Halophytes-associated endophytic fungi for sustainable development

Halophytes, naturally adapted to survive and grow under high-salinity conditions, harbour complex internal microbiomes composed of endophytic microorganisms that persist within plant tissues without causing disease. Among these, endophytic fungi play a crucial role in enhancing host plant growth and stress tolerance. Halophytes host a diverse community of endophytic fungi that are naturally adapted to extreme saline and arid environments. These fungi establish symbiotic associations with their host plants, improving plant performance and contributing to ecosystem services, thereby making them valuable for sustainable agriculture and environmental management. In agricultural systems, these endophytes promote plant growth and yield by producing phytohormones, solubilizing nutrients, and activating stress-protective pathways. They further enhance tolerance to salinity and drought by maintaining ion homeostasis and stimulating antioxidant defence mechanisms. Several halophyte-associated fungi, including members of the genera Fusarium, Chaetomium , and Penicillium , have been reported to exhibit biocontrol potential through the production of antimicrobial metabolites that suppress plant pathogens. In soil ecosystems, endophytes improve nutrient cycling and increase soil organic carbon through their interactions with plant roots. Ecologically, halophyte and fungus associations contribute to ecosystem stability and the bioremediation of polluted soils by facilitating the removal of salts, heavy metals, and organic contaminants. In the food and pharmaceutical sectors, halophyte-associated endophytes represent rich sources of bioactive secondary metabolites and industrially important enzymes. Their application as biofertilizers or bioremediation agents has the potential to expand arable land, enhance food security, and support the development of novel nutraceutical products. This review synthesizes recent physiological, biochemical and field-based evidence on halophyte-associated endophytic fungi, highlighting their diversity, agricultural benefits, ecological functions, and biotechnological applications, with particular emphasis on their role in sustainable development. However, challenges related to field validation, host–endophyte interactions, scalability, and biosafety assessment remain important bottlenecks to their wider application.