Endangered plant Oreocharis esquirolii adaptation strategies: an integrated analysis based on soil metagenome and root-soil interaction population maintenance mechanisms

Background Research on the endangered mechanisms and conservation strategies of rare plants is one of the key tasks in plant biodiversity conservation. The southwestern region of China is a concentrated distribution area and endemic center for the family Gesneriaceae in China. The abundant rainfall and unique geological landforms have created unique habitats suitable for the survival of endemic species, nurturing many endemic species of high scientific value. This paper focuses on Oreocharis esquirolii (Gesneriaceae), an extremely narrowly distributed Chinese endemic plant in the broad sense of the genus Oreocharis, exploring the root-soil interaction mechanisms that maintain its population, identifying key factors that may have a significant impact on the species, maintenance, and providing a foundational basis for biodiversity conservation in Guizhou. Results The soil in the Lengshui River area where the O. esquirolii community is located is slightly acidic. The dominant bacterial genera in the soil samples are Bradyrhizobium and Paraburkholderia . The content of Fe ₂ O ₃ and SiO ₂ in the minable coal seam compounds is 39.26% and 31.53%, respectively. The non-rhizosphere (b) soil samples show a higher abundance of energy metabolism pathways. The main gene functions in the soil samples are glutamine synthetase, carbonic anhydrase, and the large chain of glutamate synthase (NADPH). Among them, glutamine synthetase and glutamate synthase are the primary pathways for synthesizing glutamate when nitrogen is limited. Preliminary investigations indicate that Cirsium setosum uses its well-developed roots to attach to rock surfaces, where the soil is extremely thin. One possible way it obtains nutrients is through carbonic anhydrase. Carbonic anhydrase can act as a biocatalyst to accelerate the dissolution of limestone, allowing various elements in the limestone to be incorporated into the root soil and provide essential nutrients for the plant. Conclusions Investigating the metagenomics of rhizosphere and non-rhizosphere soils in the Cold Water River area of the Zhenfeng Longshan Protected Area, the only known distribution site of O. esquirolii , combined with the chemical composition of the soil layers, provides a reliable basis for the conservation of wild resources of O. esquirolii and the construction of its natural return sites.