Institute of Environmental Sciences and Engineering (IESE), School of Civil and Environmental Engineering (SCEE), National University of Sciences and Technology (NUST), Islamabad, Pakistan.
Ecolab, Université de Toulouse, CNRS, Toulouse, France.
Environ Sci Pollut Res Int. 2019 Aug;26(23):23788-23797. doi: 10.1007/s11356-019-05656-3. Epub 2019 Jun 17.
Lead (Pb) is known for its low mobility and persistence in soils. The main aim of the present study was to explore potential of different fungal strains to promote phytoextraction of Pb-contaminated soils. Five non-pathogenic fungal strains (Trichoderma harzianum, Penicillium simplicissimum, Aspergillus flavus, Aspergillus niger, and Mucor spp.) were tested for their ability to modify soil properties (pH and organic matter) and to increase Pb phytoavailability at varying concentrations. Lead tolerance of fungal strains followed the decreasing order as A. niger > T. harzianum > A. flavus > Mucor sp. > P. simplicissimum. Lead solubility induced by A. flavus and Mucor spp. was increased by 1.6- and 1.8-fold, respectively, as compared to the control soil (Pb added, without fungi). A. flavus and Mucor spp. lowered the soil pH by - 0.14 and - 0.13 units, in soils spiked with 2000 mg Pb kg. The maximum increase in the percentage of organic matter (OM) recorded was 1.7-fold for A. flavus at 500 mg Pb kg soil. Plant growth-promoting assays confirmed the beneficial role of these fungal strains. Significantly high production of IAA (249 μg mL) and siderophores (61%) was observed with A. niger, and phosphate solubilization with P. simplicissimum (58 μg mL). Based on the results in Pb-contaminated soils, Pelargonium hortorum L. inoculated with Mucor spp. showed the potential to enhance phytoextraction of Pb by promoting Pb phytoavailability in soil and improving plant biomass production through plant growth-promoting activities.
铅（Pb）的特点是在土壤中迁移性和持久性低。本研究的主要目的是探索不同真菌菌株促进受 Pb 污染土壤植物提取的潜力。测试了五种非病原真菌菌株（哈茨木霉、简单青霉、黄曲霉、黑曲霉和毛霉），以评估它们改变土壤特性（pH 和有机质）和增加不同浓度下 Pb 植物可利用性的能力。真菌菌株对 Pb 的耐受性遵循以下降序排列：黑曲霉>哈茨木霉>黄曲霉>毛霉>简单青霉。与对照土壤（添加 Pb 但无真菌）相比，黄曲霉和毛霉诱导的 Pb 溶解度分别增加了 1.6 倍和 1.8 倍。黄曲霉和毛霉使添加了 2000mg Pb kg 的土壤的 pH 值分别降低了 0.14 和 0.13 个单位。在添加 500mg Pb kg 土壤中，毛霉记录的有机物质（OM）最大增加率为 1.7 倍。植物生长促进试验证实了这些真菌菌株的有益作用。黑曲霉产生的 IAA（249μg mL）和铁载体（61%）显著较高，简单青霉可溶解磷酸盐（58μg mL）。根据受 Pb 污染土壤的结果，接种毛霉的天竺葵 Pelargonium hortorum L. 通过促进土壤中 Pb 的植物可利用性和通过植物生长促进活性提高植物生物量生产，显示出增强 Pb 植物提取的潜力。
