Multiomics analysis reveals the mechanisms underlying the different floral colors and fragrances of Rosa hybrida cultivars.

The color and fragrance of rose flowers affect their commercial value. However, several rose varieties with new floral colors developed by the bud mutation method lost their fragrance during the breeding process, raising the question: Is there a relationship between floral color and aroma traits? Rose cultivar 'Yellow Island' (YI) with intensely aroma and yellow petals, while its bud mutant 'Past Feeling' (PF) with light aroma and pink petals mixing some yellow, two cultivars were used to explore this question using multiomics approaches. We investigated the genomic polymorphisms between PF and YI by whole-genome resequencing. 71 differentially abundant metabolites and 155 related differentially expressed genes identified in petals between PF and YI. From this, we constructed a model of metabolic changes affecting floral color and fragrance integrating shikimate, terpenoid, carotenoid, and green leaf volatile metabolites and predicted the associated key genes and transcription factors. This study provides a reference for understanding the molecular mechanism of variation in rose floral color and aroma traits.