Influence of Mycorrhizal Fungi on Sugar Beet growth, Nutrient Use Efficiency, Defense Responses, and Soil Microbial Dynamics

Sugar beet (Beta vulgaris ssp. Vulgaris) is a globally significant crop, ranking second after sugarcane in sugar production. Egypt, a leading producer, derives a substantial portion of its sugar from sugar beet cultivation, emphasizing its economic importance. Despite its popularity, sugar beet faces various challenges, including abiotic and biotic stresses, which adversely affect both yield and quality. Excessive use of chemical fertilizers has been reported to cause soil and water pollution, negatively impacting crop yields. This study investigated the impact of arbuscular mycorrhizal fungi (AMF), a type of beneficial soil fungus, on sugar beet growth and productivity. AMF form symbiotic relationships with plants, enhancing nutrient uptake, improving water use efficiency, and promoting plant health. Through a greenhouse experiment, this study investigated the impact of AMF on sugar beet vegetative growth, plant nutrient uptake, phosphors bioavailability from rock phosphate (RP) source, root biomass, plant defense genes expression, soil bacterial and fungal community alterations, it was demonstrated that AMF significantly influenced sugar beet growth, nutrient acquisition, and sugar production. Specifically, AMF-inoculated sugar beets exhibited increased root development, enhanced nutrient uptake of essential elements 37 % for phosphorus from RP and 24 % for nitrogen, and about 39%, 58% increasing in root diameter and fresh weight a substantial 17 % increase in sugar yield compared to non-inoculated controls.