Carbon and nitrogen metabolism under nitrogen variation affects flavonoid accumulation in the leaves of Coreopsis tinctoria

PeerJ

article

Zhiyuan Li¹  Hong Jiang¹  Huizhuan Yan¹  Xiumei Jiang¹  Yan Ma²  Yong Qin¹ 

[1] College of Forestry and Horticulture, Xinjiang Agriculture University;Institute of Agricultural Mechanization, Xinjiang Academy of Agricultural Sciences

关键词: Nitrogen;    C. tinctoria;    Carbon metabolism;    Nitrogen metabolism;    Flavonoid accumulation;   

DOI  :  10.7717/peerj.12152

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Flavonoids are phytochemicals present in medicinal plants and contribute to human health. Coreopsis tinctoria, a species rich in flavonoids, has long been used in traditional medicine and as a food resource. N (nitrogen) fertilization can reduce flavonoid accumulation in C. tinctoria. However, there is limited knowledge regarding N regulatory mechanisms. The aim of this study was to determine the effect of N availability on flavonoid biosynthesis in C. tinctoria and to investigate the relationship between C (carbon) and N metabolism coupled with flavonoid synthesis under controlled conditions. C. tinctoria seedlings were grown hydroponically under five different N levels (0, 0.625, 1.250, 2.500 and 5.000 mM). The related indexes of C, N and flavonoid metabolism of C. tinctoria under N variation were measured and analysed. N availability (low and moderate N levels) regulates enzyme activities related to C and N metabolism, promotes the accumulation of carbohydrates, reduces N metabolite levels, and enhances the internal C/N balance. The flavonoid content in roots and stalks remained relatively stable, while that in leaves peaked at low or intermediate N levels. Flavonoids are closely related to phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), 4-coumarate: coenzyme A ligase (4CL), and chalcone-thioase (CHS) activity, significantly positively correlated with carbohydrates and negatively correlated with N metabolites. Thus, C and N metabolism can not only control the distribution of C in amino acid and carbohydrate biosynthesis pathways but also change the distribution in flavonoid biosynthesis pathways, which also provides meaningful information for maintaining high yields while ensuring the nutritional value of crop plants.

【 授权许可】

CC BY