Bioremediation of cadmium-phoxim co-contamination by an autochthonous pollutant-resistant consortium enhances Ligusticum Chuanxiong Hort. resistance.

Prominent cadmium (Cd) pollution and widespread phoxim (pH) use hinder the growth and medicinal value of Ligusticum chuanxiong Hort. (Chuanxiong). While bioremediation by rhizobacteria helps plants counter pollutants, the specific roles of indigenous resistant consortia collected from polluted soils in immobilizing heavy metals, degrading pesticides, and enhancing plant stress tolerance remain insufficiently explored. Here, an indigenous pollutant-resistant consortium (RM) was developed from a highly Cd-polluted area (14.85 mg/kg Cd) as a bioremediation strategy to alleviate stress on Chuanxiong. The RM was specifically enriched with a Cd-pH co-resistant strain, Halomonas spp. TS2. Through 16S rRNA sequencing, active microorganisms within RM was identified, including Bacillus, Acinetobacter, Enterococcus, Paraclostridium, and Staphylococcus. Pot experiments demonstrated that RM increased Chuanxiong biomass by 93.38 % under Cd-contaminated and by 32.89 % under Cd-pH co-contaminated. Furthermore, RM enhanced pH degradation, stabilized soil compounds, and reduced Cd bioavailability, thereby mitigating oxidative damage and altering the diversity and composition of Cd-pH-resistant organisms. These results indicate that utilizing indigenous microbial consortia as a bioremediation strategy can effectively improve soil health and enhance the sustainable cultivation of medicinal herbs in environments heavily contaminated.