Unraveling the nano-biochar mediated regulation of heavy metal stress tolerance for sustaining plant health

•Heavy metal stress significantly reduced the crop productivity and cause severe toxicity in plants.•An extended use of soil supplement called nano-biochar increases soil fertility and stress tolerance in plants.•Nano-biochar increases agricultural yields and promotes healthier plant growth.•The use of nano-biochar in sustainable agriculture can lessen the need for chemical fertilizers. Heavy metal (HM) toxicity of agricultural soils poses a major risk to plant health, human life, and global food chain. Crop output and health are negatively impacted when HM levels in agricultural soils reach hazardous points. The nano-biochar (nano-BC) mediated stress tolerance has attracted growing scientific interest because biochar has the potential to be a novel and sustainable solution that may be actively included into the development of sustainable agriculture and food production. At present, biochar is extensively employed as a powerful tool to enhance sustainable agriculture with minimal impact on ecosystems and the environment. Nano-BC offers improved surface area, adsorption and mobility properties in soil compared to traditional fertilizers. Furthermore, nano-BC may prove to be the most practical substitute for traditional waste management techniques because of its affordability, sustainability, and environmental friendliness. In this review, we examine the application of nano-BC in the regulation of HM stress tolerance for improving plant growth and development. We focus on the impact of HMs impact on crop productivity, nano-BC amendments, their application, and production. The article also explores the nano-BC risk and toxicity. Through the perspective of multidisciplinary research, this work highlights the significance of nano-BC as cutting-edge tools in the field of agriculture, igniting a paradigm shift toward sustainable and stress-resilient farming systems.