Neighbor Presence of Plant Growth-promoting Rhizobacteria (PGPR) and Arbuscular Mycorrhizal Fungi (AMF) Can Increase Sorghum Phytoremediation Efficiency in a Soil Treated with Pb Polluted Cow Manure

Background: The present study aimed to evaluate the effects of PGPR and AMF on the changes in sorghum phytoremediation efficiency in the soil amended with lead (Pb)- polluted cow manure. Methods: Treatments consisted of applying two rates of Pb [0 (Pb0) and 800 (Pb800) mg/kg] polluted cow manure [0 (C0) and 30 (C30) t/ha], two levels of AMF [without (AMF-) and with (AMF+)] and PGPR (without (PGPR-) and with (PGPR+) inoculation. Pseudomonas sp. R9 was considered as a PGPR bacteria. The plant used in this experiment was sorghum. Plant Pb concentration was measured using atomic absorption spectroscopy. Results: The highest plant Pb concentration belonged to the cultivated plant in the soil treated with 30 t/ha Pb-polluted cow manure, while the lowest that was observed in the soil without amending cow manure in the absence of PGPR or AMF. The presence of AMF significantly increased the Pb translocation value and sorghum phytoremediation efficiency by 8% and 13.4%, respectively. Conclusion: According to the results, the inoculated plant with PGPR and AMF had positive effects on increasing Pb phytoremediation efficiency that, which is notable in environmental studies. However, the effects of soil chemical properties on Pb phytoremediation efficiency cannot be overlooked.