My Friends and Enemies (Interactions)

Claviceps purpurea has a TON of different relationships with a number of different species! We'll take a look at a number of different ways that this organism shows relationships with other organisms.

As we know, ergot is an obligate parasite on open-pollinated grasses such as rye, barley and wheat. It does NOT infect corn, Zea mays, like many people believe. If you do find something purple growing on your corn, it is probably corn smut. The reason that Claviceps purpurea is considered a parasite on these plants is because it steals the nutrients from the plant and is harming it in some way without doing anything in exchange for the nutrients. There are also some scientists, however, that consider this a mutualistic relationship (see more below). This parasitic relationship also has dire human effects in a couple of different ways. One way that it is bad is that it can kill crops and lead to a lower crop yield. It also can have dire effects on livestock (see more below). Well, what if you're not a farmer and you don't really care about crop yield and cows? Well, ergot is also a human pathogen, causing two different strains of ergotism in humans who ingest it.

Ergot is by some considered to have a mutualistic relationship with the plants it infects because in exchange for the nutrients that it takes, it provides protection for the plant from being eaten by insects and other animals. In other words, both organisms are getting some sort of benefit from this relationship. This is because after an insect or animal, like a cow, deer, horse, sheep or even a cute birdie eats the fungus, they will get sick from the ergot alkaloids. These chemicals produced by Claviceps purpurea give the animals ergotism. Animals can exhibit a number of different symptoms based on the specific strain of ergot that they consume, how often they eat it, climatic conditions under which the ergot grew, and the variations of alkaloid content. Symptoms ranging from backwards arching of the back, laying down, hyper-excitability, staggering and convulsions. It can also cause spontaneous abortions and gangrenous ergotism, which makes the hind limbs of the animal fall off! Clearly, this does not sound like an enjoyable experience for the animal and after this, they can smell the ergot and then avoid eating plants that are infected. To learn more about another fungal mutualism, check out this page on lichens!

Interactions with insects is an extremely important part of the ergot lifecycle and success. For the best dispersal, insects like butterflies and bees are needed as vectors to take the spores from one plant to another. The reason that this is considered a commensalism is because one organism (ergot) is gaining something by using another organism (the insect) without harming it.

To learn more about how this fungus has been used medicinally, check out MEDICINAL USES! Or else, you can always go HOME.