S01 - Session P6 - Molecular analysis of double mutants for flower fragrance and coloration in fragrant cyclamen

Authors: Yusuke Akita *, Riho Mikami, Parisa Loetratsami, Shiho Morimura

Flower fragrance and coloration are excellent traits in flowering plants . We previously produced the white-flowered fragrant cyclamen mutant 'Kinu-no-mai' (KN) from the purple-flowered cultivar 'Kokou-no-kaori' (KO) by ion-beam irradiation. HPLC analysis showed that malvidin 3,5-diglucoside is the main component of flower coloration in KO, while, in contrast, no anthocyanins were found in the petals of KN. In addition, we analyzed and compared the aroma component of KO and KN using GC/MS, which did not indentify any significant differences for other monoterpenes and sesquiterpenes, whereas the aromatic compounds cinnamaldehyde, hydro-cinnamic alcohol and cinnamyl alcohol were detected only in KO. From these results, we expected that the double mutation of anthocyanin and aroma component biosynthesis pathways would have occurred in KN. To determine the mutation factors, we performed am RNA-seq analysis and compared the expressions of several genes that might be involved in flower coloration and fragrance between KO and KN. We found that the expression of new glutathione S- transferase ( CkoGST ), which has not been reported previously, was significantly, but weakly present in the petals of KN. Moreover, in KN, some genes that would be related to cinnamyl alcohol biosynthesis, showed lower expression compared with those of KO. Our study will contribute to the breeding of new flowers with excellent fragrance and new colors.