Polyporaceae

Polyporus squamosus Molter

Cerioporus mollis (Polyporaceae), Zoelen, the Netherlands

Favolus tenuiculus - Flickr - Dick Culbert

Hapalopilus nidulans G7 (4)

2008-02-10 Polyporus umbellatus crop

Pycnoporus cinnabarinus (Jacq.) P. Karst 153

Polyporaceae is a family of fungi within the order Polyporales. Known for their ability to decompose wood, members of this family are significant in forest ecosystems and are also used in various traditional and modern applications. The Polyporaceae family includes species that form large, often tough, fruiting bodies known as polypores or bracket fungi. These fungi are primarily found on dead or dying trees, playing a crucial role in the nutrient cycle by breaking down the cellulose and lignin in wood.

Characteristics

Polyporaceae species produce fruiting bodies that can be annual or perennial. These structures are typically attached to wood substrates, including fallen logs, standing dead trees, and even the wood of living trees, causing decay. The fruiting bodies are characterized by their pores, which house the spore-producing structures, or basidia. The pore surface can vary in color, but it is often white, cream, or yellowish.

The spores produced by Polyporaceae are typically small, cylindrical to allantoid (sausage-shaped), and non-amyloid, meaning they do not stain blue or black with iodine-based reagents. This feature is a key identification characteristic in microscopy studies of these fungi.

Ecology

Polyporaceae fungi are predominantly saprotrophic, decomposing dead wood and contributing to the carbon cycle in forest ecosystems. Some species, however, are parasitic and can cause significant damage to living trees, leading to diseases such as white rot and brown rot. White rot fungi decompose all components of wood, including lignin, resulting in a whitish, fibrous residue. Brown rot fungi primarily decompose cellulose and hemicellulose, leaving behind the brownish lignin.

These fungi are found worldwide, from tropical to temperate regions, and play a vital role in their ecosystems by breaking down wood that would otherwise accumulate, thus facilitating nutrient recycling.

Economic and Cultural Significance

Several species within the Polyporaceae family have been used in traditional medicine, particularly in East Asia. For example, Ganoderma lucidum (Reishi or Lingzhi) and Trametes versicolor (Turkey Tail) are well-known for their purported health benefits and have been the subject of scientific research for their potential in cancer therapy and immune system support.

In addition to their medicinal uses, some polypores are used in the art of spalting, a process that involves using fungi to create patterns in wood for decorative purposes. Moreover, certain species have been explored for their potential in bioremediation, the use of living organisms to detoxify or remove pollution from the environment.

Classification

The classification of Polyporaceae has undergone significant changes with the advent of molecular phylogenetics, which has helped clarify the relationships between different genera and species within the family. As of now, the family includes a wide range of genera, but the exact number and delineation of these genera can vary between different taxonomic treatments.

Genera

Some notable genera within the Polyporaceae include:

• Ganoderma
• Fomes
• Trametes
• Polyporus

Conservation

While many Polyporaceae species are common and not considered at risk, habitat destruction and pollution have led to the decline of some species. Conservation efforts are important to preserve the biodiversity of these fungi and the roles they play in ecosystems.