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

Overview

This review synthesizes advances in molecular marker applications for garlic (Allium sativum L.) genetic characterization and conservation. Garlic exhibits complex genomics due to clonal propagation and limited sexual recombination, yet molecular investigations have revealed genetic variability extending beyond earlier assessments. The review examines the progression from early-generation marker systems to contemporary high-resolution platforms and their contributions to cultivar identification, germplasm management, and breeding applications.

Methods and approach

The review consolidates findings from multiple molecular marker systems employed in garlic research, spanning early-generation markers (RAPD, AFLP, ISSR, SRAP, SSR) through contemporary approaches (SNP panels, DarTseq, SLAF-seq, GWAS). The synthesis evaluates how marker systems function individually and in combination to distinguish closely related genotypes, enable core collection selection, and establish genotype-phenotype associations. The framework positions these technologies within broader conservation and breeding contexts.

Results

Early-generation markers demonstrated capacity to reveal genetic diversity within garlic germplasm, supporting cultivar identification and population structure analysis. Combining multiple marker systems enhanced analytical robustness and enabled discrimination of closely related genotypes. High-resolution platforms including SNP genotyping, DarTseq, SLAF-seq, and GWAS expanded capability for linking genetic variation to complex phenotypes. These advances facilitated characterization of local landraces and supported the delineation of representative core collections. Integration of molecular data with agronomic and phenotypic information strengthened both fundamental understanding and applied breeding outcomes.

Implications

Molecular markers have transitioned from confirmatory tools to central instruments in garlic germplasm characterization and conservation strategy. The capacity to distinguish genetic variation at multiple resolutions enables more informed cultivar selection, germplasm banking, and trait-based breeding design. Implementation of high-resolution marker systems supports valorization of local landraces and enhances their integration into formal breeding programs, with potential for crop improvement aligned with regional agricultural systems. Consolidation of molecular marker approaches with conservation practices strengthens agrobiodiversity protection while creating frameworks for farming community participation in innovation processes. The transition toward omics and multi-omics methodologies offers potential for deeper characterization of functional genetic mechanisms and improved understanding of phenotypic variation. These technical advances support more sustainable and contextually appropriate approaches to garlic production and germplasm stewardship on global scales.