Sori redirects here. For the commune in Italy, see Sori, Italy. Sori is a Comune (municipality in the Province of Genoa in the Italian region Liguria, located about 14 km southeast of Genoa

Sori on the underside of a curling fern.

The underside of a fertile frond of Dicksonia antarctica. Dicksonia antarctica, known as the Soft Tree Fern Man Fern or Tasmanian Tree Fern is an evergreen Tree fern native to parts of Australia, namely Each dot is an individual sorus.

In ferns, a sorus (pl. A fern is any one of a group of about 20000 Species of Plants classified in the phylum or division Pteridophyta, also known as Filicophyta sori) is a yellowish or brownish cluster of sporangia on the edge or underside of a fertile frond. A sporangium (pl sporangia) is a Plant or fungal structure producing and containing Spores Sporangia occur in angiosperms, A frond is a large Leaf with many divisions to it and the term is typically used for the leaves of palms Ferns or Cycads A frond is In some species, they are protected during development by a scale or film of tissue called the indusium, which forms an umbrella-like cover.

Sori occur on the sporophyte generation, the sporangia within producing haploid meiospores. All land plants and some Algae, have life cycles in which a haploid Gametophyte generation alternates with a Diploid sporophyte, the generation of a "Haplo" redirects here For the fictional character see The Death Gate Cycle. In Biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions As the sporongia mature, the indusium shrivels so that spore release is unimpeded. The sporangia then burst and release the spores.

The shape, arrangement, and location of the sori are often valuable clues in the identification of fern taxa. A taxon (plural taxa) or taxonomic unit, is a name designating an organism or a group of Organisms In Biological nomenclature according to Sori may be circular or linear. They may be arranged in rows, either parallel or oblique to the costa, or randomly. Their location may be marginal or set away from the margin on the frond lamina. The presence or absence of indusium is also used to identify fern taxa.

In fungi and lichens, a sorus is a cluster of sporangia surrounded by an external layer. A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Lichens (ˈlaɪkən or /lɪtʃən/ are symbiotic associations of a Fungus (the mycobiont with a photosynthetic partner (the photobiont also known as A sporangium (pl sporangia) is a Plant or fungal structure producing and containing Spores Sporangia occur in angiosperms,

Gallery

Fern sorus with immature sporangia

Circular sori with mature sporangia

Linear sori

Sori with indusia at different stages of development.

References and external links

• DiversityOfLife – Fern identification tool.
• Encyclopædia Britannica: sorus 2007. Encyclopædia Britannica Online. Retrieved 20 November 2007.