Ergot "C. lutea" (on paspalum). "C. purpurea" most commonly affects outcrossing species such as rye (its most common host), as well as triticale, wheat, and barley. It affects oats only rarely. "C. purpurea" has at least three races or varieties, which differ in their host specificity: An ergot kernel, called a "sclerotium", develops when a spore of fungal species of the genus "Claviceps" infects a floret of flowering grass or cereal. The infection process mimics a pollen grain growing into an ovary during fertilization. Infection requires that the fungal spore have access to the stigma; consequently, plants infected by "Claviceps" are
Gum (botany) Gum (botany) Gum is a sap or other resinous material associated with certain species of the plant kingdom. This material is often polysaccharide-based and is most frequently associated with woody plants, particularly under the bark or as a seed coating. The polysaccharide material is typically of high molecular weight and most often highly hydrophilic or hydrocolloidal. Many gums occur as seed coatings for plant species; the adaptive purpose of some of these gummy coatings is to delay germination of certain flora seeds. An example of such a gummy coating occurs in the case of Western poison oak, a widespread shrub