SNP discovery and applications in plant genetics for sustainable food security: A review

Single nucleotide polymorphisms represent the most abundant form of genetic variation in plant genomes and have become fundamental markers in modern plant genetics and breeding. Increasing global demand for food, combined with the pressures of climate change, environmental stress, and declining arable land, requires accelerated crop improvement strategies that exceed the capacity of conventional breeding approaches. In this context, SNP-based genomic technologies provide high-resolution tools for analyzing genetic diversity, identifying trait-associated loci, and enhancing selection efficiency in breeding programs. This review provides a comprehensive synthesis of SNP discovery methodologies, tracing their development from early Sanger sequencing approaches to advanced next-generation sequencing technologies, including whole-genome resequencing, genotyping-by-sequencing, and high-density SNP arrays. The article further examines the diverse applications of SNP markers in plant genetics, including genetic diversity analysis, linkage mapping, genome-wide association studies, marker-assisted selection, genomic selection, and evolutionary research. Key analytical and technical challenges, particularly those related to polyploid genome complexity, large-scale genomic data processing, and accurate variant interpretation, are critically discussed. In addition, emerging developments such as graph-based pangenomes, long-read sequencing technologies, machine learning-assisted SNP prioritization, and multi-omics integration are highlighted as promising directions for future research. By integrating recent technological advances with established genomic approaches, this review emphasizes the central role of SNP-based genomics in accelerating crop improvement and enabling climate-resilient, sustainable agricultural systems that support global food security.