From consolidation to innovation: the contribution of molecular markers in the characterization and conservation of garlic (Allium sativum L.)

Abstract Garlic ( Allium sativum L.) stands out among the most relevant vegetable crops worldwide, not only for its nutritional and culinary uses but also for its economic impact and cultural significance in various producing regions. Although it is clonally propagated and presents limitations in sexual recombination (features that contribute to its genomic complexity), molecular investigations have demonstrated that its genetic variability is broader than previously assumed. Early-generation markers, such as random amplified polymorphic DNA (RAPD), amplified frahment length polymorphisms (AFLP), inter simple sequence repeat (ISSR), sequence-related amplified polymorphism (SRAP,) and simple sequence repeat (SSR), played a crucial role in revealing this diversity, thereby supporting cultivar identification and germplasm management. The combination of different marker systems increased the robustness of analyses, enabling the distinction of closely related genotypes and the selection of representative core collections. More recently, high-resolution platforms such as single nucleotide polymorphisms (SNPs), DarTseq, SLAF-seq, and genome-wide association studies (GWAS) have expanded the potential to link genetic variation to complex phenotypes, offering valuable tools for breeding programs and the valorization of local landraces. These advances not only strengthen the conservation of agrobiodiversity but also enhance the inclusion of farming communities in innovation processes. In this review, we synthesize the main advances achieved with different classes of markers, highlighting their contributions to the genetic characterization of garlic and their social and scientific applications. Looking forward, the incorporation of omics and multi-omics approaches tends to deepen our understanding of functional mechanisms and broaden the horizons for the sustainable use of this species on a global scale. Graphical abstract