Differences in microbial community structure and soil nutrients between healthy and diseased soils of Zingiber officinale

Abstract

To investigate the differences in soil nutrients and microbial community structure in the rhizosphere between healthy and diseased Zingiber officinale plants, soil samples were collected from healthy root-zone soil (ZSH), healthy rhizosphere soil (RSH), diseased root-zone soil (ZSD), and diseased rhizosphere soil (RSD). Diseased soils had significantly higher pH values, whereas RSH showed the strongest acidity. Moreover, pH, AN, and AK contents in diseased soils were significantly higher than those in healthy soils, while SOM and AP were significantly lower. The -diversity of microbial communities in diseased soils was significantly reduced, and the community structure was distinctly differentiated from that of healthy soils. In diseased soils, the abundance of potential pathogenic taxa such as Ralstonia solanacearum increased significantly, while beneficial genera such as Bradyrhizobium decreased. Redundancy analysis and correlation analysis indicated that soil pH, AN, SOM, and AP were the major environmental factors driving changes in microbial community structure. The occurrence of soil-borne diseases in Zingiber officinale is closely associated with soil nutrient imbalance and disruption of microbial community structure. The study identified candidate microbial taxa (e.g., beneficial Sphingomonas, Streptomyces) and key soil properties (pH, available nitrogen) that differentiate healthy from diseased ginger soils. Together, these findings provide a theoretical basis for improving diseased soils through microecological regulation strategies, and also serve as a foundation for generating testable hypotheses in future hypothesis-driven research on ginger soil-borne disease suppression.