Combined transcriptome and metabolome analysis reveal that the white and yellow mango pulp colors are associated with carotenoid and flavonoid accumulation, and phytohormone signaling.

ABSTRACT

Mango (Mangifera indica L.) is a widely appreciated tropical fruit for its rich color and nutrition. However, knowledge on the molecular basis of color variation is limited. Here, we studied HY3 (yellowish-white pulp) and YX4 (yellow pulp), reaped with 24 h gap from the standard harvesting time. The carotenoids and total flavonoids increased with the advance of harvest time (YX4 > HY34). Transcriptome sequencing showed that higher expressions of the core carotenoid biosynthesis genes and flavonoid biosynthesis genes are correlated to their respective contents. The endogenous indole-3-acetic acid and jasmonic acid contents decreased but abscisic acid and ethylene contents increased with an increase in harvesting time (YX4 > HY34). Similar trends were observed for the corresponding genes. Our results indicate that the color differences are related to carotenoid and flavonoid contents, which in turn are influenced by phytohormone accumulation and signaling.