Analysis of Fungal Community Characteristics in Roots and Rhizosphere Soil Between Healthy Tomato Plants and Plants Infected by Root-Knot Nematodes

Using ITS amplicon sequencing, the fungal communities of five sample types - disease roots infected by root-knot nematodes, root knots, soil from diseased root systems, healthy roots, and soil from healthy root systems - were studied. The results indicated that with root-knot nematode infection, the dominant fungal phyla in tomato roots gradually shifted from Glomeromycota to Ascomycota. At the order level, the abundance of Glomerales fungi decreased, while the abundance of Mucorales, Saccharomycetales, Pleosporales, and Sordariales fungi increased. The dominant phyla in the root soil shifted from Basidiomycota to Ascomycota, with Mucorales as the dominant order. α diversity shows that after root-knot nematode infection, the richness and diversity of fungal communities in the root soil increased, while the richness of fungal communities in tomato roots decreased. β diversity indicated significant differences in fungal abundance among the five sample groups. This demonstrates that root-knot nematode infection causes substantial changes in the fungal structure of tomato roots.