Abstract
Soil salinization poses an escalating threat to global maize (Zea mays L.) production, particularly in arid and semi-arid regions reliant on hypersaline irrigation water. Arbuscular mycorrhizal fungi (AMF) offer a sustainable biological strategy to ameliorate salt-induced physiological constraints. This study evaluated the efficacy of a native AMF consortium, comprising Rhizophagus intraradices and Funneliformis mosseae isolated from saline soils, in mitigating oxidative stress and enhancing phosphorus (P) nutrition in Zea mays subjected to saline irrigation (150 mM NaCl). Inoculated plants exhibited high root colonization (68%) and a significant restoration of shoot dry biomass (42% higher than non-inoculated salt-stressed controls). AMF colonization markedly enhanced total P accumulation by 58% and upregulated the expression of the mycorrhizal-specific phosphate transporter gene ZmPT6. Furthermore, mycorrhizal plants demonstrated superior reactive oxygen species (ROS) detoxification, characterized by a 35% reduction in malondialdehyde (MDA) levels alongside significantly elevated activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). Electrolyte leakage was reduced by 28%, preserving cellular membrane integrity and leaf relative water content. These findings demonstrate that native AMF strains confer robust physiological protection against hypersalinity by integrating enhanced P acquisition with augmented enzymatic antioxidant defenses, highlighting their potential as effective bio-inoculants for sustainable maize production in salt-affected agricultural ecosystems.
