Opinion Article, J Plant Physiol Pathol Vol: 11 Issue: 3
Nutritional Functions of Mycorrhizal Symbiosis in Plants
Chen Ken Wang*
Received date: 24 April, 2023, Manuscript No. JPPP-23-101142;
Editor assigned date: 28 April, 2023, Pre QC No. JPPP-23-101142(PQ);
Reviewed date: 15 May, 2023, QC No. JPPP-23-101142;
Revised date: 23 May, 2023, Manuscript No. JPPP-23-101142 (R);
Published date: 31 May, 2023, DOI: 10.4172/2329-955X.1000298
Citation: Wang CK (2023) Nutritional Functions of Mycorrhizal Symbiosis in Plants. J Plant Physiol Pathol 11:3.
Mycorrhizal symbiosis is a mutually beneficial association between certain plant species and specialized fungi known as mycorrhizae. This symbiotic relationship plays a crucial role in plant nutrition, enhancing the uptake of nutrients from the soil and promoting plant growth and development. Mycorrhizal fungi extend the root system of plants, increasing their ability to access nutrients such as phosphorus and nitrogen. In return, the fungi receive carbohydrates and other organic compounds from the plant. In this article, we will explore the role of mycorrhizal symbiosis in plant nutrition, focusing on the types of mycorrhizae, the mechanisms of nutrient exchange, and the benefits for both the plant and the fungus. There are several types of mycorrhizae, but the two most common types are Arbuscular Mycorrhizae (AM) and Ecto Mycorrhizae (EM). Arbuscular mycorrhizae are formed by fungi from the Glomeromycota phylum, while ectomycorrhizae involve fungi from various phyla, including Basidiomycota and Ascomycota.
Arbuscular mycorrhizae penetrate the plant root cells, forming intricate structures called arbuscules, which provide a large surface area for nutrient exchange. These mycorrhizae are widespread in most plant species and are particularly effective in enhancing phosphorus uptake. Ectomycorrhizae, on the other hand, form a sheath-like structure around the plant roots, extending into the soil but not penetrating the root cells. These mycorrhizae are commonly found in woody plants, such as trees and shrubs, and are important for nutrient uptake, especially in nutrient-poor environments.
Mycorrhizal symbiosis enhances plant nutrition through various mechanisms of nutrient exchange. One of the key benefits is the increased uptake of phosphorus, an essential nutrient for plant growth. Mycorrhizal fungi have the ability to access phosphorus in the soil that is otherwise unavailable to plants. The extensive fungal hyphae extend into the soil, effectively exploring a larger volume of soil, increasing the surface area for nutrient absorption. The fungi release enzymes that break down organic phosphorus compounds, converting them into a form that plants can readily absorb.
In addition to phosphorus, mycorrhizal symbiosis also facilitates the uptake of other nutrients, such as nitrogen, potassium, and micronutrients. The fungal hyphae can transport these nutrients over longer distances than plant roots alone, effectively expanding the nutrient uptake zone of the plant. The fungi have high affinity transporters that facilitate the absorption and transfer of nutrients from the soil to the plant roots.
Furthermore, mycorrhizal fungi play a crucial role in improving soil structure and nutrient cycling. The fungal hyphae form a dense network that binds soil particles, creating aggregates that improve soil porosity, water retention, and aeration. This contributes to enhanced root growth and nutrient availability. The fungi also have the ability to release organic acids and enzymes that mobilize nutrients from organic matter in the soil, making them more accessible to plants.
Mycorrhizal symbiosis provides several benefits for both the plant and the fungus involved in the association. For the plant, mycorrhizal symbiosis enhances nutrient uptake and nutrient use efficiency, allowing plants to thrive in nutrient-limited environments. The increased availability of phosphorus, nitrogen, and other nutrients contributes to improved plant growth, development, and overall productivity. Plants with mycorrhizal associations often exhibit increased biomass, larger root systems, and enhanced resistance to stresses such as drought and disease. Mycorrhizal symbiosis also plays a role in plant defense mechanisms. The association can induce the plant's systemic resistance, making it more resistant to pathogenic fungi and other pathogens. The presence of mycorrhizal fungi can trigger the plant's immune response and the production of defense compounds, enhancing the plant's ability to fend off diseases.
For the fungus, mycorrhizal symbiosis provides a source of carbohydrates and other organic compounds from the plant. The plant supplies the fungus with photosynthetically produced sugars, which serve as an energy source for the fungal growth and reproduction. In return, the fungus enhances the plant's nutrient acquisition capabilities, creating a mutually beneficial relationship. Furthermore, mycorrhizal fungi can improve their own survival and dispersal through the association with plants. The extensive fungal mycelium provides an extended exploration network in the soil, increasing the chances of encountering suitable host plants and expanding their range. The formation of spores by the fungi allows them to disperse to new areas, colonizing the roots of other plants and establishing new symbiotic relationships.