The gleba is the interior mass of fungal tissue that produces and contains spores in a range of fungi, especially those with enclosed fruiting bodies. In these species the gleba develops inside an outer layer (the peridium) and changes in texture and color as it matures. It is a hallmark of so-called gasteroid fungi but is also present in a number of unrelated groups that evolved similar reproductive structures.

Characteristics and structure

Gleba may be compact and fleshy, powdery, or gelatinous depending on the species and the stage of development. Typical components include spore-producing cells (basidia or asci, depending on the fungal lineage), a supporting network of fibres or sterile threads called capillitium in some taxa, and air spaces or fluids that influence texture. The outer covering, or peridium, protects the gleba until spores become ready for release.

Development and maturation

During fruiting-body development the gleba undergoes biochemical and physical changes: immature gleba is often firm and pale, then darkens and dries or liquefies as spores mature. In some fungi the gleba breaks down into a dry powder that can be carried away by wind; in others it becomes odorous or sticky to attract insects or vertebrates that will disseminate spores.

Dispersal strategies and ecology

Different gleba forms reflect distinct dispersal methods. Powdery gleba is typical of puffballs, which release clouds of spores when compressed. Fungi such as stinkhorns produce a foul-smelling, sticky gleba that attracts flies and other insects which transport the spores. Hypogeous fungi (for example truffles) offer an aromatic gleba that entices mammals to dig them up and consume them, passing spores in droppings.

Examples and notable facts

  • Puffballs: gleba becomes a dry spore mass expelled through an aperture.
  • Stinkhorns: gleba is odorous and slimy, spread by insects.
  • Truffles and other subterranean fungi: gleba is scented to attract animals.

In mycology the term is a simple way to refer to internal spore-bearing tissue; it is often discussed alongside anatomy terms like peridium and capillitium. For general information on spore biology see spore references. The form and fate of the gleba are important for identification, ecology and for edible or economically important species, but it can also be a cautionary feature: some poisonous fungi produce glebal changes that resemble edible taxa at certain stages, so accurate identification is essential.