Aspergillus Fumagatus Causes Witt Disease

In addition to their roles in the decay of plant and animal residues and in food spoilage, these fungi are of great significance to humans in other ways. Aspergillus fumagatus, a common inhabitant of heated compost, can cause respiratory disease in humans, and a number of related species may produce aflatoxin, a tumor-inducing alkaloid, in poorly stored, noldy grain. Species of both Penicillium and Aspergilllus are used extensively in commercial fermentations. This class also includes other species that causes diseases in humans, animals, and plants; for example, the fungus Ceraqtocystis ulmi is responsible for Dutch elm disease, other species cause a Witt diseases in oaks, and still other reduce the quality of lumber.

All fungi in the class Pyrenomycetes produce asci and ascospores as an organized hymenial layer in a fruiting body called a perithecium. The perithecium is a small, flask shaped structure with a thin wall that surrounds a basal tuff of asci; the opening at the top is called an ostiole. The ascospores are typical discharged violently from the tips of the asci as they sequentially protrude through the ostiole. This class includes many sprobes that grow on dung or cellulosic materials such as tree stumps and logs. Other species cause diseases of higher plants. They include Claviceps purpurea, which causes the disease Ergot of rye.