Abstract:

To explore the effects of different crop rotations on root rot of Baitiao Codonopsis pilosula and its rhizosphere soil fungal community，this study used high-throughput sequencing technology to analyze the composition spectrum of fungal microbiota in the rhizosphere soil of Baitiao Codonopsis pilosula under different crop rotations， including maize-wheat-Codonopsis pilosula（C1），wheat-broad bean-Codonopsis pilosula（C2），potato-wheat-Codonopsis pilosula（C3），and Astragalus membranaceus-Codonopsis pilosula-Codonopsis pilosula（C4）. The results showed that Ascomycota was the dominant phylum in all crop rotations. The relative abundances of Mortierellomycota，Mortierellomycetes，and Humicola in healthy plants were higher than those in diseased plants across all crop rotations，indicating that the soil fungal community abundance of Baitiao Codonopsis pilosula plants with root rot showed a decreasing trend. FUNGuild predicted the nutritional types and functional groups of rhizosphere soil fungi，revealing that the relative abundance of plant pathogens in all crop rotations was consistently higher in diseased plants than in healthy plants. Comparing the incidence rate of all crop rotations，we found that the incidence rate of root rot of wheat-broad bean-Codonopsis pilosula was the lowest，followed by maize-wheat-Codonopsis pilosula. Overall，crop rotation of wheat-broad bean-Codonopsis pilosula can effectively reduce the incidence of root rot，which may be related to increasing soil microbial abundance.

Key words: Baitiao Codonopsis pilosula, root rot, rhizosphere soil, fungal community