Biochar and microbial inoculants as natural agents with beneficial potential for soil health and plant growth

Abstract

Microbes and biochar play a crucial role in plant and soil health management; their combined applications have emerged as a promising tool in sustainable agriculture and this research area is a major focus of scientists, particularly in the last few years. These inoculants improve soil physicochemical and biological properties, safeguard plant and soil from biotic and abiotic stresses and enhance nutrient cycling. There are several recent papers available on the sole application of biochar and the microbial role in agriculture, but a combined role in sustainable agriculture is limited. The recent studies have exhibited that a combined application of biochar and microbial inoculants increases yields up to 40% in various crops, including wheat, maize, rice, vegetables and legumes under field conditions, alongside reducing chemical dependency by 20 to 50%. Moreover, innovations in the formulation of nano biochar and co-inoculant strategy foster beneficial microbiomes addressing climate-smart farming challenges. However, the long-term field scalability gap persists in the standardization of application rates and region-specific adaptation, especially in tropical soils. Therefore, future research should prioritize mechanistic insights via metabolomics and multi-omics to scale these interventions for global food security and soil health restoration. Therefore, this review focuses on recent progress (particularly 2020-2026) in how biochar-microbes interaction plays pivotal role in enhancing soil structure, pH balance, water retention and carbon sequestration while reducing nutrient leaching and heavy metal toxicity, boosting enzymatic (dehydrogenase, phosphatase, urease, cellulase) activity, nitrogen fixation, decomposition of organic matter and plant resilience against stresses. The potential of integrated biochar-microbial systems for soil revitalization and advocates for interdisciplinary research to bridge scalability gaps, fostering resilient farming systems worldwide.