Impact of Soil Inoculation with Bacillus amyloliquefaciens FZB42 on the Phytoaccumulation of Germanium, Rare Earth Elements, and Potentially Toxic Elements

Abstract

Bioaugmentation promises benefits for agricultural production as well as for remediation and phytomining approaches. Thus, this study investigated the effect of soil inoculation with the commercially available product RhizoVital®42, which contains Bacillus amyloliquefaciens FZB42, on nutrient uptake and plant biomass production as well as on the phytoaccumulation of potentially toxic elements, germanium, and rare earth elements (REEs). Zea mays and Fagopyrum esculentum were selected as model plants, and after harvest, the element uptake was compared between plants grown on inoculated versus reference soil. The results indicate an enrichment of B. amyloliquefaciens in inoculated soils as well as no significant impact on the inherent bacterial community composition. For F. esculentum, inoculation increased the accumulation of most nutrients and As, Cu, Pb, Co, and REEs (significant for Ca, Cu, and Co with 40%, 2042%, and 383%, respectively), while it slightly decreased the uptake of Ge, Cr, and Fe. For Z. mays, soil inoculation decreased the accumulation of Cr, Pb, Co, Ge, and REEs (significant for Co with 57%) but showed an insignificant increased uptake of Cu, As, and nutrient elements. Summarily, the results suggest that bioaugmentation with B. amyloliquefaciens is safe and has the potential to enhance/reduce the phytoaccumulation of some elements and the effects of inoculation are plant specific.

J. curcas and Manihot esculenta are potential super plants for phytoremediation in multi-contaminated mine spoils

“…All these remediation techniques have certain merits and drawbacks, as they leave secondary residual effects in soils. Nonetheless, phytoremediation (use of accumulator plants in soil cleaning) presents the least harmful effects, cost-effective amongst other techniques and suits the increasing quest for environmental sustainability [4,[18][19][20][21]. Phytoremediation may be grouped based on their operating mode and they include; phytoextraction, phytostabilisations, phytofiltration, phytodegradation, phytovolatilisation, and rhizodegradedation [22].…”

Phytoremediation of Pollutants: Applicability and Future Perspective

“…Due to its strong potential in this field, this technique must be deepened and tested. The effect of the application of the commercial product RhizoVital ® 42, containing Bacillus amyloliquefaciens FZB42, on soil polluted by potentially toxic elements (PTEs), critical raw materials (CRMs, such as germanium -Ge), and rare earth elements (REEs) was the object of the study by Okoroafor et al [6]. Results showed that B. amyloliquefaciens successfully integrated (relative abundance 1%) into the bacterial community, which was not altered by the enrichment.…”