Astragalus mongholicus, a well-known traditional Chinese herbal medicine, has been widely used for more than 2000 years. Although previous studies have revealed that the medicinal quality of wild plants is superior to the cultivated plants, the regulatory mechanism responsible for the variations in metabolite accumulation between wild and cultivated A. mongholicus have not yet been conducted. Here, the roots and rhizosphere soils of cultivated, imitated wild and wild A. mongholicus were used for metabolite, transcript and microbiota analysis. The contents of calycosin-7-O-β-D-glucoside (CG) and astragaloside IV were achieved 0.47±0.02 mg/g and 1.17±0.06 mg/g in wild A. mongolicus, which were more than 1.49- and 1.98-fold higher compared to the cultivated A. mongolicus, respectively. Consistently, there were 424 genes differentially co-expressed at least two types of growth pattern, among which 23 genes (i.e. AmPAL, AmCHS, AmHMGS, AmSQE and AmOSC) directly involved in the biosynthesis of CG and astragaloside were significantly higher expressed in wild/imitated wild plants than in cultivated plants. The soil composition differed by region with higher organic matter, available nitrogen in wild regions, while lower pH, available phosphorus and potassium in cultivated regions. Meanwhile, the microbial diversity in wild rhizosphere were significantly lower than that in cultivated rhizosphere. Notably, the high abundance of biomarkers (i.e. Variovorax, Rhizobium and Lysobacter) were observed in wild rhizosphere, which indirectly boosted the metabolite accumulation in wild plant. Taken together, a regulatory model of soil-plant-microbe in A. mongolicus was established by integrating multi-omics analysis, which were of great guidance on the cultivation of A. mongolicus with high medicinal quality via targeted agricultural management.
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