Ectomycorrhizae and Endomycorrhizae

The most well-known symbiotic fungus is those that develop mycorrhizal associations and those that generate lichens by forming partnerships with algae. A significant number of fungi infect plant roots by developing a mycorrhizal relationship with the plants. This relationship is distinct from typical root infection, which is the cause of root illnesses. Mycorrhiza is a non-disease-causing relationship in which a fungus infiltrates the root and absorbs nutrients. Mycorrhizal fungi develop a mutualistic parasitism in which both the plant and the fungus profit from the relationship. Around 90% of terrestrial plants rely on mycorrhizal fungi for mineral nutrients (e.g., phosphorus), and the fungus gets nutrients generated by the plant in exchange. During the winter, when the days are shorter and the amount of light available is decreased, certain plants generate little or no nutrients and must rely on fungus for sugars, nitrogenous compounds, and other nutrients that the fungi may take from waste items in the soil. A fungus can keep its plant host alive by sharing the compounds it takes from the soil with it. The soil in certain lowland forests is rich in mycorrhizal fungi, resulting in mycelial networks that link the trees together.

ECTOMYCORRHIZAE AND ENDOMYCORRHIZAE

Ectomycorrhiza: Woody plants such as birch, beech, willow, pine, oak, spruce, and fir tend to create reciprocal symbiotic associations with Ectomycorrhiza. The Hartig Net is an intercellular surface that defines ectomycorrhizal interactions. The Hartig Net is a network of hyphae that connects epidermal and cortical root cells. The growth of a thick hyphal sheath encircling the root’s surface can also be used to identify ectomycorrhizal. The mantle is the term for this. In other words, ectomycorrhizae exclusively live on the root’s surface. Only 5-10% of terrestrial plant species have ectomycorrhizal fungi.

The fungal network has been proven to transport nutrients between plants. Carbon has been observed moving from paper birch trees to Douglas-fir trees, encouraging ecological succession. Laccaria bicolor, an ectomycorrhizal fungus, has been discovered to attract and kill springtails in order to collect nitrogen, which may subsequently be passed to the mycorrhizal host plant.

Ecto-mycorrhizal associations are formed by a variety of forest trees, including conifers such as Pinus, Cedrus, and Abies, as well as deciduous non-conifers such as oak, beech, and birch. Different types of fungus, usually higher fungi, make up the fungal components. Agarics and gasteromycetes are common basidiomycetes. Ascomycetes truffles have the ability to form associations with pine trees. Members of the genera Russula, Clitocybe, Boletus, Lactarius, Tuber, and others are common ecto-mycorrhizal fungi.

Endomycorrhiza: Endomycorrhizae, on the other hand, are present in over 80% of existing plant species, including most vegetables, grasses, flowers, and fruit trees, as well as crops and greenhouse plants. Endomycorrhizal connections are defined by the fungi’s penetration of the cortical cells and the development of arbuscules and vesicles in the cortical cells. Endomycorrhizae have an exchange mechanism on the interior of the root, with the fungi’s hyphae reaching outside of the root. In comparison to the ectomycorrhizal, it is a more invasive connection.

EXAMPLES OF ECTOMYCORRHIZAE

Basidiomycota: Basidiomycota is one of two great divisions that make up the subkingdom Dikarya (commonly referred to as the “upper fungi ”) within the kingdom Fungi, along with Ascomycota. Basidiomycetes are the members of this fungus. Mushrooms, puffballs, stinkhorns, bracket fungus, other polypore, jelly fungi, boletes, chanterelles, earth stars, smuts, bunts, rusts, mirror yeasts, and Cryptococcus, the human pathogenic yeast, are all classified as Basidiomycota. Except for basidiomycota-yeast, basidiomycota are filamentous fungi that reproduce sexually by forming specialized club-shaped end cells called basidia, which ordinarily carry external mesopores (usually four). Basidiospores are these specialized spores. Some Basidiomycota, on the other hand, are obligatory asexual reproducers.

Ascomycota: It is a phylum of the kingdom Fungi that forms the subkingdom Dikarya with the Basidiomycota. Sac fungi or ascomycetes are the popular names for its members. With approximately 64,000 species, it is the biggest phylum of Fungi.  The “ascus “‘sac, a tiny sexual structure in which nonmotile spores termed ascospores are produced, is the characteristic feature of this fungus group. Some Ascomycota species, however, are asexual, meaning they lack a sexual cycle and so do not produce asci or ascospores. Morels, truffles, brewer’s yeast and baker’s yeast, dead man’s fingers, and cup fungus are all examples of sac fungi. The majority of lichens (loosely referred to as “ascolichens’ ‘), including Cladonia, have fungal symbionts that belong to the Ascomycota.

EXAMPLES OF ENDOMYCORRHIZAE

Ericaceous Mycorrhizae: Ericaceous mycorrhizae can be found on plants in the Ericales order and in acidic, unfriendly conditions. Ericoid mycorrhiza does not produce arbuscules, despite the fact that it penetrates and invaginates the root cells. They do, however, aid in the plant’s mineral acquisition, such as iron, manganese, and aluminum. Outside of the root cells, mycorrhizal fungi create hyphal coils, which dramatically increase root volume.

Arbutoid Mycorrhiza: Arbutoid mycorrhizae are endomycorrhizal fungi that resemble ectomycorrhizal fungi in appearance. They create a fungal sheath around the plant’s roots, but the arbutoid mycorrhiza’s hyphae enter the cortical cells of plant roots, distinguishing it from ectomycorrhizal fungi.

Orchid Mycorrhiza: Certain orchids are unable to photosynthesize until they reach the seedling stage. Other orchids are completely photon-deficient. For at least a portion of their existence, all orchids, however, rely on the sugars given by their fungal companion. Orchid seeds require fungal invasion to germinate since seedlings cannot obtain enough nutrients to thrive on their own. The orchid parasitizes the fungus that infects its roots in this interaction. The hyphae of orchidaceous mycorrhiza penetrate the root’s cells and generate hyphal coils, or pelotons, which are nutrient exchange sites, after the seed coat ruptures and roots begin to emerge.

CONCLUSION

Hence it can be concluded that the most well-known symbiotic fungus is those that develop mycorrhizal associations and those that generate lichens by forming partnerships with algae. A significant number of fungi infect plant roots by developing a mycorrhizal relationship with the plants. This relationship is distinct from typical root infection, which is the cause of root illnesses.