METABOLIC STRATEGIES IN POLYGONATUM: GROWTHSTRESS TRADE-OFF REVEALED VIA MULTI-OMICS

As an emerging ideal crop, Polygonatum is receiving increasing attention. Polygonatum kingianum var. grandifolium (HBES) and Polygonatum sibiricum Red (SXHZ) are two Polygonatum ecotypes with contrasting traits; HBES shows significantly higher biomass and polysaccharide content than SXHZ. To investigate the underlying molecular mechanisms, a comparative metabolomic and transcriptomic analysis was conducted. The results revealed significant ecotypic differentiation in the organic acid metabolic pathway. HBES exhibited a “growth-type” metabolic pattern, characterized by a marked enrichment of carbon flux into the tricarboxylic acid (TCA) cycle. This was evidenced by increased accumulation of key intermediates. such as succinic acid and α-ketoglutaric acid, supporting highly efficient energy metabolism that fuels robust biomass accumulation and polysaccharide synthesis. In contrast, SXHZ enhanced the shikimic acid pathway, directing carbon flux toward secondary metabolites synthesis and forming a “defense-type” metabolic pattern. This strategy prioritizes stress resistance but also limits biomass production. Transcriptome analysis further identified multiple key genes involved in regulating this differential carbon flow allocation. These distinct carbon allocation strategies are likely stable genetic traits shaped by their native soil environments, ultimately defining the architecture and function of their organic acid metabolic networks. This study, from an organic acid metabolism perspective, reveals critical differences in central carbon metabolism among Polygonatum ecotypes, providing a theoretical basis for breeding high-yield, high-resistance varieties.