Ralstonia solanacearum is an important soil-borne plant pathogen which causes bacterial wilt in a large number of crops. Bacterial Type Six Secretion System (T6SS) is known to participate in pathogenesis, bacterial interaction and inter-bacterial competition. Contribution of T6SS in the virulence of R. solanacearum on eggplant (Solanum melongena L) is studied. In this study, five T6SS gene (ompA, vgrG3, hcp, tssH and tssM) mutants have been developed by insertional mutagenesis and the virulence of the mutants was evaluated on eggplant. In general, the T6SS mutants showed significant reduction of wilt on eggplant. R. solanacearum mutant of ompA gene significantly reduced the wilt from day five through day eight in petiole inoculation. In soil drench inoculation, R. solanacearum mutant of vgrG3 gene reduced the wilt on eggplant and was significantly different throughout the experimental period. Other mutants, viz., tssH, tssM and hcp, also reduced the wilt during the initial stages of disease development. This is the first report on the role of T6SS genes, ompA, vgrG3, hcp and tssH on virulence of R. solanacearum.
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Type Six Secretion System
Ralstonia solanacearum Species complex
Type Two Secretion System
Type three Secretion system
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The financial support for this work was provided by Indian Council of Agricultural Research, New Delhi, India through “Outreach project on Phytophthora, Fusarium and Ralstonia diseases of horticultural and field crops”- (PhytoFuRa). The authors are grateful to Director, ICAR- Central Coastal Agricultural Research Institute, Old Goa for providing other necessary facilities.
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Asolkar, T., Ramesh, R. The involvement of the Type Six Secretion System (T6SS) in the virulence of Ralstonia solanacearum on brinjal. 3 Biotech 10, 324 (2020). https://doi.org/10.1007/s13205-020-02311-4
- Ralstonia solanacearum
- Bacterial wilt