Laboratory of Planetology and Geodynamics of Nantes, UMR 6112 CNRS, Faculty of Sciences and Technology of Nantes, BP 92208, 44322, Nantes Cedex 3, France; Research Unit on Coastal and Urban Environments, University of Sfax, National Engineering School of Sfax, BP 1173, 3038, Sfax, Tunisia; Tunisian Chemical Group, M'Dhilla-Gafsa Factory, B.P. 215, 2100, Gafsa, Tunisia.
Laboratory of Planetology and Geodynamics of Nantes, UMR 6112 CNRS, Faculty of Sciences and Technology of Nantes, BP 92208, 44322, Nantes Cedex 3, France.
J Environ Manage. 2020 Apr 15;260:110063. doi: 10.1016/j.jenvman.2020.110063. Epub 2020 Jan 24.
Bacteria isolated from soils in the vicinity of phosphogypsum (PG) stockpiles were studied for their potential use in bioaugmentation-assisted phytoextraction. Quick, miniaturized biochemical tests were performed in the presence of metal trace elements (MTE), including rare earth elements (Cd, Sr, Ce, La, Nd and Y), corresponding to their bioavailable concentrations in PG. The intention herein was to assess the capacity of bacteria to: i) grow in PG; ii) produce indole acetic acid and ACC deaminase to promote plant growth and reduce stress; and iii) produce siderophores, including pyoverdine, to mobilize MTE. Results showed that even at maximum PG concentration (10 g/L and pH 3.40), 7 out of 32 isolates were able to grow. The biochemical tests showed differences in the presence or absence of MTE. The presence of MTE seems to promote the production of IAA by a factor of 3.25. On the contrary, it inhibits ACC deaminase and siderophore production, including pyoverdine. According to a scoring method applied, the two most efficient isolates exhibiting maximum metabolite production were identified as Bacillus sp.
从磷石膏（PG）堆存场附近土壤中分离出的细菌，因其在生物强化辅助植物提取中的潜在应用而受到研究。在含有金属微量元素（MTE）的情况下，包括稀土元素（Cd、Sr、Ce、La、Nd 和 Y），快速、微型生化测试在相应的 PG 生物可利用浓度下进行。目的是评估细菌的以下能力：i）在 PG 中生长；ii）产生吲哚乙酸和 ACC 脱氨酶以促进植物生长和减轻压力；iii）产生铁载体，包括绿脓菌素，以动员 MTE。结果表明，即使在 PG 浓度最高（10 g/L 和 pH 3.40）的情况下，32 个分离物中有 7 个能够生长。生化测试显示 MTE 的存在与否存在差异。MTE 的存在似乎将 IAA 的产生促进了 3.25 倍。相反，它抑制了 ACC 脱氨酶和铁载体的产生，包括绿脓菌素。根据应用的评分方法，确定了两种最有效的分离物，它们具有最大的代谢产物产生，被鉴定为芽孢杆菌。
