Introduction about Mycorrhizal Fungi

A mycorrhiza is a mutual symbiotic association between a fungus and a plant. In other words, Mycorrhizas are fungal associations between plant roots and beneficial fungi.

The synergy of mycorrhiza serves the following way.

Mycorrhizas grow in association with plant roots, and exist by taking sugars from plants ‘in exchange’ for moisture and nutrients gathered from the soil by the fungal strands. As a result, the mycorrhizas greatly increase the absorptive area of a plant, acting as extensions to the root system.

The term mycorrhiza refers to the role of the fungus in the plant’s rhizosphere, its root system. Mycorrhizae play important roles in plant nutrition, soil biology, and soil chemistry.

At the same time, it is important to highlight that the fungi effectively extend the root area of plants and are extremely important to most wild plants. However, the importance of mycorrhizal fungi is less significant for garden plants because the use of fertilisers and cultivation disrupts and replaces these associations.

What is Arbuscular Mycorrhizal Fungi?

Arbuscular mycorrhizal (AM) fungi is a symbiosis between plants and members of an ancient phylum of fungi, the Glomeromycota. It improves the supply of water and nutrients, such as phosphate and nitrogen, to the host plant. This fungus are widely recognized as the oldest and most widespread plant symbionts which occur in the soil of most ecosystems.

After millions of years of evolving with plants, AM fungi still are essential associates of many plants and play an important role in absorbing nutrients, regulating development, and enhancing plant resistance and tolerance to environmental stresses.

Importantly, up to 20% of plant-fixed carbon is transferred to the fungus.

If mycorrhization of roots is by any reason declined or not formed, plant productivity will be negatively affected.

The hyphae of the fungi act as extend root system with several times larger than root only, which helps roots to reach deeper and wider in soils to seek water and food. When colonize to plant roots, AM will form special structures (intraradical hyphae, arbuscules, vesicules) inside root cells for nutrient exchange.

Plants provide the fungi carbohydrates, and in turn, fungi support plants more water and minerals uptake from soils by their widespread hyphae.

Importance of Arbuscular Mycorrhizal Fungi as biofertilizer

Arbuscular Mycorrhizal Fungi constitute a group of root obligate biotrophs that exchange mutual benefits with about 80% of plants.

AM are considered natural biofertilizers, since they provide the host with water, nutrients, and pathogen protection, in exchange for photosynthetic products. Thus, AM are primary biotic soil components which, when missing or impoverished, can lead to a less efficient ecosystem functioning.

The process of re-establishing the natural level of AM richness can represent a valid alternative to conventional fertilization practices, with a view to sustainable agriculture.

The main strategy that can be adopted to achieve this goal is the direct[ re-introduction] (https://doi.org/10.3389/fmicb.2015.01559) of AMF propagules (inoculum) into a target soil. Originally, AMF were described to generally lack host- and niche-specificity, and therefore suggested as agriculturally suitable for a wide range of plants and environmental conditions. Unfortunately, the assumptions that have been made and the results that have been obtained so far are often worlds apart.

Issues on the response to the same AMF species mix

The problem is that success is unpredictable since different plant species vary their response to the same AMF species mix. Many factors can affect the success of inoculation and AMF persistence in soil, including species compatibility with the target environment, the degree of spatial competition with other soil organisms in the target niche and the timing of inoculation.

Thus, it is preferable to take these factors into account when “tuning” an inoculum to a target environment in order to avoid failure of the inoculation process. Genomics and transcriptomics have led to a giant step forward in the research field of AMF, with consequent major advances in the current knowledge on the processes involved in their interaction with the host-plant and other soil organisms.

The history of AMF applications in controlled and open-field conditions is now long. A review of biofertilization experiments, based on the use of AMF, has here been proposed, focusing on a few important factors that could increase the odds or jeopardize the success of the inoculation process.

Different types of Mycorrhyzal Fungi

[Estimates] (https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.13288) suggest that there are c. 50 000 fungal species that form mycorrhizal associations with c. 250 000 plant species. The development of high-throughput molecular tools has helped us to better understand the biology, evolution, and biodiversity of mycorrhizal associations. Nuclear genome assemblies and gene annotations of 33 mycorrhizal fungal species are now available providing fascinating opportunities to deepen our understanding of the mycorrhizal lifestyle, the metabolic capabilities of these plant symbionts, the molecular dialogue between symbionts, and evolutionary adaptations across a range of mycorrhizal associations.

Four major mycorrhizal types have been described based on their structure and function, namely arbuscular mycorrhiza (AM), ectomycorrhiza (EM), orchid mycorrhiza and ericoid mycorrhiza.

Mycorrhizal associations are extremely abundant in the plant kingdom.

Estimates suggest that c. 74% of all plant species form AMs with fungi of the Glomeromycota clade (Smith & Read, 2008; Brundrett, 2009), c. 2% of plants form EM associations, c. 9% of plants form orchid mycorrhizas and c. 1% of plants form ericoid mycorrhizas (Brundrett, 2009). Some plant species, such as poplars and eucalypts, also form dual symbiotic associations (e.g. with AM and EM fungi; Egerton-Warburton & Allen, 2001; Villarreal-Ruiz et al., 2004). Almost all ecosystems are dominated by mycorrhizal plants (Read, 1991) with the exception of early successional communities, intensively managed arable fields and extremely P-impoverished soils that are dominated by with plants with cluster roots (Lambers et al., 2008).

Basics about Medicinial Plants

Medicinal plants have been used in healthcare since time immemorial. Studies have been carried out globally to verify their efficacy and some of the findings have led to the production of plant-based medicines.

A medicinal plant is any plant which, in one or more of its organs, contains substances that can be used for therapeutic purposes or which are precursors for the synthesis of useful drugs. This description makes it possible to distinguish between medicinal plants whose therapeutic properties and constituents have been established scientifically, and plants that are regarded as medicinal but which have not yet been subjected to a thorough scientific study.

A number of plants have been used in traditional medicine for many years. Some do seem to work although there may not be sufficient scientific data (double-blind trials, for example) to confirm their efficacy. Such plants should qualify as medicinal plants. The term ‘crude drugs of natural or biological origin’ is used by pharmacists and pharmacologists to describe whole plants or parts of plants which have medicinal properties. A definition of medicinal plants should include the following (Sofowora 2008; Evans, 2008):

• plants or plant parts used medicinally in galenical preparations (e.g. decoctions, infusions, etc.) e.g. Cascara bark;
• plants used for extraction of pure substances either for direct medicinal use or for the hemi-synthesis of medicinal compounds (e.g. hemi-synthesis of sex hormones from diosgenin obtained from Dioscorea yams);
• food, spice, and perfumery plants used medicinally, e.g. ginger;
• microscopic plants, e.g. fungi, actinomycetes, used for isolation of drugs, especially antibiotics. Examples are ergot (Claviceps purpurea growing on rye) or Streptomyces griseus; and fibre plants, e.g. cotton, flax, jute, used for the preparation of surgical dressings.

What is Ehretia asperula?

According to the findings of Korean scientists, Ehretia asperula plant is endemic to Northern Vietnam. E asperula leaves have traditionally been used as a folk medicine to treat a variety of ailments such as hepatitis, liver cirrhosis, and cancer. Furthermore, E asperula prevents or alleviates diabetes, hypertension, and acne. Some researchers have recently revealed the potential pharmacological effects of E asperula in cancer treatment, but there are no trial results using E asperula in cancer therapy.

One study identified that the leaves of E asperula contained several constituents with anti-cancer properties, but the underlying mechanisms responsible for these effects are unknown. Only a few reports to date have characterized the chemical components of this plant and their biological effects, particularly on eye disease.

Solanum Procumben: Benefits for Health

Solanum is a genus which belongs to Solanaceae family, includes many species of cropsor medicinal plants as eggplant, tomato, potato, twoleaf nightshade, etc. Number of species are used as medicinal herbs of Solanum genus in Vietnam is up to 41, one of those is Solanum procumbens Lour., which is often used to treat hepatitis or cirrhosis. The needs of planting this plant is rising up.

Experiment settings for Medicinial Plants

How does Petiole Pro help in mycorrhizal fungus research

Conclusions

References