Metabolomic and Metagenomic Insights Into Halotolerant Microbial Formulations for Reclaiming Effluent‐Stressed Soils and Enhancing Chilli Productivity

ABSTRACT This study evaluated halotolerant microbial formulations for mitigating salinity stress and improving chilli ( Capsicum annuum ) growth in pulp and paper mill‐contaminated soil. Formulations combining Bacillus velezensis , Kocuria rhizophila , and Kosakonia radicincitans were applied as carrier‐based (CBHF, 4 kg ha − 1 ) and liquid‐based (LBHF, 1500 mL ha − 1 ) treatments, selected through statistically significant improvements in yield and soil fertility. Experiments were conducted with sterile carrier and buffer controls. CBHF and LBHF significantly enhanced organic carbon, nitrogen, and microbial diversity. Metabolomic profiling of root exudates revealed increased osmoprotectants, sugars, and GABA, indicating improved rhizosphere resilience. Metagenomic analysis showed enrichment of salt‐tolerant and plant growth–promoting taxa ( Actinobacteria , Firmicutes ) and functional genes linked to osmoregulation and phosphate solubilization. Field ECE fluctuations were attributed to continuous effluent irrigation. Overall, halotolerant microbial formulations improved soil–plant–microbe interactions and nutrient cycling, demonstrating sustainable potential for bioremediating saline effluent‐irrigated soils.