Insect pollinators are most likely the vectors for infection. Ustilago maydis has another interesting use in research projects. Although it usually exists as a mycelium in nature, in culture it grows as a single-celled yeast, so it can be manipulated exactly like Saccharomyces cerevisiae . A great deal is known about the physiology, genetics and molecular biology of this organism because of the ease with which it can be manipulated in the lab. I hope you enjoyed learning something about smut.
Every fungus has lots of interesting things about it.
I encourage you to explore further and learn more about fungi.