Integrating flavonoid metabolome and RNA-seq data unveil flower color variation in Bombax ceiba.

Floral pigmentation is essential for ornamental species. This investigation utilized flower tissues from five distinct color phenotypes (dark red, red, orange-red, orange-yellow, yellow) of Bombax ceiba to conduct targeted flavonoid metabolomics and RNA sequencing analyses, resulting in the identification of 137 metabolites and 44,725 genes. The results indicated that the expression levels of BcCHSs, BcCHIs, BcF3'5'Hs, BcDFRs, and BcLDOXs were significantly lower in yellow flowers compared to their counterparts of other colors. This reduction led to decreased concentrations of intermediates in the anthocyanin biosynthetic pathway, including naringenin chalcone, naringenin, dihydromyricetin, leucodelphinidin, and delphinidin, which corresponded to a reduction in red pigmentation and an enhancement of yellow pigmentation in the floral phenotype of Bombax ceiba. This dataset represents a substantial resource for researchers aiming to elucidate the mechanisms underlying floral pigmentation variation and to facilitate advancements in the domain of plant genetic engineering.