Metabolite Profiles Provide Insights into Underlying Mechanism in Bupleurum (Apiaceae) in Response to Three Levels of Phosphorus Fertilization

Abstract

Phosphorus (P) deficiency affects plant yield and quality, yet at the same time, excessive phosphorus application does not necessarily promote the growth of plants. How to maintain a balance between biomass accumulation and phosphorus application is a problem. Therefore, the purpose of this research was to explore the relationship between yield and quality of Bupleurum and phosphorus fertilization, based on three phosphorus fertilization levels (20 kg∙ha−1; 10 kg∙ha−1; and 0 kg∙ha−1). We adopted gas chromatography-mass spectrometry to assess the response of primary metabolites of different plant tissues (flowers, main shoots, lateral shoots and roots) to phosphorus fertilization. At the same time, high-performance liquid chromatography was used to quantify saikosaponin A and saikosaponin D, the main active ingredients of Bupleurum. Our research showed that low phosphorus level application has a positive impact on the yield and quality of Bupleurum, especially the above-ground parts increasing the fresh weight of flowers and lateral shoots and the length of main shoots, and moreover, increasing the saikosaponins content in all above-ground parts while decreasing the content in roots which show no significance increase in fresh weight and length. However, high phosphorus level showed a negative impact as it decreases the saikosaponins content significantly in flowers and roots. Furthermore, phosphorus application changed the proportion of saikosaponins, promoting the content of saikosaponin A and inhibiting the content of saikosaponin D in most organs of Bupleurum. Therefore, we can say that high phosphorus application is not preferable to the yield and quality of Bupleurum. To identify the metabolic pathways and special key metabolites, a total of 73 metabolites were discovered, and four differential metabolites—ether, glycerol, chlorogenic and L-rhamnose—were considered to be the key metabolites of Bupleurum’s response to phosphorus fertilization. Furthermore, Bupleurum’s response to phosphorus fertilization was mainly related to metabolic pathways, such as starch and sucrose metabolism and galactose metabolism. Under the phosphorus level, the content of sugars, organic acids and their derivatives, polyols and their derivatives and alkyl were upregulated in flowers. Furthermore, the contents of compounds in the main shoot and lateral shoots showed the same upward trend, except glycosides and polyols and their derivatives.

Exogenous regulation of macronutrients promotes the accumulation of alkaloid yield in anisodus tanguticus (Maxim.) pascher

“…These results indicate that low-concentration phosphorus addition is more effective in promoting the accumulation of alkaloids in the aboveground parts of A. tanguticus . This phenomenon has also been observed in Bupleurum chinense , Dendrobium officinale , and Artemisia annua [ 52 , 88 ], where low phosphorus enhances the production of certain secondary metabolites in plants. This is attributed to the complex regulation of phosphorus entry into the plant body through gene expression networks, with low phosphorus stress upregulating the genes of key enzymes in the biosynthesis of secondary metabolite [ 88 , 89 ].…”

“…In summary, the results of this study reveal the regulatory role of phosphorus in the growth and biomass allocation of A. tanguticus . Phosphorus has also been found to play a crucial role in the healthy development of roots and biomass accumulation in medicinal plants such as Lupinus angustifolius , Dendrobium officinale , and Bupleurum chinense [ 45 , 49 , 52 ]. Previous studies have demonstrated that appropriate phosphorus addition helps improve the quality of medicinal plants while ensuring economic yield [ 86 , 87 ].…”

“…Confronted with this limitation (phosphorus deficiency), plants have evolved various developmental, biochemical, and symbiotic adaptation strategies, resulting in the accumulation of specific secondary metabolites [ 51 ]. Low phosphorus, for example, makes Bupleurum chinense make more saponins, increases the amount of flavonoids (mainly kaempferol and quercetin) in the roots of Cajanus cajan and Pak choi , and makes Dendrobium officinale store more alkaloids and polysaccharides [ 49 , 52 , 53 ]. Consequently, carefully considering and applying phosphorus in the cultivation of medicinal plants can foster robust plant growth and enhance the yield and quality of medicinal herbs.…”

Climate-Resilient Microbial Biotechnology: A Perspective on Sustainable Agriculture

“…In barley plants, glucose and fructose contents were maximized, whereas dehydro-ascorbate rates were reduced [103]. In general, 84 primary metabolites were detected from the transgenic plant's samples containing amino acid compounds, sugars, organic acids, polyols, and various lipid groups [104].…”

Transcriptome Level Reveals the Triterpenoid Saponin Biosynthesis Pathway of Bupleurum falcatum L.

“…Different genotypic varieties of Bupleurum plants differ significantly in the content and proportion of SSs [ 5 , 6 ], which are regulated by interior factors, e.g., growth stage, root structure, and environmental conditions, such as drought, light deficiency, and fertility [ 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. SSs are mainly in the pericycle and primary phloem in young roots, while in mature roots, they were mainly concentrated in the secondary phloem and vascular cambium [ 14 ].…”