Nanofertilizers: Applications, Challenges, and Their Role in Sustainable Agriculture

Abstract

Nano-fertilizers are a new technology that has attracted more attention in plant nutrition since they can be designed to improve the efficiency of nutrient delivery, control nutrient release and reduce different types of nutrient loss in soil and surrounding environment. Such fertilizers include materials containing nutrients in nano-form, nano-carriers that can transport and release nutrients in a controlled manner or hybrid formulations containing mineral, organic and biological components. This review covers the concept of nano-fertilizers, their classifications, preparation methods and mechanisms of action. Discussion is also on their potential impact on plant growth, crop productivity and nutrient-use efficiency. The relation of these technologies to sustainable agriculture is also discussed, including possible risks such as phytotoxicity, environmental accumulation, effects on micro-organisms and economic viability. The current literature indicates some nano-formulations may improve the availability or utilization efficiency of selected nutrients under specific conditions. However, the response is dependent on type of material, dosage, crop, soil and mode of application. One of the major challenges that hinder the generalization of findings is the lack of long-term field trials and the absence of standardized protocols for characterization and evaluation. The review concludes that nano-fertilizers are a promising technology which can contribute to the advancement of plant nutrition systems if rigorously evaluated based on scientific evidence, economic feasibility and environmental safety and integrated into comprehensive nutrient management strategies rather than being seen as a universal substitute for conventional fertilizers.