Comparative Analysis of Microbial Community Dynamics in Fusarium Wilt-Infected and Healthy Tomato Rhizospheres Across Plant Developmental Stages (PRJCA043830)
Tomato (Solanum lycopersicum) is severely affected by Fusarium wilt, yet the dynamics of root-associated microbial communities linked to disease across growth stages remain unclear. This study used 16S rDNA and ITS amplicon sequencing to compare bacterial and fungal communities in rhizosphere soils of healthy and diseased tomato plants at single-truss (early) and 4-5-truss (late) fruiting stages. Healthy plants at the early stage exhibited higher bacterial diversity, while diseased plants showed increased bacterial richness and diversity in late stages. Bacterial genera composition was similar between healthy and diseased samples, and no well-recognized pathogenic bacteria were found. In contrast, fungal communities in healthy samples displayed greater richness/diversity at both stages. The beneficial genus Mortierella was enriched in healthy roots, whereas pathogenic genera (Plectosphaerella, Fusarium, Neocosmospora) dominated diseased soils. Co-occurrence analysis showed that these three pathogenic genera were less abundant in early- than in late-diseased samples, with their synergistic interactions weakening at later stages, likely due to overabundance disrupting fungal community balance. Pathogen isolation confirmed Fusarium oxysporum enrichment in diseased soils. These findings revealed dynamic shifts in rhizosphere microbial communities linked to tomato Fusarium wilt across plant developmental stages, underscoring the critical role of pathogenic fungi in disease progression during different growth phases.