Tom Volk's Fungus of the Month for October 1999

This month's fungus is Claviceps purpurea, cause of ergotism-- and likely contributor to the Salem Witch Trials

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Claviceps purpurea on ryeThis month's fungus is a plant parasite, commonly found on grains of rye (as shown here) or sometimes on other grasses such as quackgrass. The fungus infects the flowers when they're young and cause the growths you see. It induces the cells to divide (hyperplasia) and to enlarge (hypertrophy), creating the relatively large brown sclerotia to the left. These sclerotia are hard resting structures that allow the fungus to survive adverse conditions, such as winter and desiccation. In the life cycle of this organism, the sclerotia fall to the ground and overwinter, germinating in the spring to produce a stroma that contains perithecia, which produces spores to. Someday I'll have a good picture of this to put online-- the stroma are fragile and don't photograph well so far.

It's really not a devastating parasite to the plant. You might think its main detriment is that is replaces one of the grains of the plant, thus reducing yield. However it also draws nutrients away from the other uninfected grains so that they become stunted, thus reducing yield quite a bit more. But its worst problem is when the sclerotia inadvertently get mixed in with the grains and are incorporated into foods, thus causing a devastating and sometimes deadly syndrome called ergotism in humans and other animals.

Ergotism is caused by the chemicals in the fungus called ergot (pronounced AIR-got). Consumption of foods contaminated with ergot and ergot derivatives may cause vomiting, diarrhea, hallucinations, and may lead to gangrene in serious cases. Historically the fungus has been implicated in epidemics causing thousands of fatalities, but due to increased knowledge of this fungus and a more varied modern diet such epidemics no longer occur in humans. However, chronic exposure through consumption of contaminated foods can lead to health complications.

However as recently as 1951, in Pont-St. Esprit, a small town in France, there was an outbreak of the disease. First a bit of background-- in Europe it is the custom to buy fresh bread nearly every day. Much more civilized than our American custom of buying bread with preservatives in it that allow it to last several weeks. In this small town there was only one bakery and everyone bought bread from it. Strange things started happening. People developed a burning sensation in their limbs, began to hallucinate that they could fly, did strange things to their dogs with forks and in general acted weirdly. This outbreak is chronicled in a marvelous (but out of print) book called "The day of St Anthony's Fire" by John Grant Fuller. St. Anthony is the patron saint of lost causes (incidentally I went to St. Anthony's church until I was about 18). When all of the other saints have failed, St. Anthony is the one you are supposed to pray to. And St. Anthony's fire was rampant in the town that day. Similar outbreaks probably occurred throughout the world wherever the conditions were right for the growth of Claviceps purpurea. The chemical responsible for the hallucinations is actually LSD! lysergic acid. There was even an outbreak of egotism on the television show "Quincy" starring Jack Klugman, who played a coroner. He was aboard a cruise ship and people were acting very strangely. Quincy finally traced the behavior to contamination of the flour tortillas that had been served aboard ship. I haven't seen this episode for 15 years, but I still remember it because I figured it out before Quincy did!

After I published this page I got an email from Barbara Shew of North Carolina State University, who wrote:

"The X-Files also had an episode featuring ergot, although it had a surreal twist (of course). In that episode, Scully got a tattoo that caused her to hallucinate (she thought the tattoo was talking to her). Turns out the tattoo artist was an ex-con who learned his art in prison. He collected plants in the prison yard and extracted dyes from them for his tattoos. One of the grasses he used was infected with ergot, hence the hallucinations. A really big stretch, but fun anyway!"

Thanks Barbara! It just goes to show you that fungi are everywhere!

Another ergot derivative may cause spontaneous abortions in animals-- in small doses this same drug is used to aid in childbirth. Another of the ergot derivatives is used to cure migraine headaches. For a time there was even a rock band called "The ergot derivative" from Australia, which apparently disbanded in 1998.

animated witchSo what does this all have to do with the Salem Witch Trials, which took place near Salem Massachusetts in the late 1600's? There have been various attempts to explain those witch trials. None of them are more logical and interesting than the hypothesis of ergot poisoning, caused by Claviceps purpurea. The behavior was not identified as witchcraft until 1691, and this was just the beginning of the problem. Many people were sent to trial and often convicted and imprisoned. By September 1692 twenty men and women had been put to death for their crimes. All of the accused had similar symptoms: manic melancholia, psychosis, delirium, crawling sensations of the skin, vertigo, headaches, vomiting and diarrhea. All of these are symptoms of ergot poisoning, and it is likely that at list the initial hysteria was started by Claviceps purpurea infecting the grains of rye. This was chronicled in an article (Science 192:21-26, 1976) by Linnda R. Caporael called "Ergotism: The Satan Loosed in Salem?" She provides compelling, although circumstantial, evidence that the Salem witch trials coincided with a weather period that would have produced large quantities of ergot on rye, which was grown in the lowlands in that area. Here are some other links to learn more about the Salem Witch trials: You should also get yourself a copy of George Hudler's book "Magical mushrooms, mischievous molds" from Princeton University Press (ISBN 0-691-02873-7). Dr. Hudler, of Cornell University, has described more details about the Salem Witch Trials, as well as the impact of many other fungi and fungal diseases on history. It's a must-have for anyone interested in mycology and plant pathology. I recommend this book very highly. GET TO A BOOKSTORE AND GET THIS BOOK RIGHT NOW!
There's many interesting stories about the impact of fungi on history, and this is just one of them. Who would have thought a little disease on grain could wreak such havoc with the population?

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This page and other pages are © Copyright 1999 by Thomas J. Volk, University of Wisconsin-La Crosse.

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