| To explore the effects of returning sweet potato vines to the field on soil microbial diversity and fertility, soil nutrients and microbial diversity were measured and analyzed in a long-term fixed-site experiment under wheat-sweet potato rotation over five consecutive years. The results showed that returning sweet potato vines to the field significantly reduced soil pH and markedly improved soil fertility. In terms of soil microbial diversity, returning sweet potato vines to the field significantly increased the relative abundances of Proteobacteria, Actinobacteria, and Bacteroidetes in the bacterial community, especially the relative abundances of MND1,Haliangium, and Ramlibacter. It also increased α-diversity indices, including the Chao1, Observed species, and Shannon indices. Meanwhile, under the vine-returning treatment, the relative abundance of Ascomycota in the fungal community increased significantly, whereas the relative abundances of Basidiomycota and Glomeromycota decreased significantly, especially those of harmful groups such as Humicola, Ceratobasidium, Didymella, and Meloidogyne. The Chao1 and Observed species indices also increased. In summary, returning sweet potato vines to the field can significantly improve the diversity of bacterial and fungal communities in soil and provide a feasible approach for alleviating obstacles associated with continuous sweet potato cropping. |
