Revealing the Impact of the Environment on Cistanche salsa: From Global Ecological Regionalization to Soil Microbial Community Characteristics

To understand the regulatory relationship between the environment and Cistanche salsa, here we integrated the macro- and microdimension methods. From a macroperspective, the MaxEnt model indicated that countries along the Belt and Road Initiative, such as China, Egypt, and Libya, were particularly suitable for growth of C. salsa from ancient times (Last Glacial Maximum and mid-Holocene) to the future (2050 and 2070). The Jackknife test revealed that precipitation is an important ecological factor that affects C. salsa's distribution. From a microperspective, 16S rRNA amplicon sequencing data showed that the soil microbial communities of three ecotypes (desert-steppe, grassland, and gravel-desert) were significantly different (p < 0.001). Core microbiome analysis demonstrated that the bacterial genera Arthrobacter, Sphingomonas, and Bacillus were enriched core taxa of C. salsa. LEfSe and random forest were used to excavate the Gillisia (desert-steppe), Flavisolibacter (grassland), and Variibacter (gravel-desert) as biomarkers that can distinguish among microbial communities from the three ecotypes. The prediction profile showed that the metabolic function of the microbial community was enriched in metabolic pathways and environmental information processing. Correlation analyses revealed that the altitude, precipitation of the warmest quarter (bio18), mean diurnal range (bio2), and mean temperature of the warmest quarter (bio10) were important ecological factors that affect the composition of soil microbial communities. This work provided new insights into the regulatory relationship among the suitable distribution of C. salsa, soil microbial communities, and ecological drivers. Moreover, it deepened the understanding of the interaction between desert plants and ecological factors in arid environments.