Arbuscular mycorrhizal fungi and production of secondary metabolites in medicinal plants

Abstract

Medicinal plants are an important source of therapeutic compounds used in the treatment of many diseases since ancient times. Interestingly, they form associations with numerous microorganisms developing as endophytes or symbionts in different parts of the plants. Within the soil, arbuscular mycorrhizal fungi (AMF) are the most prevalent symbiotic microorganisms forming associations with more than 70% of vascular plants. In the last decade, a number of studies have reported the positive effects of AMF on improving the production and accumulation of important active compounds in medicinal plants.In this work, we reviewed the literature on the effects of AMF on the production of secondary metabolites in medicinal plants. The major findings are as follows: AMF impact the production of secondary metabolites either directly by increasing plant biomass or indirectly by stimulating secondary metabolite biosynthetic pathways. The magnitude of the impact differs depending on the plant genotype, the AMF strain, and the environmental context (e.g., light, time of harvesting). Different methods of cultivation are used for the production of secondary metabolites by medicinal plants (e.g., greenhouse, aeroponics, hydroponics, in vitro and hairy root cultures) which also are compatible with AMF. In conclusion, the inoculation of medicinal plants with AMF is a real avenue for increasing the quantity and quality of secondary metabolites of pharmacological, medical, and cosmetic interest.

Co-Application of TiO2 Nanoparticles and Arbuscular Mycorrhizal Fungi Improves Essential Oil Quantity and Quality of Sage (Salvia officinalis L.) in Drought Stress Conditions

“…Additionally, TiO 2 nanoparticles help to convert inorganic N into organic N in the form of protein and chlorophyll, which leads to an increase in the photosynthetic rate [40]. Zhao et al [41] noted that the increase in primary photosynthesis compounds including erythrose-4-phosphate, phosphoenolpyruvate, pyruvate, and glyceraldehyde-3-phosphate plays a main role in increasing terpene constituents and EO productivity in medicinal and aromatic plants. In addition, Hazzoumi et al [42] concluded that AMF inoculation stimulates the productivity of EO glands probably by increasing endogenous hormone levels, particularly cytokinin, indole-3-acetic acid, and gibberellin.…”

Optimizing Phytochemical and Physiological Characteristics of Balangu (Lallemantia iberica) by Foliar Application of Chitosan Nanoparticles and Myco-Root Inoculation under Water Supply Restrictions

“…On the other hand, the impact of Cs-NPs on dry matter retention during drought stress could be related to the reduction in transpiration induced by the closure of the stomata [18]. Moreover, the inoculation of mycorrhizal fungi with host plant roots improves the plant performance directly through increasing nutrient and water uptake and indirectly by plant phytohormonal secretions of gibberellic acid, cytokinins and jasmonic acid [52]. It was reported that inoculation of mycorrhizal fungi in thyme roots enhanced plant productivity through improving macro-and micro-nutrient uptake under drought stress conditions [14].…”

“…It seems that the co-application of Cs-NPs+ Myco-Root improves the photosynthetic rate, along with the nutrient accessibility, which have an important role in the production of carbohydrates and also in the development of glandular trichomes, EO channels and secretory ducts [13]. In this situation, the higher photosynthetic rate enhances the concentration of primary metabolites such as pyruvate, erythrose-4-phosphate, phosphoenolpyruvate and glyceraldehyde-3-phosphate, which are used as precursors in the synthesis of EO constituents [52].…”

Arbuscular Mycorrhizal Symbiosis: A Strategy for Mitigating the Impacts of Climate Change on Tropical Legume Crops

“…Furthermore, AMF can furnish host plants with vital inorganic nutrients, resulting in increased growth and yield under both unstressed and stressed conditions [ 19 ]. Despite their enormous potential to improve plant growth under climatic stresses, little is known about how AMF-induced modulations in tolerance mechanisms, as well as the crosstalk triggered to regulate plant performance, can help increase crop productivity [ 24 , 25 ], especially for the majority of previously overlooked leguminous species.…”