Paeonia species are important ornamental plants,including three types:tree peony,herbaceous peony,and Itoh hybrid peony.Paeonia with yellow color is desired and becoming popular.However,the chemical mechanism of the f...Paeonia species are important ornamental plants,including three types:tree peony,herbaceous peony,and Itoh hybrid peony.Paeonia with yellow color is desired and becoming popular.However,the chemical mechanism of the formation of yellow flowers in Paeonia is still unclear.In this study,14 representative samples were selected:four samples of three species of Paeonia,four herbaceous peony cultivars,three lutea hybrid tree peony cultivars,and three Itoh hybrid peony cultivars.The petal extracts of the samples were determined by HPLC-DAD and HPLCQ-TOF-MS/MS.In total,29 flavonoids were isolated and identified,including 28 flavonol glycosides and one chalcone derivative.There were significant differences in the composition and content of flavonoids in petals of different cultivars(species).The total content of flavonoids was between 19.430 and 143.043 mg·g^−1 DW.Flavonol glycosides were detected in all samples.Chalconaringenin 2′-O-glucoside was detected from one herbaceous peony cultivar‘Golden Wheel’lutea hybrid tree peony cultivars,and Itoh peony cultivars.The content of chalconaringenin 2′-O-glucoside in the samples was more than 43% of total flavonoids.The pigment type and content of lutea hybrid tree peonies and Itoh hybrid peonies are similar.Total flavonoids,especially quercetin 3-O-galloylglucoside and chalconaringenin 2′-O-glucoside contribute greatly to the formation of yellow flowers of Paeonia.The results of this study provide a comprehensive understanding of the chemical mechanism for yellow flower coloration of Paeonia,and lay the foundation for yellow flower breeding of Paeonia.展开更多
Tree peony cultivars with yellow flowers are rare and valuable,but the molecular mechanism of pigment accumulation is not clear.In this study,the petal transcriptome of three developmental stages were sequenced to det...Tree peony cultivars with yellow flowers are rare and valuable,but the molecular mechanism of pigment accumulation is not clear.In this study,the petal transcriptome of three developmental stages were sequenced to determine the differentially expressed genes(DEGs)regulating yellow flowers color.The results showed that 10,842 and 12,022 DEGs were screened in stage 1 vs.stage 2 and in stage 2 vs.stage 3,respectively.Through analysis of flavonoid structural genes(FSGs),we found that the transcription level of DFR was very low in the three developmental stages.In a small group of cultivars,the DFR transcription level of red flowers was 862 times higher than that of yellow flowers.These data suggested that the flavonoid pathway is interrupted in the later stage due to the low transcriptional level of DFR,which limits the biosynthesis of anthocyanins in yellow flowers.The transcription levels of F3’H and FLS were upregulated from stage 1 to stage 2,while those of CHI and FLS were downregulated from stage 2 to stage 3.In addition,67 MYBs and 44 bHLHs showed similar transcription profiles with different members of FSGs.The results deepen our understanding of the molecular mechanism of yellow pigment accumulation in tree peony.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31772350).
文摘Paeonia species are important ornamental plants,including three types:tree peony,herbaceous peony,and Itoh hybrid peony.Paeonia with yellow color is desired and becoming popular.However,the chemical mechanism of the formation of yellow flowers in Paeonia is still unclear.In this study,14 representative samples were selected:four samples of three species of Paeonia,four herbaceous peony cultivars,three lutea hybrid tree peony cultivars,and three Itoh hybrid peony cultivars.The petal extracts of the samples were determined by HPLC-DAD and HPLCQ-TOF-MS/MS.In total,29 flavonoids were isolated and identified,including 28 flavonol glycosides and one chalcone derivative.There were significant differences in the composition and content of flavonoids in petals of different cultivars(species).The total content of flavonoids was between 19.430 and 143.043 mg·g^−1 DW.Flavonol glycosides were detected in all samples.Chalconaringenin 2′-O-glucoside was detected from one herbaceous peony cultivar‘Golden Wheel’lutea hybrid tree peony cultivars,and Itoh peony cultivars.The content of chalconaringenin 2′-O-glucoside in the samples was more than 43% of total flavonoids.The pigment type and content of lutea hybrid tree peonies and Itoh hybrid peonies are similar.Total flavonoids,especially quercetin 3-O-galloylglucoside and chalconaringenin 2′-O-glucoside contribute greatly to the formation of yellow flowers of Paeonia.The results of this study provide a comprehensive understanding of the chemical mechanism for yellow flower coloration of Paeonia,and lay the foundation for yellow flower breeding of Paeonia.
基金funded by Henan Province Science and Technology Breakthrough Project(212102110015)and the Key Scientific Research Projects of Colleges and Universities in Henan Province(21A180018).
文摘Tree peony cultivars with yellow flowers are rare and valuable,but the molecular mechanism of pigment accumulation is not clear.In this study,the petal transcriptome of three developmental stages were sequenced to determine the differentially expressed genes(DEGs)regulating yellow flowers color.The results showed that 10,842 and 12,022 DEGs were screened in stage 1 vs.stage 2 and in stage 2 vs.stage 3,respectively.Through analysis of flavonoid structural genes(FSGs),we found that the transcription level of DFR was very low in the three developmental stages.In a small group of cultivars,the DFR transcription level of red flowers was 862 times higher than that of yellow flowers.These data suggested that the flavonoid pathway is interrupted in the later stage due to the low transcriptional level of DFR,which limits the biosynthesis of anthocyanins in yellow flowers.The transcription levels of F3’H and FLS were upregulated from stage 1 to stage 2,while those of CHI and FLS were downregulated from stage 2 to stage 3.In addition,67 MYBs and 44 bHLHs showed similar transcription profiles with different members of FSGs.The results deepen our understanding of the molecular mechanism of yellow pigment accumulation in tree peony.
