas and other tortilla-based foods, and soups.