Seasonal dynamics of rhizosphere soil microbiome composition and diversity in Chinese Cunninghamia lanceolata in response to soilborne pathogen infection
The damage caused by soil-borne diseases in Cunninghamia lanceolata (Lamb.) Hook (Cupressaceae), commonly called the Chinese fir, has become increasingly severe in China in recent years. Due to the strong seasonal dependence of the occurrence and severity of these diseases, the ecological processes influencing changes in the composition and function of the plant microbiome during different seasons of pathogen infection have been rarely studied. This study compared the seasonal variations in soil physicochemical properties between the rhizosphere soils of healthy and diseased C. lanceolata in major production areas in China. It further explored the effects of root rot on the composition, structure, and ecological functions of rhizosphere microorganisms. The results demonstrated that seasonal variations significantly influenced the physicochemical properties and microbial composition of the rhizosphere soil in C. lanceolata affected by root rot. Microbiome analysis further confirmed that, within the same season, healthy C. lanceolata contained a greater abundance of ecologically beneficial microbial taxa in the rhizosphere soil compared to diseased trees. These microorganisms may function as bioprotectants. This study enhances our understanding of the structural and functional changes in the rhizosphere soil microbiome associated with soil-borne diseases and provides potential ecological management strategies to improve plant resistance to root rot.