The effect of endophytic halotolerant bacteria inoculation in the development of soybean seedling under salinity stress

Abstract

Salinity stress affects more than 20% of the world's agricultural area, which causes a decrease in productivity by increasing osmotic pressure, reducing water absorption, diminishing nodulation, and inhibiting soybean seed germination and seedling growth. Using symbiotic microbes is an effective biotechnique for improving salinity resilience in agriculture, especially for seedling development. This study aims to investigate the impact of halotolerant bacteria on plant growth and biochemical parameters of soybeans in saline environment. The experiment involved Devon 1 soybean variety and four endophytic halotolerant bacteria namely B0 (control), B3 (ACC-deaminase production bacteria), B4 (N2-fixing bacteria), and B5 (IAA production bacteria + Phosphate Solubilizing (PS) bacteria + ACC-deaminase production bacteria + N2-fixing bacteria). Hoagland solution was used as the germination medium, and NaCl was added at doses of 0, 40, 80, 120, and 160 mM to create the salinity stress treatment. The results showed that halotolerant bacteria treatment of B3, B4, and B5 enhances the tolerance of Devon 1 soybean seeds to salinity stress and potential as PGP which is found to stimulate plant development and promote the growth of Devon 1 even under high salinity conditions of up to 80 mM.