Potential of Native Arbuscular Mycorrhizal Fungi, Rhizobia, and/or Green Compost as Alfalfa (Medicago sativa) Enhancers under Salinity

Abstract

Salinity is one of the devastating abiotic stresses that cause reductions in agricultural production. The increased salinization affects alfalfa growth, metabolism, and rhizobium capacity for symbiotic N2 fixation negatively. This study was undertaken to investigate the efficiency of green compost (C; made from green waste), arbuscular mycorrhizal fungi (M; field-sourced native consortium), and/or rhizobium (R; a salt-tolerant rhizobium strain) individually or in combination as an effective strategy to improve alfalfa productivity under non-saline and high-saline (120 mM NaCl) conditions. In addition, we aimed to understand the agro-physiological and metabolic basis as well as glomalin content in the soil of biofertilizers-induced salt tolerance in alfalfa. Here, we show that mycorrhizal infection was enhanced after MR inoculation, while C application decreased it significantly. Salinity reduced growth, physiological functioning, and protein concentration, but the antioxidant system has been activated. Application of the selected biofertilizers, especially C alone or combined with M and/or R improved alfalfa tolerance. The tri-combination CMR mitigated the negative effects of high salinity by stimulating plant growth, roots and nodules dry matters, mineral uptake (P, N, and K), antioxidant system, synthesis of compatible solutes, and soil glomalin content, sustaining photosynthesis-related performance and decreasing Na+ and Cl- accumulation, lipid peroxidation, H2O2 content, and electrolyte leakage.

Effect of co-inoculation with arbuscular mycorrhizal fungi and phosphate solubilizing fungi on nutrient uptake and photosynthesis of beach palm under salt stress environment

“…1 ). The inhibitory effects of salt stress on shoot growth were greater than those on root growth (Table 1 ), which is consistent with Qiu et al 11 and Ben-Laouane et al 26 but not with Ait-El-Mokhtar et al 17 Salt stress had different effects on the root and shoot growth of different sweet sorghum varieties 10 . Is the varying sensitivity of the roots and stems of different plants to stress related to their particular mechanisms of coping with stress?…”

The Native Arbuscular Mycorrhizal Fungi and Vermicompost-Based Organic Amendments Enhance Soil Fertility, Growth Performance, and the Drought Stress Tolerance of Quinoa

“…However, to facilitate the widespread adoption of these technologies in agriculture, their potential and reliability need to be validated in the field to ensure that they remain affordable and more effective than the existing approaches. Previous studies demonstrated the role of AMF on drought and salt stress mitigation in alfalfa, date palm, and carob plants [ 44 , 45 , 46 ]. However, the role of native AMF in combination with vermicompost on alterations in ROS scavenging machinery, to impart tolerance against field drought stress, has not yet been studied.…”

“…Under DS, quinoa plants inoculated with AMF accumulated higher proteins and sugar content, likely to maintain high hydration and turgor levels and to maintain the overall physiological traits [ 95 , 116 ]. In addition, the higher content of soluble proteins in inoculated and amended plants may explain the strengthening of the enzymatic antioxidant defense system under abiotic stress [ 28 , 45 , 46 ].…”

Multiple Potential Plant Growth Promotion Activities of Endemic Streptomyces spp. from Moroccan Sugar Beet Fields with Their Inhibitory Activities against Fusarium spp.

“…In contrast to the well-documented action of phosphate-solubilizing and nitrogen-fixing microorganisms in plant P and N nutrition [ 13 , 14 ], the importance of microbial activity on plant K nutrition is less well understood. It has been shown that bacteria and mycorrhizal fungi do solubilize mineral K by various mechanisms such as production of alkaline substances including ammonia and other metabolites upon death of microbial cells and subsequent proteolysis [ 15 , 16 ]. K-solubilizing bacteria (KSB) have attracted more attention because of their ability to increase plant growth and yield [ 17 ].…”