Ans) Several Basidiomycetes cause illnesses in cereals and other economically important plants, causing significant production problems and possibly causing starvation in some regions of the world. Rusts and smuts are major pathogenic Basidiomycetes.Mushrooms have been a popular cuisine in recent years due to their flavour. Different Mushrooms, such as Agaricus, Pleurotus, and Volvoriella, are now farmed all over the world.Some mushrooms, such as Amanita spp., are extremely poisonous. Psilocybe spp., for example, produces hallucinogenic chemical compounds.As parasites, the polypores cause significant damage to forest trees, as well as to lumber like saprophytes.Basidiomycetous fungi's mycelia are important in the breakdown of organic matter and the recycling of nutrients. It's because they can manufacture a variety of extracellular enzymes that help break down complicated compounds like cellulose and lignin.