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Rhizophydiales are an important group of chytrid fungi. They are found in soil as well as marine and fresh water habitats where they function as
parasites Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of lif ...
and
decomposer Decomposers are organisms that break down dead or decaying organisms; they carry out decomposition, a process possible by only certain kingdoms, such as fungi. Like herbivores and predators, decomposers are heterotrophic, meaning that they use o ...
s.


Role in the environment

Rhizophydiales are parasites of a range of organisms, including invertebrates, other chytrids and algae, and they may have a role in natural control of aquatic populations, especially
phytoplankton Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Ph ...
. One member, '' Rhizophydium graminis'', is a parasite of wheat roots, but causes no extensive damage to the plant. The only documented cases of a chytrid parasitizing vertebrates are ''
Batrachochytrium dendrobatidis ''Batrachochytrium dendrobatidis'' ( ), also known as ''Bd'' or the amphibian chytrid fungus, is a fungus that causes the disease chytridiomycosis in amphibians. Since its discovery in 1998 by Lee Berger, the disease devastated amphibian popul ...
'' and ''
Batrachochytrium salamandrivorans ''Batrachochytrium salamandrivorans'' (''Bsal'') is a pathogenic chytrid fungus that infects amphibian species. Although salamanders and newts seem to be the most susceptible, some anuran species are also affected. ''Bsal'' has emerged recent ...
'', members of this order. They are highly destructive pathogens of frogs and salamanders respectively. The majority of the described saprotrophic species of this order are biodegraders of pollen, with only a few growing on keratin, chitin, and cellulose. The transformational role of the Rhizophydiales in aquatic food webs is little studied but recently more recognized.


Life history

Their thalli (=bodies) consist of two parts: an absorptive branching rhizoidal system that contains no nuclei and a
multinucleate Multinucleate cells (also known as multinucleated or polynuclear cells) are eukaryotic cells that have more than one nucleus per cell, i.e., multiple nuclei share one common cytoplasm. Mitosis in multinucleate cells can occur either in a coordinat ...
sporangium that ranges in shape from spherical, to oval, to pear-shaped, and to multi-lobed. The rhizoids attach the thallus to a substrate (food source) and absorbs nutrients. When the thallus is fully grown, the sporangium releases numerous, unwalled,
uninucleate {{Short pages monitor