Corn smut

Corn smut is a plant disease caused by the pathogenic fungus Ustilago maydis. One of several cereal crop pathogens called smut, the fungus forms galls on all above-ground parts of corn species such as maize and teosinte. The infected corn is edible: in Mexico, it is considered a delicacy called huitlacoche, often eaten as a filling in quesadillas and other tortilla-based foods, as well as in soups. In Mexico, corn smut is known as huitlacoche ((ɡ)witlaˈkotʃe, sometimes spelled cuitlacoche). This word entered Spanish in Mexico from Classical Nahuatl, though the Nahuatl words from which huitlacoche is derived are debated. In modern Nahuatl, the word for huitlacoche is cuitlacochin (kwit͡ɬɑˈkot͡ʃin), and some sources deem cuitlacochi to be the classical form. Some sources wrongly give the etymology as coming from the Nahuatl words cuitlatl ˈkwit͡ɬɑt͡ɬ ("excrement" or "rear-end", actually meaning "excrescence") and cochtli ˈkot͡ʃt͡ɬi ("sleeping", from cochi "to sleep"), thus giving a combined mismeaning of "sleeping/hibernating excrement", but actually meaning "sleeping excrescence", referring to the fact that the fungus grows between the kernels and impedes them from developing, thus they remain "sleeping". A second group of sources deem the word to mean "raven's excrement". These sources appear to be combining the word cuitlacoche for "thrasher" with cuitla, meaning "excrement", actually meaning "excrescence". However, the avian meaning of cuitlacoche derives from the Nahuatl word "song" cuīcatl ˈkwiːkɑt͡ɬ, itself from the verb "to sing" cuīca ˈkwiːkɑ. This root then clashes with this reconstruction's second claim that the segment cuitla- comes from cuitla ("excrement"). One source derives the meaning as "corn excrescence", using cuītla again and "maize" tlaōlli t͡ɬɑˈoːlːi. This requires the linguistically unlikely evolution of tlaōlli "maize" into tlacoche. In Peru, it is known as chumo or pacho. U. maydis is the best known and studied of the Ustilaginomycetes, a sub class of basidiomycota, and so is often used as the exemplar species when talking about its entire class.