Microbial Regulation of Toxic Metal(loid) Cycling in Soils and Crops

Soil microbiology and geomicrobiology are central to understanding how toxic metal(loid)s move through soil–plant systems. Microorganisms regulate contaminant immobilisation, mobilisation, oxidation–reduction, methylation, demethylation and volatilisation, thereby influencing metal(loid) speciation, bioavailability, persistence and transfer to crops. However, the extent to which microbial communities, functional genes, metabolites and mineral–microbe associations control these processes remains difficult to predict across contrasting soil conditions. Recent studies have shown that microbial transformations and rhizosphere interactions can substantially alter metal(loid) mobility and plant uptake, while advances in omics, isotope tracing, spectroscopy and nanoscale imaging are improving the resolution of mechanistic investigations. Nevertheless, important gaps remain in linking molecular and microscale processes with field-scale behaviour, crop safety and long-term remediation outcomes. A better integrated understanding is needed to resolve how microbial functions operate within complex mineral, organic matter and plant-associated environments, and how these functions can be safely and reliably harnessed.This Research Topic aims to clarify the mechanisms through which microorganisms and their associated minerals regulate toxic metal(loid) cycling in soils and their transfer to crops. It will examine how microbial community composition, functional genes, metabolic products and microbial–mineral interactions influence metal(loid) speciation, transformation, bioavailability and plant uptake. The Research Topic also seeks to evaluate the effectiveness of microbial consortia, inoculants and other biologically based interventions for reducing toxic metal(loid) accumulation in crops, with particular attention to mechanistic evidence, field relevance, persistence, scalability, ecological safety and unintended effects.To gather further insights in the microbiological chemistry and geomicrobiology of toxic metal(loid) transformation in soil–plant systems, this Research Topic will focus on terrestrial environments and crop production while welcoming laboratory, greenhouse, mesocosm and field-based research. Relevant themes include, but are not limited to:• Microbial oxidation–reduction of toxic metal(loid)s• Microbial methylation, demethylation and volatilisation• Mineral–microbe interactions controlling metal(loid) sequestration and release• Rhizosphere biogeochemistry and plant–microbe interactions• Microbial regulation of metal(loid) speciation, bioavailability and plant uptake• Functional genes, metabolites and metabolic pathways involved in transformation processes• Metagenomic, transcriptomic, proteomic and metabolomic approaches• Microbial consortia, bioinoculants and engineered or enriched microbial communities• Biologically based strategies for reducing toxic metal(loid) accumulation in crops• Persistence, scalability and ecological safety of microbial interventions• Field validation, risk assessment and long-term performance of remediation approaches Topic editors: Sudhakar Srivastava, Mohammad Mahmudur Rahman, Jyoti Mathur, Penradee Chanpiwat Source: https://www.frontiersin.org/research-topics/86770/microbial-regulation-of-toxic-metalloid-cycling-in-soils-and-crops