Nanopesticides-rhizo-microbiome interactions: Biochemical mechanisms, ecotoxicological effects and implications for pesticide fate and transformation.

Nano-enabled pesticides (NanoPs) formulations have emerged as promising alternative to conventional pesticides by improving ingredient stability, delivery, and controlled release. However, their unique physicochemical properties also influence interactions with soil microorganisms, raising concerns regarding ecological safety and long-term impacts on soil ecosystem functions. This review has critically synthesized the current knowledge about NanoPs-microbiome interactions with a focus on biochemical mechanisms underlying microbial responses and implications for pesticide fate and transformation. We review how the properties of NPs (e.g., particle size, surface charge, coatings, dissolution, and eco-corona formation) influence mobility, bioavailability, and microbial exposure. Mechanistic evidence of oxidative stress, membrane damage, enzyme inhibition, metal-ion-mediated toxicity and quorum sensing interference is critically synthesized to elucidate biochemical basis of NanoPs-induced microbial responses. Recent advances in high throughput sequencing and multi-omics technologies are also used to assess changes in microbial diversity, community composition, functional redundancy, microbial interaction networks and ecosystem resilience. The review further compares conventional and nano-formulated pesticides, highlighting differences in microbial toxicity, degradation kinetics, transformation pathways, and metabolite profiles. Current challenges associated with environmental fate assessment, standardized ecotoxicological testing, and microbiome-informed risk evaluation are critically discussed. Emerging opportunities for integrating metagenomics, artificial intelligence, and predictive modelling into environmental risk assessment are also highlighted. Finally, we propose a future research framework centered on microbiome-informed safe-by-design NanoPs, standardized testing protocols, and long-term field validation to support development of environmentally responsible nano-enabled crop protection technologies while preserving soil biodiversity and ecosystem functions.