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© 2000, The Board of Regents of the University of Nebraska on behalf of the University of Nebraska–Lincoln Extension. All rights reserved.


Storage molds of corn occur in Nebraska annually, potentially lowering grain quality. Mycotoxin contamination of corn occurs periodically, potentially affecting human and animal health. Learn how to identify the different types and their effects. Introduction In Nebraska, grain molds occur every year to varying degrees on field corn, seed corn, white corn, and other specialty corn hybrids. Most grain mold pathogens become associated with the kernel in the field; however, under certain conditions of temperature, relative humidity, and grain moisture, these molds can grow within the colonized kernel and even spread to adjacent kernels during transport and storage. Several issues are associated with grain molds in corn including lowered grain quality, effects on human health, and effects on animal health and reproduction. Most grain mold pathogens have the potential to lower grain quality by affecting feed efficiency or grain processing characteristics. Human health concerns include allergenicity and hypersensitivity associated with the inhalation of mold spores in grain storage facilities and acute or chronic disease associated with infection by some species of grain mold fungi. In addition, some grain mold pathogens produce compounds (mycotoxins) that can be toxic to farm animals, wildlife, or humans. The presence of mold, however, does not indicate contamination of the grain with mycotoxins. Only certain strains of certain fungal (mold) species have the potential to produce these potentially harmful compounds. Grain mold pathogens are also capable of causing disease in other parts of the plant. Fusarium graminearum and Fusarium verticillioides (formerly named F. moniliforme) cause stalk rots, grain molds, and are capable of producing different classes of mycotoxins within colonized kernels. Recent evidence suggests that the mycotoxins are produced during infection of the plant and although not essential, may play a role in disease development.