John Miller
Mycorrhizae are a type of fungus that forms a symbiotic relationship with plants, aiding in the exchange of nutrients between the host plant and the soil. The two main types of mycorrhizae are ectomycorrhizae and endomycorrhizae, differentiated by whether or not they penetrate the cell wall of the plant's root. Endomycorrhizae, the focus of this article, are those that do penetrate the cell wall. Endomycorrhizal fungi benefit a large number of plants, particularly in areas with poor soil and drought conditions, by increasing the surface area of the plant's root system and aiding in the uptake of water and nutrients.
| Characteristics | Values |
|---|---|
| Definition | Endomycorrhizae are a type of mycorrhizae, which are a symbiotic association between a green plant and a fungus. |
| Hyphae Location | Hyphae of endomycorrhizae penetrate the cell wall and invaginate the cell membrane. |
| Nutrient Exchange | Endomycorrhizae facilitate the exchange of nutrients between the host plant and the soil. They aid in the uptake of water, inorganic phosphorus, mineral or organic nitrogen, and amino acids. |
| Plant Species | Endomycorrhizae are associated with approximately 85% of the world's plant species, including orchids, herbs, shrubs, and trees. |
| Benefits | Endomycorrhizae increase the surface area of the plant's root system, providing an advantage in areas with drought or nutrient-poor soil. They also offer some protection to the roots. |
| Types | Arbuscular, ericoid, arbutoid, monotropoid, and orchid mycorrhizas are considered endomycorrhizae. |
| Application | Endomycorrhizae can be applied to plants through direct infection, incorporation into media or soil, or irrigation. |
Explore related products
What You'll Learn
Arbuscular mycorrhizae
AM is a symbiosis between plants and fungi, with the fungi belonging to the Glomeromycota phylum. The fungi induce a signal transduction process in root cells, which involves the induction and decoding of calcium signatures. The symbiosis improves the supply of water and nutrients, such as phosphate and nitrogen, to the host plant. In exchange, up to 20% of plant-fixed carbon is transferred to the fungus.
When AM fungal hyphae encounter the root of a host plant, an 'infection structure' called an appressorium forms on the root epidermis. The hyphae can then penetrate the host's parenchyma cortex, forming highly branched structures called arbuscules. These arbuscules are the distinguishing structures of arbuscular mycorrhizal fungus. They are formed inside the cell wall but outside the plasma membrane, providing a large surface area for the exchange of nutrients.
AM fungi exhibit host-specific chemotaxis, which enables hyphal growth toward the roots of a potential host plant. Molecular techniques have been used to understand the signalling pathways between AM fungi and plant roots. This signalling involves the exchange of strigolactones and 'Myc factors' between the symbionts.
Mushrooms and Yeast Infections: What's the Connection?
You may want to see also
Orchid mycorrhizae
The orchid family relies on mycorrhizae for seed germination, nourishment, growth and development. Orchid seeds will not germinate until they have formed an association with a mycorrhizal fungus. The fungus enters the orchid embryo, producing intracellular hyphal coils called pelotons, which are a defining anatomical structure of orchid mycorrhizae. The pelotons provide a large surface area for the exchange of nutrients between the orchid and the fungus. The major function of orchid mycorrhizae is nutrient acquisition, including water, inorganic phosphorus, mineral or organic nitrogen, and amino acids. In exchange, the orchid provides the mycorrhizae with carbon. This symbiotic relationship benefits both organisms, particularly in areas where drought or nutrient-poor soil are common, as the larger surface area of the root system allows plants with mycorrhizal relationships to outcompete for nutrients.
The fungi that form orchid mycorrhizae are typically basidiomycetes, including Ceratobasidium (Rhizoctonia), Sebacina, Tulasnella and Russula species. Most orchids associate with saprotrophic or pathogenic fungi, while some associate with ectomycorrhizal fungal species, forming tripartite associations with the orchid and its photosynthetic host plant. The reliance of orchids on specific fungi has been widely studied, and modern research has found that the germination of orchids may be more successful with certain fungi. The application of modern biotechnological approaches has also resolved many controversial issues and improved the quality of flowers.
The significance of orchid mycorrhizae for seed germination, nourishment, growth promotion and survival has been recognised for over a century, but understanding the mode of interaction between orchids and mycorrhizae remains a major challenge in ecology and evolutionary biology. Orchid mycorrhizae have unique and specialised nutrient transfer interactions, which define the fitness and diversity of the orchid family.
Keep Mushrooms Fresh: Best Storage Practices
You may want to see also
Ericoid mycorrhizae
The fungi involved in ericoid mycorrhizae are primarily Ascomycota, but Basidiomycota are also recognised as frequent associates of ericoid roots. The symbiosis enables plants to better adapt to adverse soil conditions, enhances plant tolerance to abiotic and biotic stresses, and improves plant growth and establishment. For example, ericoid mycorrhizae can aid in the uptake of nitrogen and phosphorus, as well as help regulate the acquisition of iron, manganese, and aluminium ions, which are often present in highly available forms in acidic soils.
Ericoid mycorrhizal fungi are characterised by the formation of distinctive hyphal coils within the root cells of their plant partners. These coils are formed in the epidermal cells of the fine hair roots of ericaceous species. The coils are the site of nutrient exchange between the plant and the fungus. Evidence suggests that these coils only function for a few weeks before the plant cell and fungal hyphae begin to degrade.
Mushroom Adaptogens: Safe Superfood or Health Risk?
You may want to see also
Explore related products
Arbutoid mycorrhizae
Mycorrhizae are symbiotic associations between a fungus and a plant. The term mycorrhiza refers to the role of the fungus in the plant's rhizosphere, or root system and its surroundings. Mycorrhizae play important roles in plant nutrition, soil biology, and soil chemistry.
Endomycorrhizae are those that penetrate the cell wall of the plant's root. Endomycorrhizae facilitate the exchange of nutrients between the host plant and the soil. They aid in the uptake of water, inorganic phosphorus, mineral or organic nitrogen, and amino acids. In exchange for providing these nutrients, the plant provides the mycorrhizae with carbon. This relationship benefits both organisms, especially in areas where drought is common or the soil is nutrient-poor.
The arbutoid mycorrhizal association is similar to ectomycorrhizae in structure and function. It involves a thin fungal sheath surrounding the outside of the root, a paraepidermal Hartig net consisting of fungal penetration between the epidermis, and outer layer of cortical cells into which the hyphae invade to form hyphal coils (intracellular hyphal complexes). There is an exchange of nutrients and photosynthates between arbutoid plants and adjacent tree species. The Hartig net is named after Robert Hartig, who conducted early research on the anatomy of the interface between symbionts.
Golden Oyster Mushrooms: Hallucinogenic or Not?
You may want to see also
Monotropoid mycorrhizae
Structurally, monotropoid mycorrhizae exhibit features similar to both ectomycorrhizas and ectendomycorrhizas. They are characterised by a thick mantle, a Hartig net confined to the epidermis, and the presence of fungal pegs. The fungal pegs are unique structures that invade the epidermal cells of the host plant, originating from the Hartig net or inner mantle.
Monotropoid mycorrhizal associations are commonly found in forest environments, where the monotropoid plants act as epiparasites on neighbouring trees or shrubs. This means that they indirectly "parasitize" the surrounding trees by relying on the shared fungal network for their nutrient needs. The fungal partners in this association include species from the Boletus genus, connecting the monotropoid plants with their neighbouring trees.
The study of monotropoid mycorrhizae contributes to our understanding of plant-fungal interactions and the evolution of mycorrhizal relationships. Research has revealed that each plant genus or species within the Monotropoideae clade has developed a high degree of specialisation in terms of its fungal associates. This highlights the complex and fascinating dynamics of monotropoid mycorrhizal associations.
Overall, monotropoid mycorrhizae represent a unique form of endomycorrhizal symbiosis, showcasing the diverse ways in which plants and fungi have evolved to interact and mutually benefit each other.
Auri Mushroom Gummies: Legit or a Scam?
You may want to see also
Frequently asked questions
Endomycorrhizas are a type of mycorrhiza, or symbiotic association between a green plant and a fungus. Endomycorrhizas are characterised by the fact that the hyphae of the fungus penetrate the cell wall and invaginate the cell membrane.
There are several types of endomycorrhizas, the most common being arbuscular mycorrhiza (AM). Other types include ericoid, orchid, arbutoid, and monotropoid.
Endomycorrhizas facilitate the exchange of nutrients between the host plant and the soil. They aid in the uptake of water, inorganic phosphorus, mineral or organic nitrogen, and amino acids. This relationship benefits both organisms, as the plant in turn provides the mycorrhiza with carbon.
Endomycorrhizal fungi can colonise plants from three main sources of inoculum: spores, colonised root fragments, and vegetative hyphae. To colonise plant roots, these inoculants, or "propagules", must be present in the substrate and in close proximity to actively growing roots of a compatible plant.
