The Role of Halotolerant PGPMs in Enhancing Salt Stress Tolerance in Hydroponically Grown Crops

In the context of global climate change, salinity has emerged as a significant abiotic stressor affecting crop productivity, particularly in regions reliant on hydroponic systems for agricultural production. This study investigates the role of halotolerant plant growth-promoting microorganisms (PGPMs) in enhancing salt stress tolerance in hydroponically grown crops. Halotolerant PGPMs possess unique adaptations that enable them to thrive in saline environments, thus offering a potential biotechnological solution to mitigate the adverse effects of salinity on plant growth and development. This research encompasses a comprehensive review of the mechanisms through which halotolerant PGPMs promote plant growth under saline conditions. Key mechanisms include the production of osmoregulatory compounds, such as exopolysaccharides and compatible solutes, which help stabilize cellular functions in high-salinity environments. Additionally, these microorganisms enhance nutrient availability and uptake by solubilizing essential minerals, thereby improving plant nutritional status under stress. Field experiments were conducted to evaluate the efficacy of selected halotolerant PGPM strains on the growth performance, physiological responses, and biochemical attributes of hydroponically grown crops, specifically focusing on species such as lettuce (Lactuca sativa) and spinach (Spinacia oleracea). The results indicate that the application of halotolerant PGPMs significantly improved plant biomass, root development, and chlorophyll content, while also enhancing antioxidant enzyme activity and reducing oxidative stress markers in plants subjected to salt stress. Furthermore, the study emphasizes the synergistic interactions between halotolerant PGPMs and plant root systems, highlighting the importance of microbial communities in establishing a resilient hydroponic ecosystem. The findings suggest that integrating halotolerant PGPMs into hydroponic systems can serve as a sustainable strategy for improving crop resilience to salinity, ultimately contributing to food security in saline-prone regions. This research contributes to the growing body of knowledge on microbial biotechnology in agriculture, providing insights into the potential of halotolerant PGPMs as biofertilizers in hydroponic systems. Future directions include exploring the molecular mechanisms underlying plant-microbe interactions in saline conditions and assessing the long-term impacts of halotolerant PGPM application on crop productivity and soil health. By enhancing our understanding of these interactions, this study lays the groundwork for developing innovative agricultural practices that can effectively address the challenges posed by salt stress in hydroponically grown crops.