Balance of Carotenoid Synthesis and Degradation Contributes to the Color Difference between Chinese Narcissus and Its Yellow-Tepal Mutant

Chinese narcissus (Narcissus tazetta var. chinensis) was introduced to China 1300–1400 years ago, and has grown naturally in southeastern China. It is a popular traditional potted flower well-known flowering bulb cultivated worldwide with only two white-tepal triploid cultivars, ‘Jinzhan Yintai’ ‘Yulinglong’. Recently, mutant yellow tepals observed promptly became popular. To clarify the key pigment for color difference its molecular mechanism of accumulation, we conducted metabolite analysis comparative transcriptome on yellow-flowered mutant. The results showed that there no significant total flavonoid content between Yintai’, whereas carotenoid more than 10-fold higher Yintai’. Based RNA-sequencing results, sixty-four unigenes, corresponding 29 enzymes associated biosynthesis pathway, were analyzed detail. A KEGG pathway enrichment analysis, conjunction quantitative real-time PCR data, revealed opposite gene expression mode pathway. Compared Yintai ’, PSY PDS up-regulated three mid-flowering stages mutant, NCED genes strongly down-regulated, which likely contributed accumulation chromoplasts