Role played by arbuscular mycorrhizal fungi in amelioration of salinity stress: a review

BackgroundOne of the most severe environmental factors that limit plant growth and productivity is salinity. Negative impacts od salnity are mostly observed in plants, particularly in coastal or arid regions where soil salinity is high or where irrigation practices introduce excessive salt into the soil. Therefore, understanding the processes that facilitate plant growth in saline environments is essential.ObjectiveA combination of strategies to reduce salt levels in the soil and improve plant tolerance are used to mitigate salinity stress. Known as bio-ameliorators of salt stress, arbuscular mycorrhizal fungi (AMF) shield host plants from the negative effects of salinity.ResultsSome positive consequences include increased nutrition for the host plant, increased K+/Na+ ratios, and a good osmotic adjustment through the accumulation of suitable solutes like glycine betaine, proline, or soluble carbohydrates. Under salt stress, mycorrhizal (M) plants exhibit improved photosynthesis and water use efficiency as compared to non-mycorrhizal (NM) plants. The use of AMF is an environmentally friendly way of increasing agricultural productivity.ConclusionIn this review, significant results of AMF symbiosis on plant biomass, mineral nutrition, osmolytes accumulation, antioxidant defense system and other important physiological processes under salt stress are discussed in detail exploring how AMF increases the salt tolerance of host plants. It provides a thorough, current understanding of AMF and its effects on host plants at various stages of growth most commonly the vegetative growth stages. Additionally, it provides important data for the improvement and advancement of future research activities.