Analysis of the Changing Trend of Microbial Community in Rhizosphere Soil during Different Stages of Tobacco Bacterial Wilt Infection

In order to clarify the interaction between microecology and bacterial wilt, the changing trend of bacterial and fungal communities in rhizosphere soil during different stages of tobacco bacterial wilt infection was explored by ampliton sequencing technology. The results indicated that compared with pre-transplantation, Sobs, shannon index and OTU number of bacterial communities in rhizosphere soil at 75 d and 100 d post-transplantation from field with severe tobacco bacterial wilt were significantly decreased, while the diversity indexes of fungal communities showed no significant change. During the occurrence of tobacco bacterial wilt, the relative abundance of some pathogenic microorganisms (Ralstonia, Fusarium, etc.) and beneficial microorganisms (Sphingomonas, Gemmatimonas, Pseudomonas, Lysobacter, Streptomyces, Trichoderma, Gibberella, Chaetomium, etc.) increased. Compared with pre-transplantation, the bacterial community structure in rhizosphere soil from field with severe tobacco bacterial wilt has been significantly changed at 75 d and 100 d post-transplantation, and the fungal community structure in rhizosphere soil has been significantly changed at 50 d and 75 d post-transplantation.