''Ceratobasidium'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

fungi A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

in the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Cantharellales The Cantharellales are an order (biology), order of fungi in the class (biology), class Agaricomycetes. The order includes not only the chanterelles (Cantharellaceae), but also some of the tooth fungi (Hydnaceae), clavarioid fungi (Aphelariaceae ...

Basidiocarps In fungi, a basidiocarp, basidiome, or basidioma () is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do no ...

(fruit bodies) are effused and the genus is sometimes grouped among the

corticioid fungi The corticioid fungi are a group of fungi in the Basidiomycota typically having effused, smooth basidiocarps (fruit bodies) that are formed on the undersides of dead tree trunks or branches. They are sometimes colloquially called crust fungi or pa ...

, though species also retain features of the

heterobasidiomycetes Heterobasidiomycetes, including jelly fungi, smuts and rusts, are basidiomycetes with septate basidia. This contrasts them to homobasidiomycetes (alternatively called holobasidiomycetes), including most mushrooms and other Agaricomycetes, whi ...

Anamorphic Anamorphic format is a cinematography technique that captures widescreen images using recording media with narrower native Aspect ratio (image), aspect ratios. Originally developed for 35 mm movie film, 35 mm film to create widescreen pres ...

forms were formerly referred to the genus ''Ceratorhiza'', but this is now considered a synonym of ''

Rhizoctonia ''Rhizoctonia'' is a genus of fungi in the family Ceratobasidiaceae. Species form thin, effused, corticioid basidiocarps (fruit bodies), but are most frequently found in their sterile, anamorph state. ''Rhizoctonia'' species are saprotrophic, ...

''. ''Ceratobasidium'' species, excluding the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

, are also now considered synonymous with ''Rhizoctonia'' and some species have been transferred to the latter genus. Species are

saprotrophic Saprotrophic nutrition or lysotrophic nutrition is a process of chemoheterotrophic extracellular digestion involved in the processing of decayed (dead or waste) organic matter. It occurs in saprotrophs, and is most often associated with fungi ...

, but several are also

facultative Facultative means "optional" or "discretionary" (antonym ''obligate''), used mainly in biology in phrases such as: * Facultative (FAC), facultative wetland (FACW), or facultative upland (FACU): wetland indicator statuses for plants * Facultative ...

plant pathogens Plant diseases are diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like orga ...

, causing a number of commercially important crop diseases. Some are also endomycorrhizal associates of

orchids Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan plants that are found in almost every habitat on Earth ...

Taxonomy

The name ''Ceratobasidium'' was introduced in 1935 by American mycologist D.P. Rogers to accommodate species of the old

form genus Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships. Form classification, generally restricted to palaeontology, reflects uncertainty; the goal of sc ...

'' Corticium'' that showed affinities with the

. These affinities were the possession of large

sterigmata In biology, a sterigma (: sterigmata) is a small supporting structure. It commonly refers to an extension of the basidium (the spore-bearing cells) consisting of a basal filamentous part and a slender projection which carries a spore at the tip ...

("cerato basidium" means "horned

basidium A basidium (: basidia) is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. The presence of basidia is one of the main characteristic features of the group. These bodies are also ...

") and the production of

basidiospores A basidiospore is a reproductive spore produced by basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts, and smuts. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are pr ...

that produce secondary spores. Four species were originally placed in the genus, with subsequent authors adding a further 35 species. The genus ''Ceratorhiza'' was introduced for

anamorph In mycology, the terms teleomorph, anamorph, and holomorph apply to portions of the life cycles of fungi in the phyla Ascomycota and Basidiomycota: *Teleomorph: the sexual reproductive stage (morph), typically a fruiting body. *Anamorph: an ase ...

s of ''Ceratobasidium'' by R.T. Moore in 1987, distinguishing them from anamorphs of ''Thanatephorus'' which were retained in ''Rhizoctonia''.

Current status

Molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

research, based on

cladistic Cladistics ( ; from Ancient Greek 'branch') is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is ...

analysis of

DNA sequences A nucleic acid sequence is a succession of bases within the nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. This succession is denoted by a series of a set of five different letters that indicate the order of the ...

, places ''Ceratobasidium'' (excluding the type species) within the Cantharellales. Following changes to the

International Code of Nomenclature for algae, fungi, and plants The ''International Code of Nomenclature for algae, fungi, and plants'' (ICN or ICNafp) is the set of rules and recommendations dealing with the formal botanical names that are given to plants, fungi and a few other groups of organisms, all tho ...

, the practice of giving different names to teleomorph and anamorph forms of the same fungus was discontinued, meaning that ''Ceratorhiza'' became a synonym of the earlier name ''Ceratobasidium''. DNA evidence also placed ''Ceratobasidium'' species (excluding the type species) in the genus ''Rhizoctonia''. Research on the

septal pore In algal anatomy, a pit connection is a hole in the septum between two algal cells, and is found only in multicellular red algae − specifically in the subphylum Eurhodophytina, except haploid Bangiales. They are often stoppered with proteinaceous ...

ultrastructure Ultrastructure (or ultra-structure) is the architecture of cells and biomaterials that is visible at higher magnifications than found on a standard optical light microscope. This traditionally meant the resolution and magnification range of a c ...

of the little-known and atypical type species, '' Ceratobasidium calosporum'', indicates that it is a member of the

Auriculariales The Auriculariales are an order of fungi in the class Agaricomycetes. Species within the order were formerly referred to the " heterobasidiomycetes" or "jelly fungi", since many have gelatinous basidiocarps (fruit bodies) that produce spores on ...

and is unrelated to other species of ''Ceratobasidium''. This taxonomic problem has not yet been resolved.

Description

Fruit bodies are effused, thin and often inconspicuous, smooth, waxy to dry and web-like, whitish to pale grey. Microscopically they have comparatively wide

hypha A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one o ...

e without

clamp connection A clamp connection is a hook-like structure formed by growing hyphal cells of certain fungi. It is a characteristic feature of basidiomycete fungi. It is created to ensure that each cell, or segment of hypha separated by septa (cross walls), rece ...

s and

basidia A basidium (: basidia) is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. The presence of basidia is one of the main characteristic features of the group. These bodies are also ...

that are spherical to cuboid or broadly club-shaped. Basidia bear 2 to 4

sterigma In biology, a sterigma (: sterigmata) is a small supporting structure. It commonly refers to an extension of the basidium (the spore-bearing cells) consisting of a basal filamentous part and a slender projection which carries a spore at the tip ...

ta, which are comparatively large.

Basidiospore A basidiospore is a reproductive spore produced by basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts, and smuts. Basidiospores typically each contain one haploid Ploidy () is the number of complete sets of chromos ...

s are globose to cylindrical (elongated and worm-like in the type species), smooth, and colourless. They frequently produce secondary spores and germinate by hyphal tubes. Asexual

s produce hyphae (sometimes swollen) and occasionally

sclerotia A sclerotium (; : sclerotia () is a compact mass of hardened fungal mycelium containing food reserves. One role of sclerotia is to survive environmental extremes. In some higher fungi such as ergot, sclerotia become detached and remain dormant u ...

(small propagules composed of thick-walled hyphae).

Habitat and distribution

Species are mainly

, occurring in the soil and producing fruit bodies on dead stems and plant detritus. Some occur on attached leaves and stems. Several species have been isolated from

orchid mycorrhiza Orchid mycorrhizae are endomycorrhizal fungi which develop symbiotic relationships with the roots and seeds of plants of the family Orchidaceae. Nearly all orchids are myco-heterotrophic at some point in their life cycle. Orchid mycorrhizae are ...

. Distribution appears to be

cosmopolitan Cosmopolitan may refer to: Internationalism * World citizen, one who eschews traditional geopolitical divisions derived from national citizenship * Cosmopolitanism, the idea that all of humanity belongs to a single moral community * Cosmopolitan ...

Economic importance

''Ceratobasidium'' species are opportunistic parasites of plants, causing a variety of economically important diseases. Examples include: '' Ceratobasidium cereale'', the cause of sharp eyespot of

cereals A cereal is a grass cultivated for its edible grain. Cereals are the world's largest crops, and are therefore staple foods. They include rice, wheat, rye, oats, barley, millet, and maize (Corn). Edible grains from other plant families, suc ...

and '' Ceratobasidium oryzae-sativae'', the cause of aggregate sheath spot of

rice Rice is a cereal grain and in its Domestication, domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species ''Oryza sativa'' (Asian rice)—or, much l ...

References

{{Taxonbar, from=Q5063742 Cantharellales Agaricomycetes genera