Germplasm resource and genetic breeding of ornamental Madagascar periwinkle (Catharanthus roseus): a brief review

Madagascar periwinkle ( Catharanthus roseus [L.] G. Don) is a valuable medicinal and ornamental plant, prized for its diverse alkaloid compounds and aesthetic traits. While extensively studied for pharmaceutical applications, its current understanding of preliminary genetic inheritance of ornamental traits and ornamental breeding research are less advanced compared to other horticultural crops. This review systematically examines the germplasm resources, genetic diversity, and breeding advancements in ornamental periwinkle, covering the utilization of wild and cultivated varieties, mutation and polyploidy breeding, and recent genomic sequencing efforts. The potentially genetic mechanisms underlying key ornamental characteristics such as flower color, flower type, and plant architecture are discussed, and emerging approaches evaluated, including marker-assisted selection, interspecific hybridization, and CRISPR-based editing integrated with multi-omics platforms, for trait decoding and precision breeding. Strategies are also highlighted to enhance resistance to prevalent diseases such as die-back and root rot. Finally, future research directions aimed at developing resilient, high-alkaloid cultivars suitable for sustainable ornamental horticulture are proposed. This work provides a comprehensive resource for accelerating molecular breeding and improving ornamental traits in C. roseus .