Carnivorous fungus

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A fungus of the genus Arthrobotrys, showing adhesive nets which it uses to trap nematodes. Numbered ticks are 122 um apart. 20100828 005957 Fungus.jpg
A fungus of the genus Arthrobotrys , showing adhesive nets which it uses to trap nematodes. Numbered ticks are 122 µm apart.

Carnivorous fungi or predaceous fungi are fungi that derive some or most of their nutrients from trapping and eating microscopic or other minute animals. [1] More than 200 species have been described, belonging to the phyla Ascomycota, Mucoromycotina, and Basidiomycota. They usually live in soil and many species trap or stun nematodes (nematophagous fungus), while others attack amoebae or collembola.

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Fungi that grow on the epidermis, hair, skin, nails, scales or feathers of living or dead animals are considered to be dermatophytes rather than carnivores. Similarly, fungi in orifices and the digestive tract of animals are not carnivorous, and neither are internal pathogens. Neither are insect pathogens that stun and colonize insects normally labelled carnivorous if the fungal thallus is mainly in the insect as does Cordyceps , or if it clings to the insect like the Laboulbeniales. All of these are examples of parasitism or scavenging.

Two basic trapping mechanisms have been observed in carnivorous fungi that are predatory on nematodes:

Sequencing of ribosomal DNA has shown that these trap types occur in separate fungus lineages, [2] an example of convergent evolution.

See also

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Mycology Branch of biology concerned with the study of fungi

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Basidiomycota Division of fungi

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Plant pathology Scientific study of plant diseases

Plant pathology is the scientific study of diseases in plants caused by pathogens and environmental conditions. Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants. Not included are ectoparasites like insects, mites, vertebrate, or other pests that affect plant health by eating of plant tissues. Plant pathology also involves the study of pathogen identification, disease etiology, disease cycles, economic impact, plant disease epidemiology, plant disease resistance, how plant diseases affect humans and animals, pathosystem genetics, and management of plant diseases.

Biological pest control Method of controlling pests using other living organisms

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<i>Verticillium</i> genus of fungi

Verticillium is a genus of fungi in the division Ascomycota, and are an anamorphic form of the family Plectosphaerellaceae. The genus used to include diverse groups comprising saprobes and parasites of higher plants, insects, nematodes, mollusc eggs, and other fungi, thus the genus used to have a wide-ranging group of taxa characterised by simple but ill-defined characters. The genus, currently thought to contain 51 species, may be broadly divided into three ecologically based groups - mycopathogens, entomopathogens, and plant pathogens and related saprotrophs. However, the genus has undergone recent revision into which most entomopathogenic and mycopathogenic isolates fall into a new group called Lecanicillium. The genus now includes the plant-pathogenic species V. dahliae, V. longisporum, V. albo-atrum, V. nubilum, and V. tricorpus.

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Ceratopogonidae A family of flies commonly known as no-see-ums, or biting midges

Ceratopogonidae is a family of flies commonly known as no-see-ums, or biting midges, generally 1–3 mm in length. The family includes more than 5,000 species, distributed worldwide, apart from the Antarctic and the Arctic.

Fungus gnat type of gnat

Fungus gnats are small, dark, short-lived gnats, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae, and Mycetophilidae ; they comprise six of the seven families placed in the superfamily Sciaroidea.

Saccharomycotina subdivision of fungi

Saccharomycotina is a subdivision (subphylum) of the division (phylum) Ascomycota in the Kingdom Fungi. It comprises most of the ascomycete yeasts. The members of Saccharomycotina reproduce by budding and they do not produce ascocarps.

Thigmonasty

Thigmonasty or seismonasty is the nastic response of a plant or fungus to touch or vibration. Conspicuous examples of thigmonasty include many species in the leguminous subfamily Mimosoideae, active carnivorous plants such as Dionaea and a wide range of pollination mechanisms.

Nematophagous fungus Carnivorous fungi specialized in trapping and digesting nematodes

Nematophagous fungi are carnivorous fungi specialized in trapping and digesting nematodes. Around 160 species are known. There exist both species that live inside the nematodes from the beginning and others that catch them, mostly with glue traps or in rings, some of which constrict on contact. Some species possess both types of traps. Another technique is to stun the nematodes using toxins, which is a method employed by Coprinus comatus, Stropharia rugosoannulata, and the family Pleurotaceae. The habit of feeding on nematodes has arisen many times among fungi, as is demonstrated by the fact that nematophagous species are found in all major fungal groups. Nematophagous fungi can be useful in controlling those nematodes that eat crops. Purpureocillium, for example, can be used as a bio-nematicide.

Carnivorous plant plants that trap and consume animals or protozoans

Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants have adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic bogs. Charles Darwin wrote Insectivorous Plants, the first well-known treatise on carnivorous plants, in 1875. Carnivorous plants can be found on all continents except Antarctica, as well as many Pacific islands.

Fungus Kingdom of eukaryotes that includes mushrooms, yeasts, molds and related organisms

A fungus is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, which is separate from the other eukaryotic life kingdoms of plants and animals.

Nematode A phylum of worms with tubular digestive systems with openings at both ends

The nematodes or roundworms constitute the phylum Nematoda, with plant-parasitic nematodes being known as eelworms. They are a diverse animal phylum inhabiting a broad range of environments. Taxonomically, they are classified along with insects and other moulting animals in the clade Ecdysozoa, and unlike flatworms, have tubular digestive systems with openings at both ends. Like tardigrades they have a reduced number of Hox genes, but as their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, it shows that the reduction has occurred within the nematode phylum.

Orbiliaceae family of fungi

The Orbiliaceae are a family of saprobic sac fungi in the order Orbiliales. The family, first described by John Axel Nannfeldt in 1932, contains 288 species in 12 genera. Members of this family have a widespread distribution, but are more prevalent in temperate regions. Some species in the Orbiliaceae are carnivorous fungi, and have evolved a number of specialized mechanisms to trap nematodes.

Forest pathology is the research of both biotic and abiotic maladies affecting the health of a forest ecosystem, primarily fungal pathogens and their insect vectors. It is a subfield of forestry and plant pathology.

<i>Arthrobotrys oligospora</i> species of fungus

Arthrobotrys oligospora was discovered in Europe in 1850 by Georg Fresenius. 'A. oligospora' is the model organism for interactions between fungi and nematodes. It is the most common nematode capturing fungus, and most widespread nematode trapping fungus in nature. It was the first species of fungi documented to actively capture nematodes.

Dactylellina haptotyla is a common soil-living fungus that develops structures to capture nematodes as nutrient source. In the presence of nematodes, spores can germinate into sticky knobs or non-constricting loops. The fungus traps nematodes with sticky knobs and non-constricting loops, then breakdown the cuticle, and penetrates the body of nematodes to obtain nutrients. For its predatory nature, Dactylellina haptotyla is also considered as nematode-trapping fungus or carnivorous fungus.

References

  1. Pramer, D. 1964. Nematode-trapping fungi. Science144: 382–388.
  2. Ahrén, D., M.U. Bjõrn & A. Tunlind 1998. Phylogeny of nematode-trapping fungi based on 18S rDNA sequences. FEMS Microbiology Letters158: 179–184.