Nanotechnology opens a large scope of novel applications in the fields of plant nutrition needed to meet the future demands of the growing population because nanoparticles (NPs) have unique physicochemical properties, i.e. high surface area, high reactivity, tunable pore size, and particle morphology. Management of optimum nutrients for sustainable crop production is a priority-based area of research in agriculture. In this regard, nanonutrition has proved to be the most interesting area of research and concerns with the provision of nano-sized nutrients for sustainable crop production. Using this technology, we can increase the efficiency of micro- as well as macronutrients of plants. In the literature, various NPs and nanomaterials (NMs) have been successfully used for better nutrition of crop plants compared to the conventional fertilizers. This review summarizes these NPs and NMs into macro-, micro-, and nanocarrier-based fertilizers and plant-growth-enhancing NPs with unclear mechanisms, describing their role in improving growth and yield of crops, concentration/rate of application, particle size, mechanism of action if known, toxic effects if any, and research gaps in the present research. Moreover, future research directions for achieving sustainable agriculture are also discussed in the appropriate section and at the end in the concluding remarks section.

The pollution of soil and aquatic systems by inorganic and organic chemicals has become a global concern. Economical, eco-friendly, and sustainable solutions are direly required to alleviate the deleterious effects of these chemicals to ensure human well-being and environmental sustainability. In recent decades, biochar has emerged as an efficient material encompassing huge potential to decontaminate a wide range of pollutants from soil and aquatic systems. However, the application of raw biochars for pollutant remediation is confronting a major challenge of not getting the desired decontamination results due to its specific properties. Thus, multiple functionalizing/modification techniques have been introduced to alter the physicochemical and molecular attributes of biochars to increase their efficacy in environmental remediation. This review provides a comprehensive overview of the latest advancements in developing multiple functionalized/modified biochars via biological and other physiochemical techniques. Related mechanisms and further applications of multiple modified biochar in soil and water systems remediation have been discussed and summarized. Furthermore, existing research gaps and challenges are discussed, as well as further study needs are suggested. This work epitomizes the scientific prospects for a complete understanding of employing modified biochar as an efficient candidate for the decontamination of polluted soil and water systems for regenerative development.