Chapter 22: Phylum Basidiomycota: Other Basidiomycetes

The chapter surveys the major functional groups within this order, including polypores or bracket fungi that form hard, persistent woody fruiting bodies with pored undersurfaces, coral fungi displaying delicate branched or upright morphologies, tooth fungi characterized by spine-like or tooth-like hymenial structures, and resupinate or crust fungi that grow as thin layers across their substrates without forming distinct fruiting bodies. The ecological significance of Aphyllophorales is substantial, as these organisms function as primary decomposers in forest ecosystems, breaking down dead wood and plant material while simultaneously participating in nutrient mineralization and carbon cycling processes. Many species establish ectomycorrhizal associations with tree roots, facilitating nutrient exchange and enhancing host plant fitness. The chapter details how basidiospore maturation and dispersal occur on specialized hymenial surfaces, with morphological adaptations reflecting different strategies for spore liberation and environmental tolerance. Wood decay mechanisms are examined, distinguishing between white rot fungi that degrade both cellulose and lignin and brown rot fungi that selectively decompose cellulose, leaving oxidized lignin residues. Economic implications are discussed, highlighting the destructive capacity of wood-decay species in forestry and timber industries, while also acknowledging the pharmaceutical and cultural value of certain Aphyllophorales species in traditional medicine and contemporary applications. The chapter further contextualizes these non-gilled basidiomycetes within broader fungal evolution, illustrating morphological and reproductive transitions between the Aphyllophorales and gilled mushroom orders, demonstrating the adaptive radiation and ecological success of this substantial fungal group.