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Mycelium
Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are found in and on soil and many other substrates. A typical single spore germinates into a monokaryotic mycelium, which cannot reproduce sexually; when two compatible monokaryotic mycelia join and form a dikaryotic mycelium, that mycelium may form fruiting bodies such as mushrooms. A mycelium may be minute, forming a colony that is too small to see, or may grow to span thousands of acres as in '' Armillaria''. Through the mycelium, a fungus absorbs nutrients from its environment. It does this in a two-stage process. First, the hyphae secrete enzymes onto or into the food source, which break down biological polymers into smaller units such as monomers. These monomers are then absorbed into the mycelium by facilitated diffusion and ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ectomycorrhizal Extramatrical Mycelium
Ectomycorrhizal extramatrical mycelium (also known as extraradical mycelium) is the collection of filamentous fungal hyphae emanating from ectomycorrhizas. It may be composed of fine, hydrophilic hypha which branches frequently to explore and exploit the soil matrix or may aggregate to form rhizomorphs; highly differentiated, hydrophobic, enduring, transport structures. Characteristics Overview Apart from mycorrhizas, extramatrical mycelium is the primary vegetative body of ectomycorrhizal fungi. It is the location of mineral acquisition, enzyme production, and a key means of colonizing new root tips. Extramatrical mycelium facilitates the movement of carbon into the rhizosphere, moves carbon and nutrients between hosts and is an important food source for invertebrates. Exploration type The mycelial growth pattern, extent of biomass accumulation, and the presence or absence of rhizomorphs are used to classify fungi by exploration type. Agerer first proposed the designat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
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 of the kingdom (biology)#Six kingdoms (1998), traditional eukaryotic kingdoms, along with Animalia, Plantae, and either Protista or Protozoa and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of motility, mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mushroom
A mushroom or toadstool is the fleshy, spore-bearing Sporocarp (fungi), fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally refers to a poisonous mushroom. The standard for the name "mushroom" is the cultivated white button mushroom, ''Agaricus bisporus''; hence, the word "mushroom" is most often applied to those fungi (Basidiomycota, Agaricomycetes) that have a stem (Stipe (mycology), stipe), a cap (Pileus (mycology), pileus), and gills (lamellae, sing. Lamella (mycology), lamella) on the underside of the cap. "Mushroom" also describes a variety of other gilled fungi, with or without stems; therefore the term is used to describe the fleshy fruiting bodies of some Ascomycota. The gills produce microscopic Spore#Fungi, spores which help the fungus spread across the ground or its occupant surface. Forms deviating from the standard Morphology (biology), morphology usually have more specific names, such as "bolete", " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arbuscular Mycorrhiza
An arbuscular mycorrhiza (AM) (plural ''mycorrhizae'') is a type of mycorrhiza in which the symbiont fungus (''Arbuscular mycorrhizal fungi'', or AMF) penetrates the cortical cells of the roots of a vascular plant forming arbuscules. Arbuscular mycorrhiza is a type of endomycorrhiza along with ericoid mycorrhiza and orchid mycorrhiza (not to be confused with ectomycorrhiza). They are characterized by the formation of unique tree-like structures, the arbuscules. In addition, globular storage structures called vesicles are often encountered. Arbuscular mycorrhizae are formed by fungi in the subphylum Glomeromycotina. This subphylum, along with the Mortierellomycotina, and Mucoromycotina, form the phylum Mucoromycota, a sister clade of the more well-known and diverse dikaryan fungi. AM fungi help plants to capture nutrients such as phosphorus, sulfur, nitrogen and micronutrients from the soil. It is believed that the development of the arbuscular mycorrhizal symbiosis playe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 until favorable growth conditions return. Sclerotia initially were mistaken for individual organisms and described as separate species until Louis René Tulasne proved in 1853 that sclerotia are only a stage in the life cycle of some fungi. Further investigation showed that this stage appears in many fungi belonging to many diverse groups. Sclerotia are important in the understanding of the life cycle and reproduction of fungi, as a food source, as medicine (for example, ergotamine), and in agricultural blight management. Examples of fungi that form sclerotia are ergot (''Claviceps purpurea''), '' Polyporus tuberaster'', '' Psilocybe mexicana'', '' Agroathelia delphinii'' and many species in Sclerotiniaceae. Although not fungal, the plas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 or more cells surrounded by a tubular cell wall. In most fungi, hyphae are divided into cells by internal cross-walls called "septa" (singular septum). Septa are usually perforated by pores large enough for ribosomes, mitochondria, and sometimes nuclei to flow between cells. The major structural polymer in fungal cell walls is typically chitin, in contrast to plants and oomycetes that have cellulosic cell walls. Some fungi have aseptate hyphae, meaning their hyphae are not partitioned by septa. Hyphae have an average diameter of 4–6 μm. Growth Hyphae grow at their tips. During tip growth, cell walls are extended by the external assembly and polymerization of cell wall components, and the internal production of new cell membrane. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armillaria
''Armillaria'' is a genus of fungi that includes the '' A. mellea'' species ('honey fungus') that live on trees and woody shrubs. It includes about 10 species formerly categorized summarily as ''A. mellea''. ''Armillaria'' sp. are long-lived and form the largest living fungi in the world. The largest known specimen (an ''A. ostoyae'') covers more than in Oregon and is estimated to be 2,500 years old. Some species of ''Armillaria'' display bioluminescence. ''Armillaria'' can be a destructive forest pathogen. It causes "white rot" root disease. As it feeds on dead plant material, it can kill its host with little negative effect to itself. Taxonomy The name ''Armillaria'' was defined in 1821 by Elias Magnus Fries, but at that time most gilled mushrooms were considered to belong to genus ''Agaricus'' and ''Armillaria'' was only a subgenus (a "tribe"). In 1857, Friedrich Staude established the independent genus. ''Armillaria'' species morphologically similar t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monokaryon
A monokaryon is a fungal mycelium or hypha in which each cell contains a single nucleus. It also refers to a mononuclear spore or cell of a fungus that produces a dikaryon in its life cycle. Merriam-Webster dictionary See also *Dikaryon
The dikaryon (karyogamy) is a cell nucleus feature that is unique to certain fungi. (The green alga '' Derbesia'' had been long considered an exception, until the heterokaryotic hypothesis was challenged by later studies.) Compatible cell-types c ...
References Mycology {{mycology-stub ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dikaryotic
The dikaryon (karyogamy) is a cell nucleus feature that is unique to certain fungi. (The green alga ''Derbesia'' had been long considered an exception, until the heterokaryotic hypothesis was challenged by later studies.) Compatible cell-types can fuse cytoplasms (plasmogamy). When this occurs, the two nuclei of two cells pair off and cohabit without fusing (karyogamy). This can be maintained for all the cells of the hyphae by synchronously dividing so that pairs are passed to newer cells. In the Ascomycota this attribute is most often found in the ascogenous hyphae and ascocarp while the bulk of the mycelium remains monokaryotic. In the Basidiomycota this is the dominant phase, with most Basidiomycota monokaryons weakly growing and short-lived. The formation of a dikaryon is a plesiomorphic character for the subkingdom Dikarya, which consists of the Basidiomycota and the Ascomycota. The formation of croziers in the Ascomycota and of clamp connections in the Basidiomycota f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporocarp (fungi)
The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cycle, while the rest of the life cycle is characterized by vegetative mycelial growth and asexual spore production. The sporocarp of a basidiomycete is known as a ''basidiocarp'' or ''basidiome'', while the fruitbody of an ascomycete is known as an '' ascocarp''. Many shapes and morphologies are found in both basidiocarps and ascocarps; these features play an important role in the identification and taxonomy of fungi. Fruitbodies are termed ''epigeous'' if they grow on the ground, while those that grow underground are '' hypogeous''. Epigeous sporocarps that are visible to the naked eye, especially fruitbodies of a more or less agaricoid morphology, are often called mushrooms. Epigeous sporocarps have mycelia that extend underground ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecosystem
An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and energy flows. Ecosystems are controlled by external and internal Environmental factor, factors. External factors—including climate—control the ecosystem's structure, but are not influenced by it. By contrast, internal factors control and are controlled by ecosystem processes; these include decomposition, the types of species present, root competition, shading, disturbance, and succession. While external factors generally determine which Resource (biology), resource inputs an ecosystem has, their availability within the ecosystem is controlled by internal factors. Ecosystems are wikt:dynamic, dynamic, subject to periodic disturbances and always in the process of recovering from past disturbances. The tendency of an ecosystem to remain clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
