Recently, the team led by Professor Jia Guixia from the School of Landscape Architecture at Beijing Forestry University published a research paper titled "The Coordinated Interaction or Regulation Between Anthocyanin and Carotenoid Pathways in OT Hybrid Lilies Based on Metabolome and Time-Course Transcriptomics Analysis" in Industrial Crops and Products. This journal is highly regarded in Agricultural and Forestry Sciences and ranks among the top tiers according to the Chinese Academy of Sciences.

Flower color is an important visual signal to attract pollinators and ensure reproduction, which has great commercial and economic value for horticultural plants. Anthocyanins and carotenoids are the two main pigments that form the rich colors of flowering plants. In many crops, the combination and content of anthocyanins and carotenoids could make fruits, petals and other organs form rich colors to improve the popularity in the market, such as orange, pink, purple, purplish red, and brown, and this phenomenon has been reported in apples, capsicum, rice, rosa and chrysanthemum; . Lilium spp. is one of the most important edible and ornamental crops in the world, which has rich flower color, including red, purple, yellow, orange and other colors except blue. In the hybrid breeding of lily, when anthocyanins and carotenoids coexist, the color of the offspring would produce abundant changes compared with the parents.

To explore the co-regulatory mechanism of the two types of pigments, the parents with anthocyanin pathway (L. speciosum) and carotenoid pathway (L. henryi) were used respectively and the offspring 'Black Beauty' with both two types of pigments obtained by hybridization as the research materials, through metabolome, RNA-seq, time-course transcriptomics analysis, and microscopic analysis to reveal the dynamic changes of pigmentation.

The metabolome analysis results suggest that variations in the levels of β-citraurin and lutein in carotenoids, as well as peonidin-3-O-rutinoside and cyanidin-3-O-glucoside in anthocyanins, were the primary factors leading to the color disparities between offspring and parents. Then, metabolic pathways for the potential co-regulatory networks of dual pigment pathways were built by analysis of time-ordered gene co-expression networks (TO-GCNs) in 'Black Beauty'. Through the analysis of the subnetwork, it was found that WRKY, MYB, NAC, IAA, MADS transcription factor families were potential key transcription factor families. In addition, the co-regulatory networks with PSY, PDS, LCYE and C4H, CHI, FLS, ANS, DFR and other structural genes were constructed. The results showed that carotenoids may affect anthocyanin content through promoting light capture and multiple transcription factors coordinate the isoprenoid pathway and the phenylpropanoid pathway. Furthermore, this study holds significant theoretical importance for exploring the balance between different secondary metabolic pathways of ornamental plants.

Yu Pengcheng, a doctoral candidate at the School of Landscape Architecture is the lead author of the paper. Professor Jia Guixia serves as the corresponding author and has been dedicated to the long-term collection, evaluation, and breeding of germplasm resources for ornamental plants such as lilies, along with his team. Their work has been recognized with the Second Prize of the Beijing Science and Technology Progress Award and has resulted in numerous research papers published in leading academic journals including Industrial Crops and Products, Scientia Horticulturae, Plant Physiology and Biochemistry, BMC Plant Biology, and Chinese Journal of Horticulture.

This work was funded by National Key Research and Development Project of China (2023YFD1200105) and National Key R&D Project of China (2019YFD1000400).

Link: https://doi.org/10.1016/j.indcrop.2024.119795

Written by Yu Pengcheng
Translated and edited by Song He
Reviewed by Yu Yangyang