Progress in phylogenetics, multi-omics and flower coloration studies in Rhododendron

The genus Rhododendron exhibits an immense diversity of flower colors and represents one of the largest groups of woody plants, which is of great importance for ornamental plant research. This review summarizes recent progress in deciphering the genetic basis for flower coloration in Rhododendron. We describe advances in phylogenetic reconstruction and genome sequencing of Rhododendron species. The metabolic pathways of flower color are outlined, focusing on key structural and regulatory genes involved in pigment synthesis. Gene duplications and losses associated with color diversification are discussed. In addition, the application of multi-omics approaches and analysis of gene co-expression networks to elucidate complex gene regulatory mechanisms is emphasized. This synthesis of current knowledge provides a foundation for future research on the evolution of flower color diversity within the Rhododendron lineage. Ultimately, these discoveries will support breeding endeavors aimed at harnessing the genetics of flower coloration and developing novel cultivars that exhibit desired floral traits.