Yahaghi Zahra, Shirvani Mehran, Nourbakhsh Farshid, de la Peña Teodoro Coba, Pueyo José J, Talebi Majid
Department of Soil Science, College of Agriculture, Isfahan University of Technology, Isfahan 84156-83111, Iran.
Institute of Agricultural Sciences ICA-CSIC, 28006 Madrid, Spain.
J Microbiol Biotechnol. 2018 Jul 28;28(7):1156-1167. doi: 10.4014/jmb.1712.12038.
The aim of this study was to isolate and characterize lead (Pb)-solubilizing bacteria from heavy metal-contaminated mine soils and to evaluate their inoculation effects on the growth and Pb absorption of . The isolates were also evaluated for their plant growth-promoting characteristics as well as heavy metal and salt tolerance. A total of 171 Pb-tolerant isolates were identified, of which only 15 bacterial strains were able to produce clear haloes in solid medium containing PbO or PbCO, indicating Pb solubilization. All of these 15 strains were also able to dissolve the Pb minerals in a liquid medium, which was accompanied by significant decreases in pH values of the medium. Based on 16S rRNA gene sequence analysis, the Pb-solubilizing strains belonged to genera , and . A majority of the Pb-solubilizing strains were able to produce indole acetic acid and siderophores to different extents. Two of the Pb-solubilizing isolates were able to solubilize inorganic phosphate as well. Some of the strains displayed tolerance to different heavy metals and to salt stress and were able to grow in a wide pH range. Inoculation with two selected Pb-solubilizing and plant growth-promoting strains, ( YSP40 and YSP151) and their consortium enhanced the growth and Pb uptake of plants grown in a metal-contaminated soil. The bacterial strains isolated in this study are promising candidates to develop novel microbe-assisted phytoremediation strategies for metal-contaminated soils.
本研究的目的是从重金属污染的矿山土壤中分离并鉴定能溶解铅（Pb）的细菌，并评估它们对[植物名称]生长和铅吸收的接种效果。还对分离菌株的植物促生长特性以及重金属和盐耐受性进行了评估。共鉴定出171株耐铅菌株，其中只有15株细菌菌株在含有PbO或PbCO的固体培养基中能够产生清晰的晕圈，表明具有铅溶解能力。这15株菌株在液体培养基中也都能够溶解铅矿物，同时培养基的pH值显著降低。基于16S rRNA基因序列分析，这些能溶解铅的菌株属于[具体菌属名称]属。大多数能溶解铅的菌株能够不同程度地产生吲哚乙酸和铁载体。其中两株能溶解铅的分离菌株还能够溶解无机磷酸盐。一些菌株对不同的重金属和盐胁迫具有耐受性，并且能够在较宽的pH范围内生长。接种两种选定的能溶解铅且促进植物生长的菌株（YSP40和YSP151）及其联合体，提高了在金属污染土壤中生长的[植物名称]的生长和铅吸收。本研究中分离出的细菌菌株是开发针对金属污染土壤的新型微生物辅助植物修复策略的有潜力的候选菌株。
