Ustinaginales is also known and classified as the "smut fungi". They are serious plant pathogens, with only the dikaryotic stage being obligately parasitic.
They can infect corn plants (zea mays) producing tumor-like galls that render the ears unsaleable. This corn smut, is also known as huitlacoche and sold canned for consumption in Latin America.
References
^ Winter, G. (1880). Rabenhorsts Kryptogamen-Flora von Deutschland, Oesterreich und der Schweitz, Vol. 1. Leipzig: E. Kummer, 73. (as "Ustilagineae")
^ Bauer, R., et al. (1997). "Ultrastructural markers and systematics in smut fungi and allied taxa.". Can. J. Bot.75: 1311.
C.J. Alexopolous, Charles W. Mims, M. Blackwell et al., Introductory Mycology, 4th ed. (John Wiley and Sons, Hoboken NJ, 2004) ISBN 0-471-52229-5