Next-generation strategies for nitrogen-efficient maize production for a greener tomorrow

Abstract

Background: Enhancing nitrogen use efficiency (NUE) in maize is central to addressing the dual challenges of increasing crop productivity and minimizing environmental nitrogen (N) losses. Nitrogen is essential for plant growth, but inefficient use leads to significant environmental impacts. Traditional fertilization methods often result in excessive N loss, which contributes to pollution and reduces sustainability. Improving NUE is, therefore, a key priority for both agricultural productivity and environmental protection. Scope: This review integrates multidisciplinary insights into the agronomic, molecular, and technological dimensions of NUE in maize. Agronomic strategies such as the use of biofertilizers, biochar, mulching, intercropping, and green manuring are evaluated for their effectiveness in reducing N losses and promoting plant uptake. The role of root system architecture and soil-plant interactions is discussed as a foundation for understanding NUE at a physiological level. Technological advancements like precision agriculture and remote sensing are reviewed for their potential to optimize N application in real time. On the molecular front, methods including QTL mapping, GWAS, and candidate gene studies are explored for identifying genetic components of NUE. The paper also covers multi-omics approaches combining genomic, transcriptomic, and metabolomic data for deeper insights into N-related pathways. CRISPR-Cas gene-editing is highlighted as a transformative tool for breeding N-efficient maize varieties. Conclusions: By linking agronomic innovations with molecular advancements, the review provides a comprehensive roadmap for enhancing NUE in maize. It emphasizes the synergy between traditional farming practices and cutting-edge genetic and digital technologies. Ultimately, the integration of these approaches offers a sustainable path toward improving maize productivity while mitigating environmental impact, especially in the context of climate change and increasing global food demands. Significance: This review consolidates complex, multidisciplinary advances into a clear framework for improving NUE in maize, supporting sustainable crop production through actionable, innovation-driven strategies.