Integrated Transcriptomic and Metabolomic Analyses Reveal Coordinated Phosphorus Deficiency Responses and Enhanced Rubber Biosynthesis in Taraxacum kok-saghyz

Phosphorus deficiency (PD) is a critical macronutrient stress that profoundly influences plant growth, root architecture, and metabolic homeostasis. Taraxacum kok-saghyz (TKS), an emerging alternative rubber-producing crop, exhibits remarkable adaptability to nutrient-poor soils, yet the molecular basis of its response to PD remains largely unknown. Here, we integrated physiological, biochemical, transcriptomic, and metabolomic analyses to elucidate the adaptive mechanisms of TKS roots under phosphorus limitation. PD treatment resulted in shorter primary roots, increased lateral root proliferation and root hair density, and significant alterations in nutrient and anthocyanin contents. Combined omics analyses revealed extensive reprogramming of gene expression and metabolism, particularly in pathways related to phenylpropanoid biosynthesis, glutathione metabolism, and isoprenoid biosynthesis. Phosphorus deprivation triggered oxidative stress, which was counterbalanced by activation of the ascorbate-glutathione cycle, while genes associated with the mevalonate pathway and natural rubber synthesis were transcriptionally enhanced. These findings systematically uncover the coordinated molecular and physiological adaptations that underpin TKS resilience to low phosphorus, providing critical insights for improving phosphate use efficiency and enhancing natural rubber yield in industrial crops.