Genetic variability of Ralstonia solanacearum (E. F. Smith) Yabuuchi et al. isolated from soil planted to different solanaceous crops in the Philippines.

Ralstonia solanacearum (E. F. Smith) Yabuuchi et al. isolated from soil planted to different solanaceous crops were characterized based on traditional methods such as cultural characterization, and pathogenicity test. Isolates were collected from different areas in Luzon, specifically in Benguet and areas in Mindanao (Misamis Oriental and Bukidnon). Using the species-specific primers 759f/760r in multiplex-polymerase chain reaction, a 281-bp amplicon was generated from all the isolates which further confirm the identity of the bacterial isolates as R. solanacearum. Moreover, multiplex-PCR using phylotype-specific primers revealed that the Mindanao isolates belong to phylotype I while the Benguet isolates belong to phylotype II. Assessment of the genetic diversity of the R. solanacearum isolates by repetitive element (rep)PCR using REP and BOX primers showed the separation of the Mindanao isolates from the Benguet isolates based on geographic origin. These characterization studies are vital for analyzing the difference between the isolates affecting the solanaceous crops in the 'vegetable baskets' of Luzon and Mindanao which can be used for studies related to disease management, host resistance, and genetic relationships.