Plant metabolites are important for
plant development and
human health .
Plants of
celery (Apiumgraveolens L.) with different-colored petioles have been formed in the
course of long-term evolution. However, the composition, content distribution, and mechanisms of accumulation of metabolites in different-colored petioles remain elusive. Using ultra-
high performance liquid chromatography -
tandem mass spectrometry (UHPLC-MS/MS), 1159 metabolites, including 100
lipids , 72
organic acids and derivatives, 83 phenylpropanoids and
polyketides , and several
alkaloids and
terpenoids , were quantified in four
celery cultivars, each with a different petiole
color . There were significant differences in the types and contents of metabolites in
celery with different-colored petioles, with the most striking difference between green
celery and
purple celery , followed by
white celery and green
celery . Annotated
analysis of
metabolic pathways showed that the metabolites of the different-colored petioles were significantly enriched in
biosynthetic pathways such as
anthocyanin ,
flavonoid , and
chlorophyll pathways, suggesting that these
metabolic pathways may
play a key
role in determining petiole
color in
celery . The content of
chlorophyll in green
celery was significantly higher than that in other
celery cultivars, yellow
celery was rich in
carotenoids , and the content of
anthocyanin in
purple celery was significantly higher than that in the other
celery cultivars. The
color of the
celery petioles was significantly correlated with the content of related metabolites. Among the four
celery cultivars, the metabolites of the
anthocyanin biosynthesis pathway were enriched in
purple celery . The results of
quantitative real-time polymerase chain reaction (qRT-
PCR ) suggested that the differential expression of the
chalcone synthase (CHS)
gene in the
anthocyanin biosynthesis pathway might
affect the
biosynthesis of
anthocyanin in
celery . In addition,
HPLC analysis revealed that cyanidin is the main pigment in
purple celery . This study explored the differences in the types and contents of metabolites in
celery cultivars with different-colored petioles and identified key substances for
color formation. The results provide a theoretical basis and technical support for genetic improvement of
celery petiole
color .