Enhanced phytoremediation of crude oil-contaminated soils through zeolite and <i>Pseudomonas aeruginosa</i> RS6 with <i>Parthenium hysterophorus</i>

Total petroleum hydrocarbons (TPHs) are major components of crude oil and pose long-term environmental risks due to their persistence and toxicity in soil, water, and air. Although phytoremediation and bioaugmentation are promising remediation strategies, limited published studies have explored the combined effects of integrating plant, microbial, and mineral systems to enhance hydrocarbon degradation. This study for the first time investigates the combined application of Parthenium hysterophorus, hydrocarbon-degrading Pseudomonas aeruginosa RS6, and zeolite for the remediation of TPH-contaminated soil. Key physiological responses of the plants including chlorophyll content, shoot/root length, and biomass as well as soil properties (pH, moisture, EC, macronutrients) were determined. The combined treatment achieved the highest TPH reduction (85.52%) followed by P. hysterophorus + P. aeruginosa RS6 (80.37%), zeolite alone (29.61%), P. hysterophorus alone (20.39%), and the control (16.6%). These findings suggest that integrating mineral and microbial amendments enhances the phytoremediation efficiency of P. hysterophorus, likely by improving plant tolerance and soil conditions. This novel treatment combination offers a cost-effective, scalable strategy for remediating petroleum-contaminated soil.