Molecular markers and genomic resources in caraway (Carum carvi L.): Current status, research gaps, and strategic directions for breeding

Caraway (Carum carvi L.) is an economically important spice and medicinal crop valued for its essential oil composition, particularly its high content of carvone and limonene. Despite its commercial relevance, compared with that of other Apiaceae species, the development of genomic resources remains limited. Molecular research has progressed from early dominant marker systems, including random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR), to more recent SNP-based genotyping approaches that clarify population structure and flowering-type differentiation. However, key genomic resources, such as simple sequence repeat (SSR) markers, a high-quality reference genome, quantitative trait locus (QTL) mapping, genome-wide association studies (GWAS), and transcriptomic datasets, are still lacking. This review synthesises current knowledge on molecular marker applications in caraway and identifies major gaps limiting breeding progress. Evidence from related Apiaceae species indicates that systematic SSR development and integration of genome-based tools can substantially enhance breeding efficiency. Particular emphasis is placed on a phased strategy for SSR development in caraway, positioned as complementary to single-nucleotide polymorphism (SNP)-based approaches within a progressive genome-enabled breeding framework. Strengthening the molecular infrastructure of caraway will support precision breeding aimed at improving yield stability, essential oil quality, and environmental adaptability.