Abstract:

Known as the“Queen of Flowers”，Rosa spp. boasts significant ornamental and commercial value attributed to its floral fragrance. Currently，most products derived from rose scent are dominated by the rose fragrance type sourced from R. damascena，while research on other fragrance types remains limited. R. gigantea，a species endemic to China，exhibits a distinctive aroma. Therefore，twelve progenies obtained from the hybridization of R. chinensis‘Old Blush’and R. gigantea were employed as experimental materials. Through integrated analyses of volatile metabolomics and histochemical staining techniques， the composition，genetic characteristics，and fragrance-releasing tissues of floral scent components in these progenies were systematically elucidated. The results demonstrated that a total of 39 primary aromatic compounds were identified in the progenies，predominantly terpenoids and phenylpropanoids. Among these，the differential content of eugenol served as the key criterion for progeny classification，displaying the genetic characteristics of a qualitative trait. Notably，neither the type nor the content of aromatic substances could effectively distinguish between double-petaled and single-petaled groups. Histochemical staining revealed that both the adaxial and abaxial epidermis of petals contained osmophore structures enriched with granular precursor substances，which function as the primary sites for fragrance emission. The progenies inherited the parental traits in terms of osmophore morphology and distribution，whereas the lipid release pattern exhibited paternal specificity.

Key words: Rosa gigantea, hybrid F₁ generation, floral fragrance components, fragrant parts