Characterization of Ralstonia solanacearum Isolates, the Causal Agent of Brinjal Vascular Wilt by Flic Locus and Phage Typing

To characterize isolates of Ralstonia solanacearum race 3 (biovar II), the causal agent of brinjal vascular wilt, six isolates were used in the study, four isolates were characterized in terms of pathogenicity as virulent forms of R. solanacearum causing wilting symptoms. Phage typing by xRspv1 phage on five isolates resulted in lysis of three isolates viz., isolate S6 (clear and bigger plaques), isolate S3 (smaller and turbid) and isolate S5 (medium and clear plaques) with distinct plaque morphology. Molecular level confirmation was done using PCR technique with specific universal primers for R. solanacearum which revealed five isolates proved to be the species of R. solanacearum (∼280 bp), whereas, one isolate S2 was not belong to this category. fliC-virulence related gene located on the megaplasmid which was involved directly or indirectly in the disease process was also used to characterize the isolates by PCR resulted in five out of six isolates gave a distinct band of ∼400 bp except one (S2).