Vol.:(0123456789) Environmental Science and Pollution Research https://doi.org/10.1007/s11356-024-35604-9 RESEARCH ARTICLE Exploration and impact of Metlaoui‑Gafsa phosphate rock amendment: the role of Serratia plymuthica BMA1 in phosphate solubilization, heavy metal rhizoaccumulation, and enhanced nutrition in Vicia faba L. Afef Sai 1,2  · Sonia Ben Younes 1,3  · Ali Ellafi 1,4  · Amel Moula 1,2  · Juan Manuel Sánchez‑Yañez 5  · Mohamed Ali Borgi 1,2 Received: 1 July 2024 / Accepted: 16 November 2024 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024 Abstract The geochemical analysis of Gafsa rock phosphate (GRP) revealed relatively high concentrations of essential plant minerals and trace heavy metals (HMs). Environmental contamination factors indicated moderate to very strong HM contamination due to GRP soil amendment. The potential use of the Serratia plymuthica BMA1 strain, which is known for its ability to solubilize GRP, to enhance mineral nutrition in Vicia faba L. and its role in HM rhizoaccumulation from GRP were explored. Pot experiments revealed that bacterization with S. plymuthica BMA1 in V. faba grown in sand supplemented with GRP as the sole source of phosphorus significantly increased the potassium concentration by 64% in roots and 40% in shoots, iron by 20% in roots and 10% in shoots, and manganese by 27% in roots and 20% in shoots compared to that in V. faba not inocu- lated with S. plymuthica BMA1. The total dry biomass of V. faba increased by approximately 85%, while the accumulation of cadmium (Cd), copper (Cu), zinc (Zn), and lead (Pb) in the roots increased by 114%, 30%, 37%, and 44%, respectively. However, in the shoots, they increased by 35%, 10%, 85%, and 25%, respectively, for Cd, Cu, Zn, and Pb compared to those in the non-inoculated V. faba. The evaluation of the HM translocation factor, bioaccumulation factor, and bioconcentration factor with GRP highlighted the key role of S. plymuthica BMA1 in preventing the mobility of toxic HMs from reaching the aerial parts of plants. These findings suggest that S. plymuthica BMA1 has the potential to enhance mineral nutrition in V. faba and facilitate the rhizoaccumulation of toxic HMs, which has implications for plant cultivation and human consumption. Keywords Phosphate rock · Mineral nutrition · Vicia faba L. · Serratia plymuthica BMA1 · Heavy metal rhizoaccumulation · Pollution factors Responsible Editor: Elena Maestri * Sonia Ben Younes benyounes_sonia@yahoo.fr; benyounessonia@gmail.com 1 Faculty of Sciences of Gafsa, University Campus of Ahmed Zarroug, University of Gafsa, 2112 Gafsa, Tunisia 2 Laboratory of Biotechnology and Biomonitoring of the Environment and Oasis Ecosystems (LBBEOE), Faculty of Sciences of Gafsa, University Campus of Ahmed Zarroug, University of Gafsa, 2112 Gafsa, Tunisia 3 Laboratory of Population Health, Faculty of Medicine of Tunis, Environmental Aggressors and Alternative Therapies (LR24ES10), Tunis, Tunisia 4 Laboratory of Analysis, Faculty of Pharmacy of Monastir, Treatment and Validation of Environmental Pollutants and Products, Monastir, Tunisia 5 Environmental Microbiology Laboratory, Research Institute in Chemistry and Biology, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, México