Schumann, G.L. 2000. Ergot. The Plant Health Instructor. DOI: 10.1094/PHI-I-2000-1016-01
Updated, 2005.

DISEASE:  Ergot of rye

PATHOGEN:  Claviceps purpurea

HOSTS:  Rye (principal economic host), barley, oats, triticale, wheat, and numerous species of cultivated and wild grasses

Authors
Gail L. Schumann
University of Massachusetts

Although ergot of rye causes yield reductions, the significance of the disease is primarily related to the various toxic alkaloids present in the ergots (sclerotia). The alkaloids can cause severe health problems in both humans and animals. Before this disease was understood, the ergots were ground up along with rye grains and ingested when the flour was used for baking. In the Middle Ages, this led to a frightening disease of humans known as "holy fire" or "St. Anthony’s fire." Today, ergot poisoning is mostly a concern in animals that may be given contaminated feed or graze where wild grasses are heavily infected with ergot.

(Left) Ergot on rye. Courtesy R.A. Kilpatrick.   (Right) St. Anthony. From a woodcut made in Germany about 1215 A.D. Courtesy Staatliche Graphische Sammlung München, Munich, Germany. Redrawn from the original.