Induction Effect of Some Species of Glomus and Pseudomonas in Phytoremediation of Soil Pb by Hyoscyamus (Hyoscyamus niger)

Phytoremediation، the use of plants in association with microorganisms for remediation of contaminated sites، is a promising technique for reclamation of heavy metals contaminated soils. In this research the role of selected species of Glomus (G. intraradices، G. mosseae و G. fasciculatum) and Pseudomonas (P. putida، P. fluorescens و P. aeruginosa) in phytoremediation of soil Pb contamination by Hyoscyamus (Hyoscyamus niger) was investigated. This study was carried out in greenhouse condition as a factorial experiment based on a randomized complete block design with two factors including Pb concentration (in four levels) and microbial treatment (in three levels) and in three replications under greenhouse conditions. A soil sample was spiked uniformly with Pb-nitrate salt to create different Pb concentrations (0، 250، 500 and 1000 mg kg-1). The contaminated soils were then sterilized and subsequently inoculated with the species of Glomus fungi and Pseudomonas bacteria. Hyoscyamus plant was grown in these soils. Results indicate that Glomus fungi and Pseudomonas bacteria increased significantly (P≤ 0. 05) the amount of proline، soil bioavailable Pb، biomass of root and shoot and the amount of Pb was stabilized and extracted by Hyoscyamus niger as compared to the control treatment. Glomus fungi and Pseudomonas bacteria increased the amounts of extracted Pb by shoots up to 2. 7 and 2 times and the stabilized Pb in roots up to 3. 1 and 1. 9 times higher than corresponding control treatments، respectively. It can be concluded that the studied microbes are promising agents to alleviate Pb phytotoxicity and to enhance Pb phytoremediation efficiency by Hyoscyamus.