| Phytoremediation is a relatively safe, economic and easily operated technique for extracting heavy metals from polluted soils. However, phytoremediators, the plants used for remediation, generally grow slowly, having small biomass and difficulty to absorb and enrich HMs fixed in soils. Using chemical matters such as chelating agents and surfactants to enhance phytoremediation is comparatively available but usually expensive and unfriendly to environment. Therefore, it is very important to search for a microbe-strengthened phytoremediation approach to enhance plant remediation economic ally.Lead and cadmium-resistant strains J34, J113, J115, J116 and J156 were screened out from 46 soil samples. Strain J34 was primarily identified as Erwinia sp., J113 and J116 were identified as Azomona spp. and J115 and J156 were belonged to Pseudomonas. The results of the influence of the temperature, pH, osmolality, oxygen, heavy metals, antibiotics and PAHs on the growth of the strains showed that strains J34, J113, J115, J116 and J156 were all aerobes and could grow at temperature 12℃ to 37 ℃ and pH 5.5 to 9.0. The optimum growth temperature and pH for all strains were 28℃ and 7.2. Strain J116, J113 and J156 grew well in the medium containing NaCl 5%. Strain J34 and J116 could resist various HMs and antibiotics, except Chromium. Strain J113 could grow in the medium added Ni (10 mg。L-1), Zn (400 mg.L-1), Amp (400 mg.L-1), Rif (20 mg.L-1) and J156 could grow in the medium added Cu (20 mg.L-1), Zn (200 mg.L-1), Amp( 400 rng.L-1) , Rif (20 mg.L-1). Strain J115 couldn't resist many HMs and antibiotics, except zinc and ampicillin. All strains were able to tolerate phenanthrene and pyrene.Pb(NO3)2, CdSO4, PbCO3 and CdCO3 were respectively added into the liquid YN medium for investigating the effects of HM-resistant strains on activation of hardly-soluble Pb and Cd in solutions. The results showed that strain J34, J113, J115, J116 and J156 could...
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