Breeding for nutrient use efficiency in crop plants: Mechanistic insights, genetic determinants, and emerging breeding technologies

Sustainable agricultural production requires significant improvements in the efficiency with which crops utilize mineral nutrients. Nitrogen (N), phosphorus (P), and potassium (K) are indispensable for plant growth; however, inefficient fertilizer recovery results in economic losses and serious environmental consequences. Genetic enhancement of nutrient use efficiency (NUE) represents a durable and environmentally responsible strategy to reduce fertilizer dependence while sustaining yield. This review synthesizes current knowledge on the physiological processes governing nutrient acquisition and utilization, the quantitative genetic architecture underlying NUE, and advances in molecular breeding, genomic prediction, and gene editing. Emphasis is placed on major cereals including Oryza sativa, Triticum aestivum, and Zea mays. Key constraints such as genotype × environment interactions, trade-offs between yield and grain protein, and phenotyping bottlenecks are critically evaluated. Integration of multi-omics platforms, high-throughput phenomics, and predictive breeding frameworks is proposed as a pathway toward next-generation nutrient-efficient cultivars.