Effects of antagonistic bacteria on tobacco wild fire and responses of phyllosphere microbiota

Abstract:

[Background] Tobacco wild fire is one of the main diseases on tobacco. It is a promising method to control tobacco wild fire with antagonistic bacteria. [Objective] To analyze the composition and diversity of microbial community in tobacco leaf, and explain the control effect of antagonistic bacteria on tobacco wild fire. [Methods] Three antagonistic groups were applied to tobacco, and the effects of antagonistic groups on the structure and diversity of tobacco leaf microbial community were analyzed by 16S rRNA gene high-throughput sequencing and bioinformatics.[Results] The control effect of antagonistic bacteria on tobacco wild fire reached 50.44%−68.58%. The community structure and composition of antagonistic groups had significant changes, was significantly higher community diversity, compared with the control group. After treatment with antagonistic flora, the proportion of tobacco leaf microflora, such as Pantoea, Stenotrophomonas and Pseudomonas, changed significantly, Bacillus and Stenotrophomonas increased by 3.9 and 7.02 times, respectively, compared with the control. The abundance was negatively correlated with disease index. [Conclusion] The antagonistic bacteria had a good control effect on tobacco wild fire. The composition and diversity of the microbial community in the tobacco leaves were significantly affected by the application of antagonistic bacteria. The dominant bacteria such as Pseudomonas and Stenotrophomonas could colonize in the tobacco leaves and play a role in controlling tobacco wild fire.

Key words:tobacco wild fire;antagonistic bacteria groups;phyllosphere microbial;community structure;diversity