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The research purpose was the characterization of indigenous heavy metal-resistant plant 19 growth-promoting bacteria (PGPB) from the farmlands located on the Le'an River basin contaminated 20 2 by acid mine drainage and their effects on plant growth, nutrient uptake, antioxidant enzyme activities 21 and metal accumulation. The plant growth-promoting (PGP) traits, including 22 1-aminocyclopropane-1-carboxylic acid deaminase, indoleacetic acid, siderophore, ammonia 23 production and phosphate solubilization, as well as antibiotics, acid/alkali and salt resistance were 24 determined. Ten isolates with relatively high PGP activities were identified to belong to the genera 25 Burkholderia, Paraburkholderia, Cupriavidus, Pseudomonas and Ralstonia. The numerical 26 classification based on bacterial resistant characteristics was mostly consistent with their phylogenetic 27 positions. Burkholderia sp. strain S6-1 and Pseudomonas sp. strain S2-3 possessed both greater PGP 28 activities and resistant characteristics in overall comparison. Compared with non-inoculated plants, 29 strains S6-1 and S2-3 significantly increased the height, dry weight and N uptake of sorghum 30 (Sorghum bicolor L.). The presence of S6-1 significantly increased Pb accumulation and enhanced the 31 translocation of Zn from root to shoot in sorghum. Strain S2-3 helped sorghum to uptake Cu and Zn 32 and improved the remediation effect of sorghum on Cu and Zn. Overall, indigenous PGPB did not 33 show better advantages in improving plant growth than non-indigenous P. putida UW4. Nevertheless, 34indigenous PGPB can be used as better candidates in heavy metal phytoremediation to minimize the 35 potential risks of introducing invasive microbial species into an agricultural ecosystem. 36

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