from the wiki:
"Corn smut is a disease of maize caused by the pathogenic plant fungus Ustilago maydis. U. maydis causes smut disease on maize (Zea mays) and teosinte (Euchlena mexicana). Although it can infect any part of the plant it usually enters the ovaries and replaces the normal kernels of the cobs with large distorted tumors analogous to mushrooms. These tumors, or "galls", are made up of much-enlarged cells of the infected plant, fungal threads, and blue-black spores. The spores give the cob a burned, scorched appearance. In fact, the name Ustilago comes from the Latin word ustilare (to burn).
Considered a pest in most of the United States, smut feeds off the corn plant and decreases the yield. Usually smut-infected crops are destroyed. However in Mexico corn smut is called huitlacoche (IPA /wi.t͡ɬa.ko.t͡ɕe/), and is considered a delicacy, even being preserved and sold for a higher price than corn. For culinary use, the galls are harvested while still immature — fully mature galls are dry and almost entirely spore-filled. The immature galls, gathered two to three weeks after an ear of corn is infected, still retain moisture and, when cooked, have a flavor described as mushroom-like, sweet, savory, woody, and earthy. Flavor compounds include sotolon and vanillin, as well as the sugar glucose." rest at:
http://en.wikipedia.org/wiki/Corn_smutalso from the wiki:
Aflatoxins are naturally occurring mycotoxins that are produced by many species of Aspergillus; but most notably Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are toxic and carcinogenic to animals, including humans. After entering the body, aflatoxins are metabolized by the liver to an intermediate reactive, aflatoxin M1, an epoxide.
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The native habitat of Aspergillus is in soil, decaying vegetation, hay, and grains undergoing microbiological deterioration and it invades all types of organic substrates whenever and wherever the conditions are favorable for its growth. Favorable conditions include high moisture content (at least 7%) and high temperature.
Crops which are frequently affected include cereals (maize, sorghum, pearl millet, rice, wheat), oilseeds (peanut, soybean, sunflower, cotton), spices (chile peppers, black pepper, coriander, turmeric, ginger), and tree nuts (almond, pistachio, walnut, coconut).
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In 1989, Saddam Hussein ordered the government of Iraq to begin production of aflatoxin as an economic biological/chemical weapon. The methods used by Iraqi scientists at the Salman Pak facility were crude; Aspergillus was grown on wet rice and the final product was reportedly highly impure. According to UNSCOM estimations, 2200 L of aflatoxin were produced. Some of this material was reportedly loaded into missiles, though this allegation has never been proven as no aflatoxin was found after the 2003 invasion of Iraq by the United States. The presumption is that the aflatoxin was destroyed. source:
http://en.wikipedia.org/wiki/Aflatoxin