Many different grasses may become contaminated with ergot alkaloids. Claviceps purpurea may infect the reproductive structures of cereal plants during cool, wet weather, with rye being the main economic host. Specialized fungal structures known as sclerotia (the ergots) develop from these reproductive structures and may be harvested with the grain [ Figure 7 ]. If the sclerotia are processed into flour, high levels of contamination with ergot alkaloids may result. Claviceps africana and C. sorghi may contaminate sorghum with ergot alkaloids worldwide [ Figure 8 ], but the relative toxicity of mycotoxins produced by these fungi has not been evaluated in detail. Common pasture grasses may be contaminated with alkaloids similar to those produced by ergot fungi, but these fungi belong to different genera and do not produce sclerotia. Click here for a plant disease lesson on ergot.