Abstract:
Objective The purpose of this study was to investigate the effects of different soil types on the physicochemical properties of rhizosphere soil and the diversity of bacterial communities on the occurrence of bacterial wilt in flue-cured tobacco.
Method The occurrences of tobacco blight were investigated in different soil types, the physicochemical properties and bacterial community diversity of the inter-root soils of diseased and healthy tobacco plants were tested, and the relationship between the two and the occurrence of tobacco blight was analyzed.
Result The study showed that there are significant differences in the incidence and disease index of tobacco bacterial wilt under different soil types. The incidence and disease index of bacterial wilt were the most severe in submerged paddy soil (A), while the incidence was relatively low in saline paddy soil (S), and the disease index was the lowest in yellow red soil (I). There are significant differences in the physical and chemical properties of soil and the diversity of bacterial communities at the root zone between diseased and healthy tobacco plants. These differences varied depending on the type of soil. The differences in physical and chemical properties of soil and the diversity of bacterial communities at the root zone between diseased and healthy tobacco plants were significant. These differences varied depending on the type of soil. In healthy soil, the bacteria number of Prevotella and Sphingomonas were negatively correlated with the incidence (DI) of the disease. While in diseased soil, the bacteria number of Nitrospirae and Rickettsiales was positively correlated with the incidence (DI) of the disease.
Conclusion The healthy soil of saline-alkali paddy soil can improve the soil bacterial community in tobacco fields, effectively inhibit the occurrence of tobacco bacterial wilt by reducing the reproduction of pathogenic bacteria of Nitrospirae. While, the diseased soil of submerged paddy soil can promote the growth of pathogenic bacteria of Nitrospirae, leading to an increase in the incidence of tobacco bacterial wilt.