Mycorrhizal Fungi: Biodiversity, Ecological Significance, and Industrial Applications

Improved Tolerance of Mycorrhizal Torreya grandis Seedlings to Sulfuric Acid Rain Related to Phosphorus and Zinc Contents in Shoots

“…Meanwhile, a deficiency in P stunts plant growth, resulting in dark green coloration, necrotic spots on the leaves, slender stems, and delayed maturation [ 54 ]. P is the most commonly reported mineral nutrient to be enhanced with mycorrhizal inoculation under stressful conditions [ 23 , 26 , 55 ], which was corroborated in our study but was not noted in previous studies on mycorrhizal sorghum grown in acid soils [ 30 ]. Zinc is an essential micronutrient for chlorophyll biosynthesis in some plants, and Zn deficiencies are characterized by reductions in intermodal growth and by small and distorted leaves with white necrotic spots.…”

“…Notably, in this study, R. irregularis was more efficient at increasing P and Zn 2+ acquisition in T. grandis shoots than other mycorrhizal fungi, which could therefore enhance the yield and nutritional quality of T. grandis nuts in SAR-impacted areas. Numerous studies have confirmed the positive effects of AMF on nutrient uptake and plant quality, which can be considered as an assurance against their deterioration caused by unfavorable factors [ 23 , 57 , 58 ].…”

“…It remains unclear how exactly AMF promote plant performance under unfavorable conditions. Previous studies have suggested that the improvement in nutrient uptake (especially P), increased osmotic protective agents, such as proline, soluble sugars, or amino acids, and/or the enhancement of physiological processes, such as photosynthesis or water absorption capacity, are responsible for the mycorrhizal benefits [ 23 , 63 , 64 ]. In our study, a combination of root colonization, acid tolerance, and the concentrations of shoot-P, shoot-Zn 2+ , and root-Fe 2+ in T. grandis likely worked together to confer mycorrhizal benefits under SAR.…”

“…Arbuscular mycorrhizal fungi (AMF), an important component of soil biota, occur naturally in acidic soils [ 18 , 19 , 20 , 21 ]. Through symbiotic association, fungal partners obtain shelter and fixed carbon from the host plants and in return provide multiple benefits to these plants, such as improved uptake of mineral nutrients, especially phosphorus and other relatively immobile micronutrients such as zinc, magnesium, copper, and calcium, reduced oxidative stress, and maintained water balance, which can positively impact plant growth and improve resistance to abiotic stresses [ 22 , 23 , 24 , 25 ]. Although AMF may be adversely affected by SAR [ 20 , 26 , 27 ], some studies have reported enhanced growth and performance of mycorrhizal plants under SAR conditions [ 28 , 29 , 30 ].…”

Biofertilizers: An ecofriendly technology for nutrient recycling and environmental sustainability

“…Many of these microorganisms within the plant's microbiome play many vital roles in promoting the growth and development of agriculturally important crop plants ( Bakker et al, 2013 ; Bulgarelli et al, 2013 ; Fasusi et al, 2021 ). For screening of efficient beneficial microbial strains for use as biofertilizer, microorganisms isolated from the rhizosphere are screened for plant growth-promoting (PGP) traits along with effective colonization ability (Andreozzi et al, 2019; Pandey et al, 2019 ). Various beneficial properties of PGP microbes for utilization as biofertilizer include decomposition of organic matter, enhancing nutrient availability, production of phytohormones and contribution towards mitigation of abiotic and biotic stresses (Lalitha, 2017; Sehrawat and Sindhu, 2019 ; Zhang et al, 2021 ).…”