Pathogenicity of Ralstonia solanacearum isolated from tobacco in Guangdong, Fujian and Guizhou Province

Abstract:

[Objective] In order to isolate Ralstonia solanacearum from Guangdong, Fujian, Guizhou tobacco, determine its virulence and to explore ways to determine virulence. [Methods] Triphenyltetrazolium chloride culture medium and protein electrophoresis were used to distinguish the virulence of the bacteria. [Results] Fifty-nine R. solanacearum were isolated from bacterial wilt tobacco samples. We used SDS-PAGE to identify bacterial wilt virulence. The specific band in the SDS-PAGE was considered to be a certification for the virulence of R. solanacearum. The 59 strains were divided into 2 types according to their virulence. Five strains were non-virulent whereas 54 were virulent. All virulent strains were dominators in Guangdong, Fujian and Guizhou province. Among these regions, Guangdong has a slightly large proportion of virulence strains, followed by Fujian and Guizhou. Among of these strains, one strain belongs to type Ⅳ bacterial wilt, the other 58 belong to biotype Ⅲ or subtype biochemical Ⅲ-1. [Conclusion] Virulence of R. solanacearum has differentiated, and specific protein band in SDS-PAGE can be used as an evidence to judge whether the bacteria has virulence or not.

Key words:Tobacco, Ralstonia solanacearum, Protein electrophoresis, Biovar, Virulence